15.1: Why It Matters- Integration
Business needs drive collaboration, information sharing and business analysis. What that really means is that more ideas, data, and information needs to be used in combination to bring about better interpretation and understanding of those ideas, data, and information by people. The Microsoft suite of apps allows people to work together to move a business forward, communicate effectively, and become increasingly more successful.
You can also view a transcript for the video “Modern Applications: The People Story for Business” here (opens in new window) .
As this video mentions, the purpose of using these applications is to make business work easier between people. The purpose of this course is to give you the skills necessary to be more comfortable with the various tools and applications in order to do your job with ease.
At work, your to-do-list might include tasks such as ordering new products, completing purchase orders, creating sales charts, and producing proposals and presentations. This module will draw on the lessons you have learned in those previous modules and show you how to integrate various features from one application into another in order to finish these types of tasks.
Here is what you will be learning how to accomplish with this module:
- Create a Word document with integrated Excel utilizing skills from the previous modules
- Create a PowerPoint supporting presentation utilizing skills from the previous modules
- Integrate a video into a PowerPoint slide
- Integrate Excel and Access
Contributors and Attributions
- Why It Matters: Integration. Authored by : Sherri Pendleton. Provided by : Lumen Learning. License : CC BY: Attribution
- Modern Applications - The People Story for Business. Authored by : EPC Group.net. Located at : https://www.youtube.com/watch?v=N_ZlMNCl9UQ . License : CC BY: Attribution


10.12.4: Problems with Heterosexual Focus
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Sexism is discrimination based on sex . Heterosexism is the discrimination or prejudice based on not being heterosexual . In other words, heterosexism described the predominant thinking that there is an inherent superiority in being heterosexual, thereby limiting social acceptance, tolerance, and empathy for people who do not identify as being heterosexual. Sometimes this can come in the form of overt bigotry, but sometimes heterosexism can be harder to identify. For example, as a women, I cannot tell you how many times I’ve been asked if I have a boyfriend or husband. However, I can’t recall an instance where someone used more inclusive language to gain perspective into my relationship status. Something like, “Do you have a partner?” And I don’t think I’ve ever been asked if I have a girlfriend or wife.
Heterocentrism is the belief that heterosexuality is central and normal in contrast to other sexual orientations . This leads to other sexual orientations being viewed as inferior, abnormal, or even unacknowledged. Heterocentrism can be a fueling force behind homophobia, both at individual and societal levels. Homophobia is ideology that disadvantages sexual minority groups . Homophobia can take many forms: violence perpetrated against sexual minorities, failure to allow same-sex marriage, criminalizing homosexual behaviors (it wasn’t until 2003 the Supreme Court reversed the decision with Lawrence v. Texas, invalidating sodomy laws the criminalization of numerous sexual acts between people of the same sex), or discrimination in the workplace. However, homophobia is often overlooked (except in the occasional headline—events such as the brutal murders of Matthew Shepard, Brandon Teena, and Gwen Araujo). 92% of LGBTQ+ students report hearing homophobic slurs in school regularly, 84% of LGBTQ+ student report being threatened because of their sexual orientation, 39% of gay, lesbian, and bisexual students and 55% of transgender students reported having been shoved or pushed, and 64% percent of GLBTQ students reported feeling unsafe at school. 122
Where does much of the homophobia come from? Heterocentrism can lead to heterosexism, and of left unchecked, heterosexism will allow homophobia to flourish. Researcher, author, and professor of psychology at the University of Rochester explained:
“Individuals who identify as straight but in psychological tests show a strong attraction to the same sex may be threatened by gays and lesbians because homosexuals remind them of similar tendencies within themselves. In many cases these are people who are at war with themselves and they are turning this internal conflict outward. Sometimes people are threatened by gays and lesbians because they are fearing their own impulses, in a sense they ‘doth protest too much.’ In addition, it appears that sometimes those who would oppress others have been oppressed themselves, and we can have some compassion for them too, they may be unaccepting of others because they cannot be accepting of themselves.” 123
Reinforcing the focus on heterosexuality as being the normative or standard sexuality enhances anti- LBGT+ attitudes. Although those attitudes are declining in the United States, the minority still expressing these negative attitudes has a significant impact on LGBTQ+ people, their supporters, and society as a whole. Homonegativity and homophobia differ depending on the perpetrator or provocateur and the person on the receiving end of the negativity.
122
Advocates for Youth. 2016. How the Homophobic Climate in the United States Affects GLBTQ Youth.
http://www.advocatesforyouth.org/pub...ophobic-climat
e-in-the-unit ed-states-affects-glbtq-
youth
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Homophobia is More Pronounced in Individuals Who Have Internal Conflict Regarding Their Own Sexual Identity.
Journal of Personality and Social Psychology. April, 2012.


9.4: Types of Mutations
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- Ying Liu
- City College of San Francisco
Mutations (changes in a gene sequence) can result in mutant alleles that no longer produce the same level or type of active product as the wild-type allele. Any mutant allele can be classified into one of five types: (1) amorph, (2) hypomorph, (3) hypermorph, (4) neomorph, and (5) antimorph.
- Amorph alleles are complete loss-of-function. They make no active product – zero function. The absence of function can be due to a lack of transcription (gene regulation mutation) or due to the production of a malfunctioning (protein coding mutation) product. These are also sometimes referred to as a Null allele.
- Hypomorph alleles are only a partial loss-of-function. They make an incompletely functioning product. This could occur via reduced transcription or via the production of a product that lacks complete activity. These alleles are sometimes referred to as Leaky mutations, because they provide some function, but not complete function.
Both amorphs and hypomorphs tend to be recessive to wild type because the wild type allele is usually able to supply sufficient product to produce a wild type phenotype (called haplo-sufficient - see Chapter 6). If the mutant allele is not haplo-sufficient, then it will be dominant to the wild type.
While the first two classes involve a loss-of-function , the next two involve a gain-of-function – quantity or quality. Gain-of-function alleles are almost always dominant to the wild type allele.
- Hypermorph alleles produce more of the same, active product. This can occur via increased transcription or by changing the product to make it more efficient/effective at its function.
- Neomorph alleles produce an active product with a new, different function, something that the wild type allele doesn’t do. It can be either new expression (new tissue or time) or a mutation in the product to create a new function (additional substrate or new binding site), not present in the wild type product.
Antimorph alleles are relatively rare, and have an activity that is dominant and opposite to the wild-type function. These alleles usually have no normal function of their own and they interfere with the function from the wild type allele. Thus, when an antimorph allele is heterozygous with wild type, the wild type allele function is reduced. While at the molecular level there are many ways this can happen, the simplest model to explain antimorph effect is that the product acts as a dimer (or any multimer) and one mutant subunit poisons the whole complex. Antimorphs are also known as dominant negative mutations.
Identifying Muller’s Morphs - All mutations can be sorted into one of the five morphs base on how they behave when heterozygous with other alleles – deletion alleles (zero function), wild type alleles (normal function), and duplication alleles (double normal function).


3.3: Case Study - Badger Army Ammunition Plant
Badger Army Ammunition Plant (BAAP) Case Study
Case Study for Hazardous Waste
Environmental cleanup of the 7,400-acre Badger Army Ammunition Plant will be greater than $250 million. This is one of the 40 contaminated military sites in Wisconsin which the Defense Environmental Restoration Account cites as the most contaminated. In fact, 32 areas are polluted with dangerous levels of solvents, metals and explosive/incendiary waste. The water beneath the plant is contaminated with mutagenic chemicals that include carbon tetrachloride, trichloroethylene and dinitrotoluenes. One part of the site, known as the Propellant Burning Grounds, is the source of a three-mile plume of contaminated groundwater that has migrated offsite, completely contaminating private drinking water wells in addition to the Wisconsin River.
Elevated Cancer Rates
In 1990, the Wisconsin Division of Health conducted a health survey. It concluded that communities near the Badger plant have a significantly higher incidence of cancer and deaths. In spite of these alarming findings, the State refused to take any action. In 1995, the Division of Health responded because of pressure from CSWAB (Citizens for Safe Water Around Badger) and reopened the community health study.
On October 26, 1998, CSWAB concluded “there was entirely inadequate contact with our community – the population being studied.” Prior to September 1998, no press releases were published, no public meetings were held, and no interviews were conducted. Despite several requests, virtually no resources were devoted to interviewing residents about current health problems and concerns regarding their exposure to air, dust, emissions, and surface soils. Assessment of risk from cleanup activities was also absent. CSWAB also determined that the Wisconsin DOH focused on death studies when many health problems and community concerns have been nonlethal, such as respiratory illnesses or reproductive problems.
CSWAB appealed to ATSDR (Agency for Toxic Substances and Disease Registry in D.C.) to discuss the lack of adequate community participation in this and similar health assessments across the nation. The Wisconsin Department of Health conducted the assessment under a cooperative agreement with ATSDR.
Cleanup Plans Abandoned
The U.S. Army proposed to abandon and severely reduce cleanup of two priority areas within the plant. The Settling Ponds and Spoils Disposal area — a series of lagoons that run the length of the 7,000-acre facility — is contaminated with high levels of lead and dinitrotoluenes.
Maintenance of the Badger plant costs in excess of $17 million per year. In 1991, only $3 million was allocated for environmental studies. Since 1975, there have been over 56 chemical spills and incidents. Moreover, there is no national strategic need for maintaining the Badger plant. A February 20, 1997 Government Accounting Office report concludes BAAP and three other military plants could be eliminated “because alternative sources exist…to provide the capabilities these plants provide.”


8.3: The Cell Cycle
By the end of this section, you will be able to do the following:
- Describe the three stages of interphase
- Discuss the behavior of chromosomes during karyokinesis/mitosis
- Explain how the cytoplasmic content is divided during cytokinesis
- Define the quiescent G 0 phase
The cell cycle is an ordered series of events involving cell growth and cell division that produces two new daughter cells. Cells on the path to cell division proceed through a series of precisely timed and carefully regulated stages of growth, DNA replication, and nuclear and cytoplasmic division that ultimately produces two identical (clone) cells. The cell cycle has two major phases: interphase and the mitotic phase (Figure \(\PageIndex{1}\)). During interphase , the cell grows and DNA is replicated. During the mitotic phase , the replicated DNA and cytoplasmic contents are separated, and the cell cytoplasm is typically partitioned by a third process of the cell cycle called cytokinesis . We should note, however, that interphase and mitosis (karyokinesis) may take place without cytokinesis, in which case cells with multiple nuclei (multinucleate cells) are produced.
Interphase
During interphase, the cell undergoes normal growth processes while also preparing for cell division. In order for a cell to move from interphase into the mitotic phase, many internal and external conditions must be met. The three stages of interphase are called G 1 , S, and G 2 .
G 1 Phase (First Gap)
The first stage of interphase is called the G 1 phase (first gap) because, from a microscopic point of view, little change is visible. However, during the G 1 stage, the cell is quite active at the biochemical level. The cell is accumulating the building blocks of chromosomal DNA and the associated proteins as well as accumulating sufficient energy reserves to complete the task of replicating each chromosome in the nucleus.
S Phase (Synthesis of DNA)
Throughout interphase, nuclear DNA remains in a semi-condensed chromatin configuration. In the S phase , DNA replication can proceed through the mechanisms that result in the formation of identical pairs of DNA molecules—sister chromatids—that are firmly attached at the centromeric region. The centrosome is also duplicated during the S phase. The two centrosomes will give rise to the mitotic spindle , the apparatus that orchestrates the movement of chromosomes during mitosis. For example, roughly at the center of each animal cell, the centrosomes are associated with a pair of rod-like objects, the centrioles , which are positioned at right angles to each other. Centrioles help organize cell division. We should note, however, that centrioles are not present in the centrosomes of other eukaryotic organisms, such as plants and most fungi.
G 2 Phase (Second Gap)
In the G 2 phase , the cell replenishes its energy stores and synthesizes proteins necessary for chromosome manipulation and movement. Some cell organelles are duplicated, and the cytoskeleton is dismantled to provide resources for the mitotic phase. There may be additional cell growth during G 2 . The final preparations for the mitotic phase must be completed before the cell is able to enter the first stage of mitosis.
The Mitotic Phase
The mitotic phase is a multistep process during which the duplicated chromosomes are aligned, separated, and move into two new, identical daughter cells. The first portion of the mitotic phase is called karyokinesis , or nuclear division. As we have just seen, the second portion of the mitotic phase (and often viewed as a process separate from and following mitosis) is called cytokinesis—the physical separation of the cytoplasmic components into the two daughter cells.
Link to Learning
Link to Learning
Revisit the stages of mitosis at the University of Arizona Biology Project Mitosis Tutorial
Karyokinesis (Mitosis)
Karyokinesis, also known as mitosis , is divided into a series of phases—prophase, prometaphase, metaphase, anaphase, and telophase—that result in the division of the cell nucleus (Figure \(\PageIndex{2}\)).
Visual Connection
Visual Connection
Which of the following is the correct order of events in mitosis?
- Sister chromatids line up at the metaphase plate. The kinetochore becomes attached to the mitotic spindle. The nucleus reforms and the cell divides. Cohesin proteins break down and the sister chromatids separate.
- The kinetochore becomes attached to the mitotic spindle. Cohesin proteins break down and the sister chromatids separate. Sister chromatids line up at the metaphase plate. The nucleus reforms and the cell divides.
- The kinetochore becomes attached to the cohesin proteins. Sister chromatids line up at the metaphase plate. The kinetochore breaks down and the sister chromatids separate. The nucleus reforms and the cell divides.
- The kinetochore becomes attached to the mitotic spindle. Sister chromatids line up at the metaphase plate. Cohesin proteins break down and the sister chromatids separate. The nucleus reforms and the cell divides.
Prophase (the “first phase”): the nuclear envelope starts to dissociate into small vesicles, and the membranous organelles (such as the Golgi complex [Golgi apparatus] and the endoplasmic reticulum), fragment and disperse toward the periphery of the cell. The nucleolus disappears (disperses) as well, and the centrosomes begin to move to opposite poles of the cell. Microtubules that will form the mitotic spindle extend between the centrosomes, pushing them farther apart as the microtubule fibers lengthen. The sister chromatids begin to coil more tightly with the aid of condensin proteins and now become visible under a light microscope.
Prometaphase (the “first change phase”): Many processes that began in prophase continue to advance. The remnants of the nuclear envelope fragment further, and the mitotic spindle continues to develop as more microtubules assemble and stretch across the length of the former nuclear area. Chromosomes become even more condensed and discrete. Each sister chromatid develops a protein structure called a kinetochore in its centromeric region (Figure \(\PageIndex{3}\)). The proteins of the kinetochore attract and bind to the mitotic spindle microtubules. As the spindle microtubules extend from the centrosomes, some of these microtubules come into contact with and firmly bind to the kinetochores. Once a mitotic fiber attaches to a chromosome, the chromosome will be oriented until the kinetochores of sister chromatids face the opposite poles . Eventually, all the sister chromatids will be attached via their kinetochores to microtubules from opposing poles. Spindle microtubules that do not engage the chromosomes are called polar microtubules . These microtubules overlap each other midway between the two poles and contribute to cell elongation . Astral microtubules are located near the poles, aid in spindle orientation, and are required for the regulation of mitosis.
Metaphase (the “change phase”): All the chromosomes are aligned in a plane called the metaphase plate , or the equatorial plane, roughly midway between the two poles of the cell. The sister chromatids are still tightly attached to each other by cohesin proteins. At this time, the chromosomes are maximally condensed.
Anaphase (“upward phase”): The cohesin proteins degrade, and the sister chromatids separate at the centromere. Each chromatid, now called a single chromosome, is pulled rapidly toward the centrosome to which its microtubule is attached. The cell becomes visibly elongated (oval shaped) as the polar microtubules slide against each other at the metaphase plate where they overlap.
Telophase (the “distance phase”): the chromosomes reach the opposite poles and begin to decondense (unravel), relaxing once again into a stretched-out chromatin configuration. The mitotic spindles are depolymerized into tubulin monomers that will be used to assemble cytoskeletal components for each daughter cell. Nuclear envelopes form around the chromosomes, and nucleosomes appear within the nuclear area.
Cytokinesis
Cytokinesis , or “cell motion,” is sometimes viewed as the second main stage of the mitotic phase, during which cell division is completed via the physical separation of the cytoplasmic components into two daughter cells (Figure \(\PageIndex{4}\)) However, as we have seen earlier, cytokinesis can also be viewed as a separate phase, which may or may not take place following mitosis. If cytokinesis does take place, cell division is not complete until the cell components have been apportioned and completely separated into the two daughter cells. Although the stages of mitosis are similar for most eukaryotes, the process of cytokinesis is quite different for eukaryotes that have cell walls, such as plant cells.
In animal cells, cytokinesis typically starts during late anaphase. A contractile ring composed of actin filaments forms just inside the plasma membrane at the former metaphase plate. The actin filaments pull the equator of the cell inward, forming a fissure. This fissure is called the cleavage furrow . The furrow deepens as the actin ring contracts, and eventually the membrane is cleaved in two (Figure \(\PageIndex{5}\)).
In plant cells, a new cell wall must form between the daughter cells. During interphase, the Golgi apparatus accumulates enzymes, structural proteins, and glucose molecules prior to breaking into vesicles and dispersing throughout the dividing cell. During telophase, these Golgi vesicles are transported on microtubules to form a phragmoplast (a vesicular structure) at the metaphase plate. There, the vesicles fuse and coalesce from the center toward the cell walls; this structure is called a cell plate . As more vesicles fuse, the cell plate enlarges until it merges with the cell walls at the periphery of the cell. Enzymes use the glucose that has accumulated between the membrane layers to build a new cell wall. The Golgi membranes become parts of the plasma membrane on either side of the new cell wall (Figure \(\PageIndex{5}\)).
G 0 Phase
Not all cells adhere to the classic cell-cycle pattern in which a newly formed daughter cell immediately enters the preparatory phases of interphase, closely followed by the mitotic phase, and cytokinesis. Cells in G 0 phase are not actively preparing to divide. The cell is in a quiescent (inactive) stage that occurs when cells exit the cell cycle. Some cells enter G 0 temporarily due to environmental conditions such as availability of nutrients, or stimulation by growth factors. The cell will remain in this phase until conditions improve or until an external signal triggers the onset of G 1 . Other cells that never or rarely divide, such as mature cardiac muscle and nerve cells, remain in G 0 permanently.
Scientific Method Connection
Scientific Method Connection
Determine the Time Spent in Cell-Cycle Stages
Problem : How long does a cell spend in interphase compared to each stage of mitosis?
Background : A prepared microscope slide of whitefish blastula cross-sections will show cells arrested in various stages of the cell cycle. (Note: It is not visually possible to separate the stages of interphase from each other, but the mitotic stages are readily identifiable.) If 100 cells are examined, the number of cells in each identifiable cell-cycle stage will give an estimate of the time it takes for the cell to complete that stage.
Problem Statement : Given the events included in all of interphase and those that take place in each stage of mitosis, estimate the length of each stage based on a 24-hour cell cycle. Before proceeding, state your hypothesis.
Test your hypothesis : Test your hypothesis by doing the following:
- Place a fixed and stained microscope slide of whitefish blastula cross-sections under the scanning objective of a light microscope.
- Locate and focus on one of the sections using the low-power objective of your microscope. Notice that the section is a circle composed of dozens of closely packed individual cells.
- Switch to the medium-power objective and refocus. With this objective, individual cells are clearly visible, but the chromosomes will still be very small.
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Switch to the high-power objective and slowly move the slide left to right, and up and down to view all the cells in the section (Figure \(\PageIndex{6}\)). As you scan, you will notice that most of the cells are not undergoing mitosis but are in the interphase period of the cell cycle.
- Practice identifying the various stages of the cell cycle, using the drawings of the stages as a guide (Figure \(\PageIndex{2}\)).
- Once you are confident about your identification, begin to record the stage of each cell you encounter as you scan left to right, and top to bottom across the blastula section.
- Keep a tally of your observations and stop when you reach 100 cells identified.
- The larger the sample size (total number of cells counted), the more accurate the results. If possible, gather and record group data prior to calculating percentages and making estimates.
Record your observations : Make a table similar to Table \(\PageIndex{1}\) within which to record your observations.
| Phase or Stage | Individual Totals | Group Totals | Percent |
|---|---|---|---|
| Interphase | |||
| Prophase | |||
| Metaphase | |||
| Anaphase | |||
| Telophase | |||
| Cytokinesis | |||
| Totals | 100 | 100 | 100 percent |
Analyze your data/report your results : To find the length of time whitefish blastula cells spend in each stage, multiply the percent (recorded as a decimal) by 24 hours. Make a table similar to Table \(\PageIndex{2}\) to illustrate your data.
| Phase or Stage | Percent | Time in Hours |
|---|---|---|
| Interphase | ||
| Prophase | ||
| Metaphase | ||
| Anaphase | ||
| Telophase | ||
| Cytokinesis |
Draw a conclusion : Did your results support your estimated times? Were any of the outcomes unexpected? If so, discuss those events in that stage that may have contributed to the calculated time.
Contributors and Attributions
Remixed and/or curated from the following works:
Clark, M. A., Douglas, M., & Choi, J. (2018). 2.7.3 The Cell Cycle . In Biology 2e . OpenStax (CC BY 4.0; Access for free at https://openstax.org/books/biology-2e/pages/1-introduction ).


1.3: Line Spectra and the Bohr Model
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Learning Objectives
- To know the relationship between atomic spectra and the electronic structure of atoms.
The concept of the photon emerged from experimentation with thermal radiation , electromagnetic radiation emitted as the result of a source’s temperature, which produces a continuous spectrum of energies.The photoelectric effect provided indisputable evidence for the existence of the photon and thus the particle-like behavior of electromagnetic radiation. However, more direct evidence was needed to verify the quantized nature of energy in all matter. In this section, we describe how observation of the interaction of atoms with visible light provided this evidence.
Line Spectra
Although objects at high temperature emit a continuous spectrum of electromagnetic radiation, a different kind of spectrum is observed when pure samples of individual elements are heated. For example, when a high-voltage electrical discharge is passed through a sample of hydrogen gas at low pressure, the resulting individual isolated hydrogen atoms caused by the dissociation of H 2 emit a red light. Unlike blackbody radiation, the color of the light emitted by the hydrogen atoms does not depend greatly on the temperature of the gas in the tube. When the emitted light is passed through a prism, only a few narrow lines of particular wavelengths, called a line spectrum , are observed rather than a continuous range of wavelengths (Figure \(\PageIndex{1}\)). The light emitted by hydrogen atoms is red because, of its four characteristic lines, the most intense line in its spectrum is in the red portion of the visible spectrum, at 656 nm. With sodium, however, we observe a yellow color because the most intense lines in its spectrum are in the yellow portion of the spectrum, at about 589 nm.
Such emission spectra were observed for many other elements in the late 19th century, which presented a major challenge because classical physics was unable to explain them. Part of the explanation is provided by Planck’s equation: the observation of only a few values of λ (or \( u \)) in the line spectrum meant that only a few values of E were possible. Thus the energy levels of a hydrogen atom had to be quantized ; in other words, only states that had certain values of energy were possible, or allowed . If a hydrogen atom could have any value of energy, then a continuous spectrum would have been observed, similar to blackbody radiation.
In 1885, a Swiss mathematics teacher, Johann Balmer (1825–1898), showed that the frequencies of the lines observed in the visible region of the spectrum of hydrogen fit a simple equation that can be expressed as follows:
\[ u=constant\; \left ( \dfrac{1}{2^{2}}-\dfrac{1}{n^{^{2}}} \right ) \label{6.3.1} \]
where n = 3, 4, 5, 6. As a result, these lines are known as the Balmer series . The Swedish physicist Johannes Rydberg (1854–1919) subsequently restated and expanded Balmer’s result in the Rydberg equation :
\[ \dfrac{1}{\lambda }=\Re\; \left ( \dfrac{1}{n^{2}_{1}}-\dfrac{1}{n^{2}_{2}} \right ) \label{6.3.2} \]
where \(n_1\) and \(n_2\) are positive integers, \(n_2 > n_1\), and \( \Re \) the Rydberg constant , has a value of 1.09737 × 10 7 m −1 .
Johann Balmer (1825–1898)
A mathematics teacher at a secondary school for girls in Switzerland, Balmer was 60 years old when he wrote the paper on the spectral lines of hydrogen that made him famous.
Balmer published only one other paper on the topic, which appeared when he was 72 years old.
Like Balmer’s equation, Rydberg’s simple equation described the wavelengths of the visible lines in the emission spectrum of hydrogen (with n 1 = 2, n 2 = 3, 4, 5,…). More important, Rydberg’s equation also predicted the wavelengths of other series of lines that would be observed in the emission spectrum of hydrogen: one in the ultraviolet ( n 1 = 1, n 2 = 2, 3, 4,…) and one in the infrared ( n 1 = 3, n 2 = 4, 5, 6). Unfortunately, scientists had not yet developed any theoretical justification for an equation of this form.
Bohr's Model
In 1913, a Danish physicist, Niels Bohr (1885–1962; Nobel Prize in Physics, 1922), proposed a theoretical model for the hydrogen atom that explained its emission spectrum. Bohr’s model required only one assumption: The electron moves around the nucleus in circular orbits that can have only certain allowed radii. Rutherford’s earlier model of the atom had also assumed that electrons moved in circular orbits around the nucleus and that the atom was held together by the electrostatic attraction between the positively charged nucleus and the negatively charged electron. Although we now know that the assumption of circular orbits was incorrect, Bohr’s insight was to propose that the electron could occupy only certain regions of space .
Using classical physics, Niels Bohr showed that the energy of an electron in a particular orbit is given by
\[ E_{n}=\dfrac{-\Re hc}{n^{2}} \label{6.3.3} \]
where \( \Re \) is the Rydberg constant, h is Planck’s constant, c is the speed of light, and n is a positive integer corresponding to the number assigned to the orbit, with n = 1 corresponding to the orbit closest to the nucleus. In this model n = ∞ corresponds to the level where the energy holding the electron and the nucleus together is zero. In that level, the electron is unbound from the nucleus and the atom has been separated into a negatively charged (the electron) and a positively charged (the nucleus) ion. In this state the radius of the orbit is also infinite. The atom has been ionized.
Niels Bohr (1885–1962)
During the Nazi occupation of Denmark in World War II , Bohr escaped to the United States, where he became associated with the Atomic Energy Project.
In his final years, he devoted himself to the peaceful application of atomic physics and to resolving political problems arising from the development of atomic weapons.
As n decreases, the energy holding the electron and the nucleus together becomes increasingly negative, the radius of the orbit shrinks and more energy is needed to ionize the atom. The orbit with n = 1 is the lowest lying and most tightly bound. The negative sign in Equation \(\ref{6.3.3}\) indicates that the electron-nucleus pair is more tightly bound (i.e. at a lower potential energy) when they are near each other than when they are far apart. Because a hydrogen atom with its one electron in this orbit has the lowest possible energy, this is the ground state (the most stable arrangement of electrons for an element or a compound) for a hydrogen atom. As n increases, the radius of the orbit increases; the electron is farther from the proton, which results in a less stable arrangement with higher potential energy (Figure \(\PageIndex{2a}\)). A hydrogen atom with an electron in an orbit with n > 1 is therefore in an excited state , defined as any arrangement of electrons that is higher in energy than the ground state. When an atom in an excited state undergoes a transition to the ground state in a process called decay, it loses energy by emitting a photon whose energy corresponds to the difference in energy between the two states (Figure \(\PageIndex{1}\)).
So the difference in energy (\(ΔE\)) between any two orbits or energy levels is given by \( \Delta E=E_{n_{1}}-E_{n_{2}} \) where n 1 is the final orbit and n 2 the initial orbit. Substituting from Bohr’s equation (Equation \ref{6.3.3}) for each energy value gives
\[\begin{align*} \Delta E &=E_{final}-E_{initial} \\[4pt] &=-\dfrac{\Re hc}{n_{2}^{2}}-\left ( -\dfrac{\Re hc}{n_{1}^{2}} \right ) \\[4pt] &=-\Re hc\left ( \dfrac{1}{n_{2}^{2}} - \dfrac{1}{n_{1}^{2}}\right ) \label{6.3.4} \end{align*} \]
If \(n_2 > n_1\), the transition is from a higher energy state (larger-radius orbit) to a lower energy state (smaller-radius orbit), as shown by the dashed arrow in part (a) in Figure \(\PageIndex{3}\). Substituting \(hc/λ\) for \(ΔE\) gives
\[ \Delta E = \dfrac{hc}{\lambda }=-\Re hc\left ( \dfrac{1}{n_{2}^{2}} - \dfrac{1}{n_{1}^{2}}\right ) \label{6.3.5} \]
Canceling \(hc\) on both sides gives
\[ \dfrac{1}{\lambda }=-\Re \left ( \dfrac{1}{n_{2}^{2}} - \dfrac{1}{n_{1}^{2}}\right ) \label{6.3.6} \]
Except for the negative sign, this is the same equation that Rydberg obtained experimentally. The negative sign in Equations \(\ref{6.3.5}\) and \(\ref{6.3.6}\) indicates that energy is released as the electron moves from orbit \(n_2\) to orbit \(n_1\) because orbit \(n_2\) is at a higher energy than orbit \(n_1\). Bohr calculated the value of \(\Re\) from fundamental constants such as the charge and mass of the electron and Planck's constant and obtained a value of 1.0974 × 10 7 m −1 , the same number Rydberg had obtained by analyzing the emission spectra.
We can now understand the physical basis for the Balmer series of lines in the emission spectrum of hydrogen (\(\PageIndex{3b}\)); the lines in this series correspond to transitions from higher-energy orbits (n > 2) to the second orbit (n = 2). Thus the hydrogen atoms in the sample have absorbed energy from the electrical discharge and decayed from a higher-energy excited state (n > 2) to a lower-energy state (n = 2) by emitting a photon of electromagnetic radiation whose energy corresponds exactly to the difference in energy between the two states (Figure \(\PageIndex{3a}\)). The n = 3 to n = 2 transition gives rise to the line at 656 nm (red), the n = 4 to n = 2 transition to the line at 486 nm (green), the n = 5 to n = 2 transition to the line at 434 nm (blue), and the n = 6 to n = 2 transition to the line at 410 nm (violet). Because a sample of hydrogen contains a large number of atoms, the intensity of the various lines in a line spectrum depends on the number of atoms in each excited state. At the temperature in the gas discharge tube, more atoms are in the n = 3 than the n ≥ 4 levels. Consequently, the n = 3 to n = 2 transition is the most intense line, producing the characteristic red color of a hydrogen discharge (Figure \(\PageIndex{1a}\)). Other families of lines are produced by transitions from excited states with n > 1 to the orbit with n = 1 or to orbits with n ≥ 3. These transitions are shown schematically in Figure \(\PageIndex{4}\)
The Bohr Atom: The Bohr Atom, YouTube(opens in new window) [youtu.be]
Using Atoms to Time
In contemporary applications, electron transitions are used in timekeeping that needs to be exact. Telecommunications systems, such as cell phones, depend on timing signals that are accurate to within a millionth of a second per day, as are the devices that control the US power grid. Global positioning system (GPS) signals must be accurate to within a billionth of a second per day, which is equivalent to gaining or losing no more than one second in 1,400,000 years. Quantifying time requires finding an event with an interval that repeats on a regular basis.
To achieve the accuracy required for modern purposes, physicists have turned to the atom. The current standard used to calibrate clocks is the cesium atom. Supercooled cesium atoms are placed in a vacuum chamber and bombarded with microwaves whose frequencies are carefully controlled. When the frequency is exactly right, the atoms absorb enough energy to undergo an electronic transition to a higher-energy state. Decay to a lower-energy state emits radiation. The microwave frequency is continually adjusted, serving as the clock’s pendulum.
In 1967, the second was defined as the duration of 9,192,631,770 oscillations of the resonant frequency of a cesium atom, called the cesium clock . Research is currently under way to develop the next generation of atomic clocks that promise to be even more accurate. Such devices would allow scientists to monitor vanishingly faint electromagnetic signals produced by nerve pathways in the brain and geologists to measure variations in gravitational fields, which cause fluctuations in time, that would aid in the discovery of oil or minerals.
Example \(\PageIndex{1}\): The Lyman Series
The so-called Lyman series of lines in the emission spectrum of hydrogen corresponds to transitions from various excited states to the n = 1 orbit. Calculate the wavelength of the lowest-energy line in the Lyman series to three significant figures. In what region of the electromagnetic spectrum does it occur?
Given: lowest-energy orbit in the Lyman series
Asked for: wavelength of the lowest-energy Lyman line and corresponding region of the spectrum
Strategy:
- Substitute the appropriate values into Equation \ref{6.3.2} (the Rydberg equation) and solve for \(\lambda\).
- Use Figure 2.2.1 to locate the region of the electromagnetic spectrum corresponding to the calculated wavelength.
Solution:
We can use the Rydberg equation to calculate the wavelength:
\[ \dfrac{1}{\lambda }=-\Re \left ( \dfrac{1}{n_{2}^{2}} - \dfrac{1}{n_{1}^{2}}\right ) \nonumber \]
A For the Lyman series, n 1 = 1. The lowest-energy line is due to a transition from the n = 2 to n = 1 orbit because they are the closest in energy.
\[ \dfrac{1}{\lambda }=-\Re \left ( \dfrac{1}{n_{2}^{2}} - \dfrac{1}{n_{1}^{2}}\right )=1.097\times m^{-1}\left ( \dfrac{1}{1}-\dfrac{1}{4} \right )=8.228 \times 10^{6}\; m^{-1} \nonumber \]
It turns out that spectroscopists (the people who study spectroscopy) use cm -1 rather than m -1 as a common unit. Wavelength is inversely proportional to energy but frequency is directly proportional as shown by Planck's formula, \(E=h u\).
Spectroscopists often talk about energy and frequency as equivalent. The cm -1 unit is particularly convenient. The infrared range is roughly 200 - 5,000 cm -1 , the visible from 11,000 to 25.000 cm -1 and the UV between 25,000 and 100,000 cm -1 . The units of cm -1 are called wavenumbers, although people often verbalize it as inverse centimeters. We can convert the answer in part A to cm -1 .
\[ \widetilde{ u} =\dfrac{1}{\lambda }=8.228\times 10^{6}\cancel{m^{-1}}\left (\dfrac{\cancel{m}}{100\;cm} \right )=82,280\: cm^{-1} \nonumber \]
and
\[\lambda = 1.215 \times 10^{−7}\; m = 122\; nm \nonumber \]
This emission line is called Lyman alpha. It is the strongest atomic emission line from the sun and drives the chemistry of the upper atmosphere of all the planets, producing ions by stripping electrons from atoms and molecules. It is completely absorbed by oxygen in the upper stratosphere, dissociating O 2 molecules to O atoms which react with other O 2 molecules to form stratospheric ozone.
B This wavelength is in the ultraviolet region of the spectrum.
Exercise \(\PageIndex{1}\): The Pfund Series
The Pfund series of lines in the emission spectrum of hydrogen corresponds to transitions from higher excited states to the n = 5 orbit. Calculate the wavelength of the second line in the Pfund series to three significant figures. In which region of the spectrum does it lie?
- Answer
-
4.65 × 10 3 nm; infrared
Bohr’s model of the hydrogen atom gave an exact explanation for its observed emission spectrum. The following are his key contributions to our understanding of atomic structure:
Unfortunately, Bohr could not explain why the electron should be restricted to particular orbits. Also, despite a great deal of tinkering, such as assuming that orbits could be ellipses rather than circles, his model could not quantitatively explain the emission spectra of any element other than hydrogen (Figure \(\PageIndex{5}\)). In fact, Bohr’s model worked only for species that contained just one electron: H, He + , Li 2 + , and so forth. Scientists needed a fundamental change in their way of thinking about the electronic structure of atoms to advance beyond the Bohr model.
The Energy States of the Hydrogen Atom
Thus far we have explicitly considered only the emission of light by atoms in excited states, which produces an emission spectrum (a spectrum produced by the emission of light by atoms in excited states). The converse, absorption of light by ground-state atoms to produce an excited state, can also occur, producing an absorption spectrum (a spectrum produced by the absorption of light by ground-state atoms).
When an atom emits light, it decays to a lower energy state; when an atom absorbs light, it is excited to a higher energy state.
If white light is passed through a sample of hydrogen, hydrogen atoms absorb energy as an electron is excited to higher energy levels (orbits with n ≥ 2). If the light that emerges is passed through a prism, it forms a continuous spectrum with black lines (corresponding to no light passing through the sample) at 656, 468, 434, and 410 nm. These wavelengths correspond to the n = 2 to n = 3, n = 2 to n = 4, n = 2 to n = 5, and n = 2 to n = 6 transitions. Any given element therefore has both a characteristic emission spectrum and a characteristic absorption spectrum, which are essentially complementary images.
Emission and absorption spectra form the basis of spectroscopy , which uses spectra to provide information about the structure and the composition of a substance or an object. In particular, astronomers use emission and absorption spectra to determine the composition of stars and interstellar matter. As an example, consider the spectrum of sunlight shown in Figure \(\PageIndex{7}\) Because the sun is very hot, the light it emits is in the form of a continuous emission spectrum. Superimposed on it, however, is a series of dark lines due primarily to the absorption of specific frequencies of light by cooler atoms in the outer atmosphere of the sun. By comparing these lines with the spectra of elements measured on Earth, we now know that the sun contains large amounts of hydrogen, iron, and carbon, along with smaller amounts of other elements. During the solar eclipse of 1868, the French astronomer Pierre Janssen (1824–1907) observed a set of lines that did not match those of any known element. He suggested that they were due to the presence of a new element, which he named helium , from the Greek helios , meaning “sun.” Helium was finally discovered in uranium ores on Earth in 1895. Alpha particles are helium nuclei. Alpha particles emitted by the radioactive uranium pick up electrons from the rocks to form helium atoms.
The familiar red color of neon signs used in advertising is due to the emission spectrum of neon shown in part (b) in Figure \(\PageIndex{5}\). Similarly, the blue and yellow colors of certain street lights are caused, respectively, by mercury and sodium discharges. In all these cases, an electrical discharge excites neutral atoms to a higher energy state, and light is emitted when the atoms decay to the ground state. In the case of mercury, most of the emission lines are below 450 nm, which produces a blue light (part (c) in Figure \(\PageIndex{5}\)). In the case of sodium, the most intense emission lines are at 589 nm, which produces an intense yellow light.
Summary
There is an intimate connection between the atomic structure of an atom and its spectral characteristics. Atoms of individual elements emit light at only specific wavelengths, producing a line spectrum rather than the continuous spectrum of all wavelengths produced by a hot object. Niels Bohr explained the line spectrum of the hydrogen atom by assuming that the electron moved in circular orbits and that orbits with only certain radii were allowed. Lines in the spectrum were due to transitions in which an electron moved from a higher-energy orbit with a larger radius to a lower-energy orbit with smaller radius. The orbit closest to the nucleus represented the ground state of the atom and was most stable; orbits farther away were higher-energy excited states . Transitions from an excited state to a lower-energy state resulted in the emission of light with only a limited number of wavelengths. Atoms can also absorb light of certain energies, resulting in a transition from the ground state or a lower-energy excited state to a higher-energy excited state. This produces an absorption spectrum , which has dark lines in the same position as the bright lines in the emission spectrum of an element. Bohr’s model revolutionized the understanding of the atom but could not explain the spectra of atoms heavier than hydrogen.
Key Concepts
- Electrons can occupy only certain regions of space, called orbits .
- Orbits closer to the nucleus are lower in energy.
- Electrons can move from one orbit to another by absorbing or emitting energy, giving rise to characteristic spectra.


1.2.2: Entrepreneurship Today
Why Do People Become Entrepreneurs, and What Are the Different Types of Entrepreneurs?
Brothers Fernando and Santiago Aguerre exhibited entrepreneurial tendencies at an early age. At 8 and 9 years old respectively, they sold strawberries and radishes from a vacant lot near their parents’ home in Plata del Mar on the Atlantic coast of Argentina. At 11 and 12, they provided a surfboard repair service from their garage. As teenagers, Fer and Santi, as they call each other, opened Argentina’s first surf shop, which led to their most ambitious entrepreneurial venture of all.
The flat-footed brothers found that traipsing across hot sand in flip-flops was uncomfortable, so in 1984 they sank their $4,000 savings into manufacturing their own line of beach sandals. Now offering sandals and footwear for women, men, and children, as well as clothing for men, Reef sandals have become the world’s hottest beach footwear, with a presence in nearly every surf shop in the United States.
Table \(\PageIndex{1}\): The Economic Impact of Small Business
| Most U.S. Businesses Are Small: |
|---|
|
CATCHING THE ENTREPRENEURIAL SPIRIT
Young Entrepreneur Living the Dream
Jack Bonneau is the quintessential entrepreneur. In the three years he has been in business, he has expanded his product line, opened multiple locations, established strategic partnerships, and secured sponsorship from several national brands. His business has garnered publicity from The New York Times, The Denver Post, The Today Show , Good Morning America , and numerous other media. He has shared his business success on several stages, speaking at TechStars and the Aspen Ideas Festival, and recently delivered the closing keynote speech at a national STEM conference. He even landed a gig on Shark Tank .
Jack Bonneau is smart, charismatic, an excellent spokesperson, and persistent in his mission. And he is only 11 years old—which also makes him very adorable.
Jack’s business was born from a need that most kids have: a desire for toys. He asked his dad, Steve Bonneau, for a LEGO Star Wars Death Star. The problem was that it cost $400. Jack’s dad said he could have it but only if he paid for it himself. This led Jack to do what a lot of kids do to earn some extra cash. He opened a lemonade stand. But he quickly learned that this would never help him realize his dream, so, with the advice and help of his father, he decided to open a lemonade stand at a local farmers market. “There were lots of people who wanted to buy great lemonade from an eight-year-old,” says Jack. In no time, Jack had earned enough to buy his LEGO Death Star. “I had sales of around $2,000, and my total profit was $900,” Jack said.
Jack realized that he was on to something. Adults love to buy things from cute kids. What if he could make even more money by opening more locations? Jack developed an expansion plan to open three new “Jack Stands” the following spring. Realizing that he would need more working capital, he secured a $5,000 loan from Young Americas Bank, a bank in Denver that specializes in loans to children. Jack made $25,000 in 2015.
The following year, Jack wanted to expand operations, so he secured a second loan for $12,000. He opened stands in several more locations, including shopping malls during the holiday season, selling apple cider and hot chocolate instead of lemonade. He also added additional shop space and recruited other young entrepreneurial kids to sell their products in his space, changing the name to Jack’s Stands and Marketplace. One of his first partnerships was Sweet Bee Sisters, a lip balm and lotion company founded by Lily, Chloe, and Sophie Warren. He also worked with 18 other young entrepreneurs who sell a range of products from organic dog treats to scarves and headbands.
Jack’s strategy worked, and the business brought in more than $100,000 last year. This year, he became the spokesperson for Santa Cruz Organic Lemonade, and he’s now looking at expanding into other cities such as Detroit and New Orleans.
Even though Jack is only 11 years old, he has already mastered financial literacy, customer service, marketing and sales, social skills, and other sound business practices—all the qualities of a successful entrepreneur.
Critical Thinking Questions
- What do you think enabled Jack Bonneau to start and grow a successful business at such a young age?
- What personal characteristics and values will Jack need to continue running his business while also attending school full-time?
Christy Glass Lowe, who monitors surf apparel for USBX Advisory Services LLC, notes, “They [Reef] built a brand from nothing and now they’re the dominant market share leader.”
The Aguerres, who currently live two blocks from each other in La Jolla, California, sold Reef to VF Corporation for more than $100 million in 2005. In selling Reef, “We’ve finally found our freedom,” Fernando says. “We traded money for time,” adds Santiago. Fernando remains active with surfing organizations, serving as president of the International Surfing Association, where he became known as “Ambassador of the Wave” for his efforts in getting all 90 worldwide members of the International Olympic Committee to unanimously vote in favor of including surfing in the 2020 Olympic Games. He has also been named “Waterman of the Year” by the Surf Industry Manufacturers Association two times in 24 years. Santi raises funds for his favorite not-for-profit, SurfAid. Both brothers are enjoying serving an industry that has served them so well.
The United States is blessed with a wealth of entrepreneurs such as the Aguerres who want to start a small business . According to research by the Small Business Administration, two-thirds of college students intend to be entrepreneurs at some point in their careers, aspiring to become the next Bill Gates or Jeff Bezos, founder of Amazon.com. But before you put out any money or expend energy and time, you’d be wise to check out Table <IP_ADDRESS> for some preliminary advice.
The desire to be one’s own boss cuts across all age, gender, and ethnic lines. Results of a recent U.S. Census Bureau survey of business owners show that minority groups and women are becoming business owners at a much higher rate than the national average. Table <IP_ADDRESS> illustrates these minority-owned business demographics.
Why has entrepreneurship remained such a strong part of the foundation of the U.S. business system for so many years? Because today’s global economy rewards innovative, flexible companies that can respond quickly to changes in the business environment. Such companies are started by entrepreneurs , people with vision, drive, and creativity, who are willing to take the risk of starting and managing a business to make a profit.
Table \(\PageIndex{2}\)
| Are You Ready to Be an Entrepreneur? |
|---|
Here are some questions would-be entrepreneurs should ask themselves:
|
Table \(\PageIndex{3}\)
| Statistics for Minority-Owned Businesses |
|---|
|
Entrepreneur or Small-Business Owner?
The term entrepreneur is often used in a broad sense to include most small-business owners. The two groups share some of the same characteristics, and we’ll see that some of the reasons for becoming an entrepreneur or a small-business owner are very similar. But there is a difference between entrepreneurship and small-business management. Entrepreneurship involves taking a risk, either to create a new business or to greatly change the scope and direction of an existing one. Entrepreneurs typically are innovators who start companies to pursue their ideas for a new product or service. They are visionaries who spot trends.
Although entrepreneurs may be small-business owners, not all small-business owners are entrepreneurs. Small-business owners are managers or people with technical expertise who started a business or bought an existing business and made a conscious decision to stay small. For example, the proprietor of your local independent bookstore is a small-business owner. Jeff Bezos, founder of Amazon.com, also sells books. But Bezos is an entrepreneur: He developed a new model—web-based book retailing—that revolutionized the bookselling world and then moved on to change retailing in general. Entrepreneurs are less likely to accept the status quo, and they generally take a longer-term view than the small-business owner.
Types of Entrepreneurs
Entrepreneurs fall into several categories: classic entrepreneurs, multipreneurs, and intrapreneurs.
Classic Entrepreneurs
Classic entrepreneurs are risk-takers who start their own companies based on innovative ideas. Some classic entrepreneurs are micropreneurs who start small and plan to stay small. They often start businesses just for personal satisfaction and the lifestyle. Miho Inagi is a good example of a micropreneur. On a visit to New York with college friends in 1998, Inagi fell in love with the city’s bagels. “I just didn’t think anything like a bagel could taste so good,” she said. Her passion for bagels led the young office assistant to quit her job and pursue her dream of one day opening her own bagel shop in Tokyo. Although her parents tried to talk her out of it, and bagels were virtually unknown in Japan, nothing deterred her. Other trips to New York followed, including an unpaid six-month apprenticeship at Ess-a-Bagel, where Inagi took orders, cleared trays, and swept floors. On weekends, owner Florence Wilpon let her make dough.
In August 2004, using $20,000 of her own savings and a $30,000 loan from her parents, Inagi finally opened tiny Maruichi Bagel. The timing was fortuitous, as Japan was about to experience a bagel boom. After a slow start, a favorable review on a local bagel website brought customers flocking for what are considered the best bagels in Tokyo. Inagi earns only about $2,300 a month after expenses, the same amount she was making as a company employee. “Before I opened this store I had no goals,” she says, “but now I feel so satisfied.”
In contrast, growth-oriented entrepreneurs want their business to grow into a major corporation. Most high-tech companies are formed by growth-oriented entrepreneurs. Jeff Bezos recognized that with Internet technology he could compete with large chains of traditional book retailers. Bezos’s goal was to build his company into a high-growth enterprise—and he chose a name that reflected his strategy: Amazon.com. Once his company succeeded in the book sector, Bezos applied his online retailing model to other product lines, from toys and house and garden items to tools, apparel, music, and services. In partnership with other retailers, Bezos is well on his way to making Amazon’s vision “to be Earth’s most customer-centric company; to build a place where people can come to find and discover anything they might want to buy online.”—a reality.
Multipreneurs
Then there are multipreneurs, entrepreneurs who start a series of companies. They thrive on the challenge of building a business and watching it grow. In fact, over half of the chief executives at Inc. 500 companies say they would start another company if they sold their current one. Brothers Jeff and Rich Sloan are a good example of multipreneurs, having turned numerous improbable ideas into successful companies. Over the past 20-plus years, they have renovated houses, owned a horse breeding and marketing business, invented a device to prevent car batteries from dying, and so on. Their latest venture, a multimedia company called StartupNation, helps individuals realize their entrepreneurial dreams. And the brothers know what company they want to start next: yours.
Intrapreneurs
Some entrepreneurs don’t own their own companies but apply their creativity, vision, and risk-taking within a large corporation. Called intrapreneurs , these employees enjoy the freedom to nurture their ideas and develop new products, while their employers provide regular salaries and financial backing. Intrapreneurs have a high degree of autonomy to run their own mini-companies within the larger enterprise. They share many of the same personality traits as classic entrepreneurs, but they take less personal risk. According to Gifford Pinchot, who coined the term intrapreneur in his book of the same name, large companies provide seed funds that finance in-house entrepreneurial efforts. These include Intel, IBM, Texas Instruments (a pioneering intrapreneurial company), Salesforce.com, and Xerox.
Why Become an Entrepreneur?
As the examples in this chapter show, entrepreneurs are found in all industries and have different motives for starting companies. The most common reason cited by CEOs of the Inc. 500, the magazine’s annual list of fastest-growing private companies, is the challenge of building a business, followed by the desire to control their own destiny. Other reasons include financial independence and the frustration of working for someone else. Two important motives mentioned in other surveys are a feeling of personal satisfaction with their work, and creating the lifestyle that they want. Do entrepreneurs feel that going into business for themselves was worth it? The answer is a resounding yes. Most say they would do it again.
CONCEPT CHECK
- Describe several types of entrepreneurs.
- What differentiates an entrepreneur from a small-business owner?
- What are some major factors that motivate entrepreneurs to start businesses?


5.5: Chapter 5 Summary
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Identify your life roles.
Prioritize tasks in each of your life roles.
Realize we cannot accomplish everything all at once.
Use Steven Covey’s Quadrant II Time Management System to organize demands on your time into the following quadrants:
Important and Urgent (I)
Important and Not Urgent (II)
Not Important and Urgent (III)
Not Important and Not Urgent (IV)
Use self-management tools to spend most of your time in Quadrant II. Examples include:
to-do list
weekly planner
monthly calendar
semester calendar/term schedule
smartphone apps
Realize we cannot manage time; we can manage only ourselves and how we use the time we’re given.
Communicate our priorities to important people in our lives.
Avoid procrastination by using the SMART strategies of “start small, manage your expectations, ask for help, reorder and time trick.”


12.8: Hamilton Paths
- Describe and identify Hamilton paths.
- Evaluate Hamilton paths in real-world applications.
- Distinguish between Hamilton paths and Euler trails.
In the United States, school buses carry 25 million children between school and home every day. The total distance they travel is around 6 billion kilometers per year. In the city of Boston, Massachusetts, the 2016 budget for running those buses was $120 million dollars. In 2017, the city held a competition to find ways to cut costs and the Quantum Team from the MIT Operations Research Center came to the rescue, using a computer algorithm to identify the most efficient and least costly routes, which saved the city of Boston $5 million each year and even reduced daily CO 2 emissions by 9,000 kilograms! ( This U.S. city put an algorithm in charge of its school bus routes and saved $5 million , Sean Fleming, World Economic Forum)
The problem the Quantum Team tackled involves graph theory.  The bus must start at the depot, visit every stop exactly once, and end at the school. The route is a special kind of path that visits every vertex exactly once. Can you guess what those paths are called?
Hamilton Paths
Just as circuits that visit each vertex in a graph exactly once are called Hamilton cycles (or Hamilton circuits), paths that visit each vertex on a graph exactly once are called Hamilton paths . As we explore Hamilton paths, you might find it helpful to refresh your memory about the relationships between walks, trails, and paths by looking at Figure . We know that paths are walks that don’t repeat any vertices or edges. So, a Hamilton path visits every vertex without repeating any vertices or edges. Figure shows a path from vertex A to vertex E and a Hamilton path from vertex A to vertex E .
Which of the following sequences of vertices is a Hamilton path for Graph Q in Figure
Figure ?- a → d → b → c → e → g → f
- c → b → e → h → g → f → d → a
- h → e → g → d → b → e → g → f → d → a → b → c
- Answer
-
Sequence 1 is a path, because it is a walk that doesn’t repeat any vertices or edges, but not a Hamilton path because it skips vertex h . Sequence 2 is a path that visits each vertex exactly once; so, it is a Hamilton path. Sequence 3 is a walk, but it is not a path because it visits vertices g , e , and b each more than once; so, it cannot be a Hamilton path. So, we can see that only sequence 2 is a Hamilton path.
Use the graphs to determine if the given sequence of vertices represents a Hamilton path or not.
Graph A , b → c → d → e → f
Graph A , b → e → f → c → b → d
Graph
K
,
n
→
q
→
o
→
p
→
m
TIP! Since a Hamilton path visits each vertex exactly once, it must have the same number of vertices listed as appear in the graph.
Finding Hamilton Paths
Suppose you were visiting an aquarium with some friends. The map of the aquarium is given in Figure 12.195. The letters represent the exhibits.
Figure
shows a graph of the aquarium in which each vertex represents an exhibit and each edge is a route between the pair of exhibits that doesn’t bypass another exhibit.Let’s see if we can plan a tour of the exhibits that visits each exhibit exactly once, beginning at exhibit O and ending at exhibit C . Suppose that, after exhibit O , we plan to visit exhibit Q and then exhibit M . After M , should we plan to visit N , L , or R ? Take a look at Figure
. If R is not chosen next, that will cause a problem later on. Do you see what it is?If L or N is chosen next, the only way to get to R later will be to go from S to R , and then we will not be able to continue without repeating a vertex. So, we will pick R next, and then the only option is S . After S we have another choice to make. As shown in Figure
, the next choice is between B and E . Keeping in mind that the goal is to end at C , which would be the better choice?If you said vertex B , you are right! Otherwise, we will not be able to visit B later. After B , the only option is E . Then we can choose either D or G . Either will work fine. Let’s choose G as shown in Figure
. After G , you must visit H , but should you visit K or L after that?If you said to go to vertex L next, you are right! Otherwise, it will be impossible to visit N without repeating a vertex. So, next is L , then N , then K , and then at J you have another decision to make we can see in Figure
.  If you choose either of the other two vertices, you will not be able to visit P later without passing through another vertex twice. Once P is chosen, vertex I must be next followed by F . Then you have to choose between A and D as shown in Figure
.In this case, we must go to D then to A so that we can visit C without backtracking. The complete Hamilton path is shown in Figure
.So, one Hamilton path that begins at O and ends at C is O → Q → M → R → S → B → E → G → H → L → N → K → J → P → I → F → D → A → C .
There is no set sequence of steps that can be used to find a Hamilton path if it exists, but it does help to keep in mind where we are headed and avoid choices that will make returning to a particular vertex impossible without repeating vertices. Let’s practice finding Hamilton paths.
Use Figure
to find a Hamilton path between vertices C and D .Use Figure
to find a Hamilton path between vertices C and E .Existence of a Hamilton Path
It turns out that there is no Hamilton path between vertices A and E in Graph G in Figure
. To understand why, let’s imagine there is a red apple tree on one side of a bridge and a green apple tree on the other side of the bridge. Now suppose someone asked you to pick up all the fallen apples under each tree without crossing the bridge more than once, and making sure that the first apple you pick up and the last apple you pick up are both red. You would say, that is impossible! To have the first and last apple be red would either require leaving the green apples on the ground or crossing the bridge twice.Let’s see how this relates to finding a Hamilton path between A and E in Graph G . The edge AC is a bridge because, if it were removed, the graph would become disconnected with two components, the component { C } and the component { A , B , D , E , F }. So, we can think of the vertices A , B , D , E , and F as the red apples, vertex C as the green apple, and the edge AC is the bridge between them as in Figure
.The creation of a Hamilton path requires a visit to each vertex, just as picking up all the apples requires a visit to each apple. A and E are both red apples; so, a path from A to E would both start and end at a red apple, just as you were asked to do. And you wouldn’t be able to cross the bridge twice because that would mean visiting A twice, which is not allowed in a Hamilton path. So, it is impossible to find a Hamilton path from A to E just as it was impossible to pick up all the apples without crossing the bridge more than once. By the same reasoning, if a graph has a bridge, there will never be a Hamilton path that begins and ends on the same side of that bridge, meaning beginning and ending at vertices that would be in the same component if the bridge were removed from the graph.
Find a Hamilton path from vertex s to vertex v for each graph in Figure
or indicate that there is none.- Answer
-
Graph A : Edge uw is a bridge connecting component { s , t , u , v } to the component { w , x , y , z }. There is no Hamilton path from vertex s to vertex v because they would be part of the same component if the bridge uw were removed.
Graph B : There are no bridges in Graph B . The only method we have to determine if a Hamilton path from vertex s to vertex v exists is to try every possibility. From vertex s , we can visit either vertex y or vertex t . We will try vertex y first and then come back to see what happens with vertex t . After visiting y , we must visit z and then u , but then we have to decide between vertices r , t , and v next as shown in Figure
. - Vertex v is not an option since we want to end at v . Vertex t is not an option since that would force us to go to visit s a second time. So, we must go to vertex r next. After vertex r , we must visit x , then w , then v , but we missed vertex t as shown in Figure .
-
Let’s go back to the beginning and choose t instead of y . After t , we must go to u and then we have a choice to make between r , v , and z as shown in Figure
Vertex v is not an option since we want to end at v . Vertex z is not an option since that would force us to go y and then to visit s a second time. So, we must go to vertex r next. After r , we must go to x then w then v , where we have to stop even though we have missed vertices y and z , as shown in Figure . . So, we have tried every possible route and there are no Hamilton paths between s and v in Graph B .Graph C : In Graph C , there is a Hamilton path, s → t → u → x → w → v .
Graph D : In Graph D , there is a bridge, tx , which would form components { r , s , t , u , q } and { v , w , x , y , z } if it were removed. Since s and v would be in different components, it is possible there is a Hamilton path between them. The only way to know is to try all possibilities. If we begin at s , we can go to r then t , or we can go directly to t , either way, we have a problem as you can see in Figure
.If we visit all the vertices in the component { r , s , t , u , q }, we will have to visit t a second time in order to cross the bridge. If we visit t only once, we have to skip some of the vertices. So, there is no Hamilton path between s and v .
Use Graph L to find a Hamilton path between each pair of vertices or indicate that there isn’t one.
- p to r
- m to p
- o to q
There is not a short way to determine if there is a Hamilton path between two vertices on a graph that works in every situation. However, there are a few common situations that can help us to quickly determine that there is no Hamilton path. Some of these are listed in Table
.| Scenario | Diagram |
|---|---|
| Scenario 1 If an edge ab is a bridge, then there is no Hamilton path between a pair of vertices that are on the same side of edge ab . We saw this in Graph A of Example 12.40. | |
| Scenario 2 If an edge ab is a bridge with at least three components on each side, then there is no Hamilton path beginning or ending at a or b . We saw this in Graph D of Example 12.40. |
No Hamilton path beginning or ending at a or b . |
| Scenario 3 If a graph is composed of two cycles joined only at a single vertex p , and v is any vertex that is NOT adjacent to p , then there are no Hamilton paths beginning or ending at p . We saw this in Graph B of Example 12.40. |
No Hamilton path can be formed starting or ending at vertices, r , v , or u because they are not adjacent to p . |
There are also many other situations in which a Hamilton path is not possible. These are just a few that you will encounter.
Hamilton Path or Euler Trail?
We learned in Euler Trails that an Euler trail visits each edge exactly once, whereas a Hamilton path visits each vertex exactly once. Let’s practice distinguishing between the two.
Use Figure
Figure to determine if the given sequence of vertices is a Hamilton path, an Euler trail, both, or neither.- Graph A , e → b → a → e → d → c → b
- Graph F , f → g → j → h → i
- Graph K , k → l → m → n → o\
- Answer
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- Since the sequence covers every edge once but visits vertices more than once, it is only an Euler trail.
- Since the sequence visits every vertex exactly once but skips some edges, it is only a Hamilton path.
- Since the sequence visits each edge and each vertex exactly once, it is both an Euler trail and a Hamilton path.
Use Figure 12.262 to determine if the given sequence of vertices is a Hamilton path, an Euler trail, both, or neither.
Graph A , a → b → e → d → c
Graph F , g → h → i → j → h → f → g → j → f → i
Graph K , o → n → m → l
As we saw the Emerald City lies at the center of the Magical Land of Oz, with Gillikin Country to the north, Winkie Country to the east, Munchkin Country to the west, and Quadling Country to the south. Munchkin Country and Winkie Country each shares a border with Gillikin Country and Quadling Country. Let’s apply graph theory to Dorothy’s famous journey through Oz one more time!
Draw a graph in which each vertex is one of the regions of Oz. Is there a Hamilton path that Dorothy could follow, instead of the yellow brick road, to lead her from the land of the Munchkins, through all the regions of Oz exactly once, and end in the Emerald City? If so, what might it be? Compare your results with those of a classmate.
Check Your Understanding
- For the following exercises, fill in the blank with the same as or different from to make the statement true.
- Unlike in a Hamilton cycle, the vertex where the Hamilton path begins is _________ the vertex where the Hamilton path ends.
- If a sequence of vertices represents a Hamilton path, the number of vertices listed should be _______ the number of vertices in the whole graph.
- To determine if a graph has a Hamilton path, use a method that is _________ the method used to determine if a graph has an Euler trail.
- If a graph with a bridge has a Hamilton path, the starting vertex should be on the side of the bridge that is ________ the side of the bridge with the ending vertex.
6. A path between two vertices of a graph that visits each vertex of the graph exactly once is called an Euler path
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True
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False
7. Any graph that has exactly two vertices of odd degree has a Hamilton path.
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True
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False
8. If a graph is composed of two cycles joined only at a single vertex p , then no Hamilton path can be formed starting or ending at any vertex that is adjacent to p .
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True
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False
9. If an edge ab is a bridge with at least three components on each side, then there is no Hamilton path between vertex a and any vertex on the other side of edge ab .
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True
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False


6.4: Identifier Names
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Overview
Within programming a variety of items are given descriptive names to make the code more meaningful to us as humans. These names are called “Identifier Names”. Constants, variables, type definitions, functions, etc. when declared or defined are identified by a name. These names follow a set of rules that are imposed by:
- the language’s technical limitations
- good programming practices
- common industry standards for the language
Discussion
Technical to Language
- Use only allowable characters (in many languages the first character must be alphabetic or underscore, can continue with alphanumeric or underscore)
- Can’t use reserved words
- Length limit
These attributes vary from one programming language to another. The allowable characters and reserved words will be different. The length limit refers to how many characters are allowed in an identifier name and often is compiler dependent and may vary from compiler to compiler for the same language. However, all programming languages have some form of the technical rules listed here.
Good Programming Techniques
- Meaningful
- Be case consistent
Meaningful identifier names make your code easier for another to understand. After all what does “p” mean? Is it pi, price, pennies, etc. Thus do not use cryptic (look it up in the dictionary) identifier names.
Some programming languages treat upper and lower case letters used in identifier names as the same.  Unknown to you the programmer, the compiler usually forces all identifier names to upper case. Thus: pig and Pig both get changed to PIG. However, not all programming languages act this way. Some will treat upper and lower case letters as being different things. Thus: pig and Pig are two different identifier names. If you declare it as pig and then reference it in your code later as Pig – you get a different variable or perhaps a compiler error. To avoid the problem altogether, we teach students to be case consistent . Use an identifier name only one way and spell it (upper and lower case) the same way every time within your program.
Industry Rules
Almost all programming languages and most coding shops have a standard code formatting style guide programmers are expected to follow. Among these are three common identifier casing standards:
- camelCase – each word is capitalized except the first word, with no intervening spaces
- PascalCase – each word is capitalized including the first word, with no intervening spaces
- snake_case – each word is lowercase with an underscores separating words
C++, Java, and JavaScript typically use camelCase, with PascalCase reserved for libraries and classes. C# uses primarily PascalCase with camelCase parameters. Python uses snake_case for most identifiers. In addition, the following rules apply:
- Do not start with an underscore (used for technical programming)
- CONSTANTS IN ALL UPPER CASE (often UPPER_SNAKE_CASE).
These rules are decided by the industry (those who are using the programming language).
Key Terms
- camel case
- The practice of writing compound words or phrases such that each word or abbreviation in the middle of the phrase begins with a capital letter, with no intervening spaces or punctuation.
- Pascal case
- The practice of writing compound words or phrases such that each word or abbreviation in the phrase begins with a capital letter, including the first letter, with no intervening spaces or punctuation.
- reserved word
- Words that cannot be used by the programmer as identifier names because they already have a specific meaning within the programming language.
- snake case
- The practice of writing compound words or phrases in which the elements are separated with one underscore character (_) and no spaces, with each element’s initial letter usually lowercased within the compound and the first letter either upper or lower case.


2.3: Only Geniuses can be Writers
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- Cheryl E. Ball & Drew M. Loewe ed.
- West Virginia University via Digital Publishing Institute and West Virginia University Libraries
Authors: Dustin Edwards @edwardsdusty, Enrique Paz @eepaziii Southern Illinois University Carbondale
Our American culture and education has cultivated quite the romantic idea of authorship. Instruction in language arts and literature consistently and often forcefully exposes students to writers who have been canonized as The Greats: geniuses of thought, master wordsmiths, and inspired creators—in a word, authors— who transcended humanity and mortality. Shakespeare, Emerson, Orwell, and so on—these were truly writers!—they say. These writers sat at grand mahogany desks in remote cabins ensconced in the most still and people-less of lakes and forests. These writers sequestered themselves from all influence and feverishly scribed brilliant works only their peerless minds could produce. But these writers, great as they may be, have been the most damaging to our current perceptions about writing.
The image of this autonomous, genius, and originary author bears great consequences; it designates a coveted status against which many, if not all, writers are compared. It is etched into intellectual property debates, woven into anxieties and uncertainties over plagiarism, and intricately bound to the economics of writing. Worst of all, it stubbornly refuses to die, despite persistent attempts to overthrow its reign on literacy instruction and cultural production.
The Weight of Genius
As graduates of U.S. education, we’ve personally experienced (and continue to experience) the damage this myth has wrought on those who write. The genius writers were enlightened, wise, and shrewd observers of the world and humanity. They wrote the truth as only they could, and that fount flowed freely and easily. But that’s not how writing works for us. Writing is hard . So many writing tasks we meet are impenetrable, fortified on every side with
bulwarks tall and steel. We pound and press against those walls— but nothing. Our work often stalls out, halted in place. We obviously cannot be true authors, right? This should be that easy. Why doesn’t it just come out?
These genius authors misguide many writers. Their most damaging effects are the unrealistic expectations they pose for everyday writers. Writing scholar and plagiarism expert Rebecca Moore Howard believes the notion of the solitary, genius author has perpetuated a climate where novice writers fear being unoriginal and must strive to prove their own creativity and genius. You need only glance at the branding language of the plagiarism detection service Turnitin, a self-proclaimed “originality-checker,” to see how this manifests in real-life scenarios. The demand for originality frustrates many writers, who do not see how they could ever have the genius to discover an original thought.
Other writers, both within and outside of academic settings, similarly struggle when they feel their writing process doesn’t live up to the lauded image of The Greats. In a short essay in The Irish Times , author and musician Josh Ritter writes about how he wrestled with the image of genius authors. He never felt his songwriting counted as real writing, which can only happen upon grand escritoires, penned with quill and ink and set in parchment. He writes, “Never mind that for my entire writing life I’d been writing at my kitchen table, with my guitar on my knee and a pen and notebook handy, if I wanted to be a real writer, I would need a desk. [...] And without the desk, how could I write my novel?” Ritter finds himself limited by the image of writing and writers that a desk represents. Without a desk, Ritter can’t imagine he has the ability to produce a worthy piece of writing, just as many don’t feel like true writers if they struggle and strive when they write. But Ritter comes to a conclusion we also share: remote cabins along isolated lakes, grand writing tables carved from cedars, brilliant manuscripts born in one candlelit sitting—these don’t accurately represent what writing looks like for anyone.
Well-hidden between pristine white pages and well-crafted words lies the same trying process many endure each time they open a document or hold a pen as well as the same unyielding barricades that keep them out, which often only give way when they are influenced and inspired by others. Tales of genius writers who pour out perfectly structured prose all on their own recount fables rather than reality. (See Teri Holbrook and Melanie Hundley’s chapter elsewhere in this book for more on bad myths about writers.) Instead, these writers were certainly very much like ourselves—nervous, frustrated, harried, and tired, looking for help at 1:38 a.m. while trying to meet a deadline. What help we do find rarely comes from genius, self-willed epiphanies. Instead, we find solace, support, and success when we look outside ourselves, borrow ideas, remix other texts, talk to others, and collaborate with their thoughts. The Lone Genius author doesn’t exist. And it never did.
Yet, such an understanding of authorship has become so commonplace, so naturalized, that few ever interrogate its origins. A closer look at this myth reveals that the author was forged only recently in Western history. According to literary historian Martha Woodmansee, the invention of the author in its current configuration can be traced to 1st-century Europe. It was during this century, according to Woodmansee’s analysis, when a larger cultural shift began to take place, and out of a swirl of change—technological, legal, economic, and cultural—a new definition of the contemporary author began to emerge. This is the author that largely sticks today: the creator, owner, and proprietor of unique, original works such as essays, books, poems, and so on.
The Invention of Genius
Views of writing that lead to modern ideals about authors developed along with the circulation of popular treatises on originality. In 1759, for example, the influential writer and poet Edward Young’s “Conjectures on Original Composition” began to draw deep divides between original and imitative authorship. Originality, Young claimed, sprung forth naturally from an inherent root of genius, like a plant bearing fruit. Imitations, on the other hand, were artificial inferiors built from the work of others. Young’s essay, and many others like it, began to forcefully redirect the locus of inspiration. They claimed that true authors are not inspired by the outside world; they are inspired by their unique selves. True authors are not imitators; they are originators. True authors are not made; they are born.
This redirection of inspiration also coincided with the birth of a new class of writers: professional authors. Now, essayists, poets, and other public intellectuals claimed an occupation where writing was their primary means for earning a living. Thanks in large part to the expansion of a larger reading public due to advances in
printing technology, a need grew to find ways for professional writers (and the publishing industry) to earn money from their printed works. Enter copyright. Early copyright laws, according to historian Mark Rose’s analysis of copyright, helped to form an understanding of the author as an owner and proprietor of his or her individual ideas. In other words, copyright helped to define the author as author: an autonomous individual whose original ideas merit legal protection and deserve monetary rewards.
There are many reasons why this understanding of the author persists today. Tenets of originality, property, proprietorship, and genius have become etched into the fabric of Western authorship. Genius authorship is coded into our legal and economic systems and is further upheld through years of education. Our understandings of an author are also a product of the publishing industry itself. Publishers present a polished and finalized copy of writing and thereby dilute the messiness of the writing process. The idea that authors derive their writing abilities from their natural intellect is difficult to shake because it is inscribed in the very word author itself.
But such was not always the case. A deeper look at history, together with today’s digital writing practices, reveals how the myth of the lone, original genius can be challenged. Specifically, alternatives to genius see value in imitation, collaboration, and remix. Authors don’t act in isolation but rather find themselves surrounded by other ideas, people, and writing.
The Alternative to Genius
Before the idea of genius authorship took hold, Woodmansee notes that authors were commonly depicted either as vehicles (receiving ideas from some outside source) or craftsmen (forging new materials out many disparate sources). An even deeper history reveals a more esteemed regard for imitation. Practices of imitation—drawing inspiration from outside sources by borrowing, adapting, and altering models from a rich stockpile of sources— were largely valued in ancient cultures. Imitation was how students learned their craft, and it was viewed as a way to invent new meanings out of existing materials. In fact, ancient philosophers and poets often used the metaphor of a transformative bee to describe the work of imitation. As Seneca described in the 4th century BCE, “We should follow, men say, the example of the bees, who flit about and cull the flowers that are suitable for producing honey, and then arrange and assort in their cells all that they have brought in.” This metaphor suggests the act of producing a new work involves gathering bits and pieces from many different external sources.
These historical practices and ideas about authorship demonstrate what writing once was and what we believe it still should be: a collaborative endeavor in constant and deep conversation with the works and ideas of others. In other words, instead of the reclusive genius, we aim to be social writers. Instead of inspiration from within, we seek influence from without. Writing requires talking to friends, asking help from colleagues, finding answers and ideas in others’ writings, and indulging in those practices. We embrace collaboration over isolation, and it is precisely this model of writing that we argue education should promote to writers and students everywhere.
In a way, it’s odd to call for more collaborative writing or writing influenced by others, because it’s already happening everywhere. Many scholars attest that collaboration, rather than isolation, is the dominant approach to everyday composing. Writing scholars Lisa Ede and Andrea Lunsford, for example, have studied the work of writers in diverse fields, including engineering, psychology, chemistry, and even sanitation. They find that the professionals in these fields rely heavily on collaboration to succeed in their writing tasks. Likewise, writing researcher Joan Mullin confirms that many artists—painters, architects, fashion designers, graphic artists and more—always feel their work is collaborative and often learn by mimicking, imitating, and even copying the work of others. These writers and artists rely heavily on others’ thoughts and ideas to help them learn and succeed, and their success exemplifies why this should be the default approach to all writing.
What’s more, collaboration involves more than the act of writing with other warm bodies in the room. It also involves a different kind of collaboration: reusing, recycling, and repurposing existing materials for new uses. In our digital age, everyday people increasingly have access to vast reservoirs of archived materials. Significantly, these materials can be put to use for new purposes. Rhetoric scholars Jim Ridolfo and Dànielle Nicole DeVoss refer to this remix process as “taking old pieces of text, images, sounds, and video and stitching them together to form a new product.” Writing, if viewed this way, isn’t predicated on values of isolation, inward inspiration, or originality; rather, it sees values in sharing, explicit influence, and renewal. Perhaps surprisingly, as media researcher Henry Jenkins notes, the language of remix resuscitates
older, pre-Romantic ideals of authorship. A turn toward remix and borrowing, for Jenkins, “is not that radical when read against a larger backdrop of human history,” despite the deeply entrenched ideal of creative genius propagated in recent history.
As both history and contemporary practice demonstrate, writing has always required deep social engagement and influence, and no writer has succeeded solely due to preternatural intellect or talent. The pervasive idea of the reclusive author and genius birthing prose free from influence must die—and in its wake, a renewed idea of productive and meaningful collaboration (with other writers and their texts) will thrive.
Further Reading
To learn more about how today’s writers actually compose, consider Lisa Ede and Andrea Lunsford’s Singular Texts/Plural Authors : Perspectives in Collaborative Writing (Southern Illinois University Press), Carol Petersen Haviland and Joan A. Mullin’s Who Owns This Text?: Plagiarism, Authorship, and Disciplinary Cultures (Utah State University Press), Majorie Perloff’s Unoriginal Genius: Poetry by Other Means in the New Century (University of Chicago Press), and Kevin Goldsmith’s Uncreative Writing: Managing Language in the Digital Age (Columbia University Press). Additionally, Josh Ritter’s article “Paperback Ritter” is his story about how he personally was affected by myths of authorship while writing his book .
For more on remix, look into Lawrence Lessig’s Remix: Making Art and Commerce Thrive in the Hybrid Economy (Penguin Press), Jim Ridolfo and Dànielle Nicole DeVoss’s “Composing for Recomposition: Rhetorical Velocity and Delivery,” Kirby Ferguson’s web series Everything is a Remix , and Jonathan Lethem’s article “The Ecstasy of Influence: A Plagiarism” in Harper’s Magazine .
Conversations about originality often intersect with questions about plagiarism. To explore this connection more, see Rebecca Moore Howard’s Standing in the Shadows of Giants: Plagiarists, Authors, and Collaboration (Ablex), Susan Blum’s My Word! Plagiarism and College Culture (Cornell University Press), and Nicolous Kulish’s New York Times article about author Helene Hegemann’s best-selling book, controversial for its plagiarized passages.
To read more on the history and theory of authorship, look to Andrew Gallax’s “In Theory: The Death of the Author,” Mark Rose’s Authors and Owners: The Invention of Copyright (Harvard University Press), and Martha Woodmansee’s article “The Genius and the
Copyright: Economic and Legal Conditions of the Emergence of the ‘Author’” ( Eighteenth Century Studies ).
Keywords
authorship, collaboration, genius, history of authorship, influence, originality, remix
Author Bios
Dustin Edwards’s research focuses on writing in digital environments, intellectual property, and authorship studies. He has written about how writing for extracurricular, professional, and civic purposes can—and should—influence the teaching of writing in university settings. He can be reached on Twitter @edwardsdusty.
Enrique Paz studies authorship and plagiarism and teaches writing. He’s interested in how people come to see themselves as writers or authors. Working with many other writers, he’s published essays on how writers can collaborate effectively and specifically how educators and students can and should collaborate to promote learning and success. You can find him on Twitter @eepaziii.