7.11: Facts About the F Distribution
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Here are some facts about the \(F\) distribution:
- The curve is not symmetrical but skewed to the right.
- There is a different curve for each set of \(dfs\).
- The \(F\) statistic is greater than or equal to zero.
- As the degrees of freedom for the numerator and for the denominator get larger, the curve approximates the normal.
- Other uses for the \(F\) distribution include comparing two variances and two-way Analysis of Variance. Two-Way Analysis is beyond the scope of this chapter.
Example \(\PageIndex{1}\)
Let’s return to the slicing tomato exercise. The means of the tomato yields under the five mulching conditions are represented by \(\mu_{1}, \mu_{2}, \mu_{3}, \mu_{4}, \mu_{5}\). We will conduct a hypothesis test to determine if all means are the same or at least one is different. Using a significance level of 5%, test the null hypothesis that there is no difference in mean yields among the five groups against the alternative hypothesis that at least one mean is different from the rest.
Answer
The null and alternative hypotheses are:
- \(H_{0}: \mu_{1} = \mu_{2} = \mu_{3} = \mu_{4} = \mu_{5}\)
- \(H_{a}: \mu_{i} \neq \mu_{j}\) some \(i \neq j\)
The one-way ANOVA results are shown in Table
| Source of Variation | Sum of Squares (\(SS\)) | Degrees of Freedom (\(df\)) | Mean Square (\(MS\)) | \(F\) |
|---|---|---|---|---|
| Factor (Between) | 36,648,561 | \(5 - 1 = 4\) | \(\dfrac{36,648,561}{4} = 9,162,140\) |
\(\dfrac{9,162,140}{2,044,672.6} = 4.4810\) |
| Error (Within) | 20,446,726 | \(15 - 5 = 10\) |
\(\dfrac{20,446,726}{10} = 2,044,672.6\) |
|
| Total | 57,095,287 | \(15 - 1 = 14\) |
Distribution for the test: \(F_{4,10}\)
\[df(\text{num}) = 5 - 1 = 4\]
\[df(\text{denom}) = 15 - 5 = 10\]
Test statistic: \(F = 4.4810\)
Probability Statement: \(p\text{-value} = P(F > 4.481) = 0.0248\).
Compare \(\alpha\) and the \(p\text{-value}\) : \(\alpha = 0.05, p\text{-value} = 0.0248\)
Make a decision: Since \(\alpha > p\text{-value}\), we reject \(H_{0}\).
Conclusion: At the 5% significance level, we have reasonably strong evidence that differences in mean yields for slicing tomato plants grown under different mulching conditions are unlikely to be due to chance alone. We may conclude that at least some of mulches led to different mean yields.
To find these results on the calculator:
Press STAT. Press 1:EDIT. Put the data into the lists L 1 , L 2 , L 3 , L 4 , L 5 .
Press STAT, and arrow over to TESTS, and arrow down to ANOVA. Press ENTER, and then enter L 1 , L 2 , L 3 , L 4 , L 5 ). Press ENTER. You will see that the values in the foregoing ANOVA table are easily produced by the calculator, including the test statistic and the p -value of the test.
The calculator displays:
- \(F = 4.4810\)
- \(p = 0.0248\) (\(p\text{-value}\))
Factor
- \(df = 4\)
- \(SS = 36648560.9\)
- \(MS = 9162140.23\)
Error
- \(df = 10\)
- \(SS = 20446726\)
- \(MS = 2044672.6\)
Exercise \(\PageIndex{1}\)
MRSA, or Staphylococcus aureus , can cause a serious bacterial infections in hospital patients. Table shows various colony counts from different patients who may or may not have MRSA.
| Conc = 0.6 | Conc = 0.8 | Conc = 1.0 | Conc = 1.2 | Conc = 1.4 |
|---|---|---|---|---|
| 9 | 16 | 22 | 30 | 27 |
| 66 | 93 | 147 | 199 | 168 |
| 98 | 82 | 120 | 148 | 132 |
Plot of the data for the different concentrations:
Test whether the mean number of colonies are the same or are different. Construct the ANOVA table (by hand or by using a TI-83, 83+, or 84+ calculator), find the p -value, and state your conclusion. Use a 5% significance level.
Answer
While there are differences in the spreads between the groups (Figure \(\PageIndex{1}\)), the differences do not appear to be big enough to cause concern.
We test for the equality of mean number of colonies:
\(H_{0}: \mu_{1} = \mu_{2} = \mu_{3} = \mu_{4} = \mu_{5}\)
\(H_{a}: \mu_{i} \neq \mu_{j}\) some \(i \neq j\)
The one-way ANOVA table results are shown in Table.
| Source of Variation | Sum of Squares (\(SS\)) | Degrees of Freedom (\(df\)) | Mean Square (\(MS\)) | \(F\) |
|---|---|---|---|---|
| Factor (Between) | 10,233 | \(5 - 1 = 4\) | \(\dfrac{10,233}{4} = 2,558.25\) | \(\dfrac{2,558.25}{4,194.9} = 0.6099\) |
| Error (Within) | 41,949 | \(15 - 5 = 10\) | ||
| Total | 52,182 | \(15 - 1 = 14\) | \(\dfrac{41,949}{10} = 4,194.9\) |
Figure \(\PageIndex{2}\)
Distribution for the test: \(F_{4,10}\)
Probability Statement: \(p\text{-value} = P(F > 0.6099) = 0.6649\).
Compare \(\alpha\) and the \(p\text{-value}\) : \(\alpha = 0.05, p\text{-value} = 0.669, \alpha > p\text{-value}\)
Make a decision: Since \(\alpha > p\text{-value}\), we do not reject \(H_{0}\).
Conclusion: At the 5% significance level, there is insufficient evidence from these data that different levels of tryptone will cause a significant difference in the mean number of bacterial colonies formed.
Example \(\PageIndex{2}\)
Four sororities took a random sample of sisters regarding their grade means for the past term. The results are shown in Table.
| Sorority 1 | Sorority 2 | Sorority 3 | Sorority 4 |
|---|---|---|---|
| 2.17 | 2.63 | 2.63 | 3.79 |
| 1.85 | 1.77 | 3.78 | 3.45 |
| 2.83 | 3.25 | 4.00 | 3.08 |
| 1.69 | 1.86 | 2.55 | 2.26 |
| 3.33 | 2.21 | 2.45 | 3.18 |
Using a significance level of 1%, is there a difference in mean grades among the sororities?
Answer
Let \(\mu_{1}, \mu_{2}, \mu_{3}, \mu_{4}\) be the population means of the sororities. Remember that the null hypothesis claims that the sorority groups are from the same normal distribution. The alternate hypothesis says that at least two of the sorority groups come from populations with different normal distributions. Notice that the four sample sizes are each five.
This is an example of a balanced design, because each factor (i.e., sorority) has the same number of observations.
\(H_{0}: \mu_{1} = \mu_{2} = \mu_{3} = \mu_{4}\)
\(H_{a}\): Not all of the means \(\mu_{1}, \mu_{2}, \mu_{3}, \mu_{4}\) are equal.
Distribution for the test: \(F_{3,16}\)
where \(k = 4\) groups and \(n = 20\) samples in total
\(df(\text{num}) = k - 1 = 4 - 1 = 3\)
\(df(\text{denom}) = n - k = 20 - 4 = 16\)
Calculate the test statistic: \(F = 2.23\)
Graph:
Probability statement: \(p\text{-value} = P(F > 2.23) = 0.1241\)
Compare \(\alpha\) and the \(p\text{-value}\) : \(\alpha = 0.01\)
\(p\text{-value} = 0.1241\)
\(\alpha < p\text{-value}\)
Make a decision: Since \(\alpha < p\text{-value}\), you cannot reject \(H_{0}\).
Conclusion: There is not sufficient evidence to conclude that there is a difference among the mean grades for the sororities.
Put the data into lists L
1
, L
2
, L
3
, and L
4
. Press
STAT
and arrow over to
TESTS
. Arrow down to
F:ANOVA
. Press
ENTER
and Enter (
L1,L2,L3,L4
).
The calculator displays the F statistic, the \(p\text{-value}\) and the values for the one-way ANOVA table:
\(F = 2.2303\)
\(p = 0.1241\) (\(p\text{-value}\))
Factor
\(df = 3\)
\(SS = 2.88732\)
\(MS = 0.96244\)
Error
\(df = 1\)
\(SS = 6.9044\)
\(MS = 0.431525\)
Exercise \(\PageIndex{2}\)
Four sports teams took a random sample of players regarding their GPAs for the last year. The results are shown in Table.
| Basketball | Baseball | Hockey | Lacrosse |
|---|---|---|---|
| 3.6 | 2.1 | 4.0 | 2.0 |
| 2.9 | 2.6 | 2.0 | 3.6 |
| 2.5 | 3.9 | 2.6 | 3.9 |
| 3.3 | 3.1 | 3.2 | 2.7 |
| 3.8 | 3.4 | 3.2 | 2.5 |
Use a significance level of 5%, and determine if there is a difference in GPA among the teams.
Answer
With a \(p\text{-value}\) of \(0.9271\), we decline to reject the null hypothesis. There is not sufficient evidence to conclude that there is a difference among the GPAs for the sports teams.
Example \(\PageIndex{3}\)
A fourth grade class is studying the environment. One of the assignments is to grow bean plants in different soils. Tommy chose to grow his bean plants in soil found outside his classroom mixed with dryer lint. Tara chose to grow her bean plants in potting soil bought at the local nursery. Nick chose to grow his bean plants in soil from his mother's garden. No chemicals were used on the plants, only water. They were grown inside the classroom next to a large window. Each child grew five plants. At the end of the growing period, each plant was measured, producing the data (in inches) in Table \(\PageIndex{3}\).
| Tommy's Plants | Tara's Plants | Nick's Plants |
|---|---|---|
| 24 | 25 | 23 |
| 21 | 31 | 27 |
| 23 | 23 | 22 |
| 30 | 20 | 30 |
| 23 | 28 | 20 |
Does it appear that the three media in which the bean plants were grown produce the same mean height? Test at a 3% level of significance.
Answer
This time, we will perform the calculations that lead to the \(F'\) statistic. Notice that each group has the same number of plants, so we will use the formula
\[F' = \dfrac{n \cdot s_{\bar{x}}^{2}}{s^{2}_{\text{pooled}}}.\]
First, calculate the sample mean and sample variance of each group.
| Tommy's Plants | Tara's Plants | Nick's Plants | |
|---|---|---|---|
| Sample Mean | 24.2 | 25.4 | 24.4 |
| Sample Variance | 11.7 | 18.3 | 16.3 |
Next, calculate the variance of the three group means (Calculate the variance of 24.2, 25.4, and 24.4). Variance of the group means \(= 0.413 = s_{\bar{x}}^{2}\)
Then \(MS_{\text{between}} = ns_{\bar{x}}^{2} = (5)(0.413)\) where \(n = 5\) is the sample size (number of plants each child grew).
Calculate the mean of the three sample variances (Calculate the mean of 11.7, 18.3, and 16.3). Mean of the sample variances \(= 15.433 = s^{2}_{\text{pooled}}\)
Then \(MS_{\text{within}} = s^{2}_{\text{pooled}} = 15.433\).
The \(F\) statistic (or \(F\) ratio) is \(F = \dfrac{MS_{\text{between}}}{MS_{\text{within}}} = \dfrac{ns_{\bar{x}}^{2}}{s^{2}_{\text{pooled}}} = \dfrac{(5)(0.413)}{15.433} = 0.134\)
The \(dfs\) for the numerator \(= \text{the number of groups} - 1 = 3 - 1 = 2\).
The \(dfs\) for the denominator \(= \text{the total number of samples} - \text{the number of groups} = 15 - 3 = 12\)
The distribution for the test is \(F_{2,12}\) and the \(F\) statistic is \(F = 0.134\)
The \(p\text{-value}\) is \(P(F > 0.134) = 0.8759\).
Decision: Since \(\alpha = 0.03\) and the \(p\text{-value} = 0.8759\), do not reject \(H_{0}\). (Why?)
Conclusion: With a 3% level of significance, from the sample data, the evidence is not sufficient to conclude that the mean heights of the bean plants are different.
To calculate the \(p\text{-value}\):
*Press
2nd DISTR
*Arrow down to
Fcdf
(and press
ENTER
.
*Enter 0.134,
E99
, 2, 12)
*Press
ENTER
The \(p\text{-value}\) is \(0.8759\).
Exercise \(\PageIndex{3}\)
Another fourth grader also grew bean plants, but this time in a jelly-like mass. The heights were (in inches) 24, 28, 25, 30, and 32. Do a one-way ANOVA test on the four groups. Are the heights of the bean plants different? Use the same method as shown in Example \(\PageIndex{3}\).
Answer
- \(F = 0.9496\)
- \(p\text{-value} = 0.4402\)
From the sample data, the evidence is not sufficient to conclude that the mean heights of the bean plants are different.
Collaborative Exercise
From the class, create four groups of the same size as follows: men under 22, men at least 22, women under 22, women at least 22. Have each member of each group record the number of states in the United States he or she has visited. Run an ANOVA test to determine if the average number of states visited in the four groups are the same. Test at a 1% level of significance. Use one of the solution sheets in [link].
References
- Data from a fourth grade classroom in 1994 in a private K – 12 school in San Jose, CA.
- Hand, D.J., F. Daly, A.D. Lunn, K.J. McConway, and E. Ostrowski. A Handbook of Small Datasets: Data for Fruitfly Fecundity. London: Chapman & Hall, 1994.
- Hand, D.J., F. Daly, A.D. Lunn, K.J. McConway, and E. Ostrowski. A Handbook of Small Datasets. London: Chapman & Hall, 1994, pg. 50.
- Hand, D.J., F. Daly, A.D. Lunn, K.J. McConway, and E. Ostrowski. A Handbook of Small Datasets. London: Chapman & Hall, 1994, pg. 118.
- “MLB Standings – 2012.” Available online at http://espn.go.com/mlb/standings/_/year/2012 .
- Mackowiak, P. A., Wasserman, S. S., and Levine, M. M. (1992), "A Critical Appraisal of 98.6 Degrees F, the Upper Limit of the Normal Body Temperature, and Other Legacies of Carl Reinhold August Wunderlich," Journal of the American Medical Association , 268, 1578-1580.
Review
The graph of the \(F\) distribution is always positive and skewed right, though the shape can be mounded or exponential depending on the combination of numerator and denominator degrees of freedom. The \(F\) statistic is the ratio of a measure of the variation in the group means to a similar measure of the variation within the groups. If the null hypothesis is correct, then the numerator should be small compared to the denominator. A small \(F\) statistic will result, and the area under the \(F\) curve to the right will be large, representing a large \(p\text{-value}\). When the null hypothesis of equal group means is incorrect, then the numerator should be large compared to the denominator, giving a large \(F\) statistic and a small area (small \(p\text{-value}\)) to the right of the statistic under the \(F\) curve.
When the data have unequal group sizes (unbalanced data), then techniques discussed earlier need to be used for hand calculations. In the case of balanced data (the groups are the same size) however, simplified calculations based on group means and variances may be used. In practice, of course, software is usually employed in the analysis. As in any analysis, graphs of various sorts should be used in conjunction with numerical techniques. Always look of your data!


7.3: Influences on Emotional Expression
Emotions and Experience
There are many influences on our emotional expression. These influences help shape the way we perceive and interact with our emotions. We may think that our emotions are singular and not attached to other emotions and experiences. In this section we clarify how our emotions affect other emotions and experiences. We focus on how we interpret and react differently based on our own personality traits, our cultural background, and how our culture and society itself shape not only the emotions we experience, but how we react in communication events.
Personality
Emotions are an important aspect in how we build our social interactions with people around us. Whether strangers or people who have a significant impact on our lives, people tend to consciously or unconsciously work at monitoring, observing, and regulating emotions around others. Our interactions with others help to shape our own emotions as well as aspects of our personalities and moods. But what is the difference between these terms? We’ve defined emotion earlier in this chapter, but how do we know the distinction between what is an emotion, what is a mood, and what is part of our personality?
The biggest difference is the longevity of the feeling. Where emotions may last seconds to minutes, moods can last hours to days. A mood is built from the collection of emotions and feelings, whereas personality is built from stable sets of moods and traits such as social interactions, behaviors, and values, as well as cultural and environmental factors.
One of our authors shares her example:
I can confidently say that I have a “grumpy” personality. Even photos of me as a young child showcase that I tend to have a pout on my face, and I pride myself in being able to think of the “glass as half empty” more often than not. This is part of my personality that I own and accept. Although I may have what I consider a “grumpy” personality, that does not mean every day of my life is lived in a bad mood. I, like all of us, have days, weeks and months filled with good moods, but I also experience bad moods from time to time. I share laughter and joyful emotions with friends and loved ones regularly, as well as feeling emotions of love and grief equally. While I may say my personality is “grumpy” I would say my mood tends to be positive, and my emotions tend to be neutral.
Personality can be seen as a dimension of an individual, where the aspects of what we think, feel, and the ways in which we behave based on our emotions are constructed to make up our unique personality in specific ways (Filipiak & Łubianka, 2021). When looking at personality, research has consistently found that there tends to be five major dimensions called Big Five personality traits.
The Big Five personality traits are an important aspect when understanding emotion and interpersonal communication. The outcomes of this model are used to help make important predictions on individual behaviors and outcomes. The Big Five personality traits shown in Figure \(\PageIndex{1}\) (and listed following the figure), help us not only to understand our individual experiences and allow us to put into words and categorizations how our emotions interact with our behaviors, but it has also given researchers reliable associations and predictions in life outcomes such as “health, political participation, personal and romantic relationships, purchasing behaviors, and academic and job performances” (Sachl et. al, 2020).
The Big Five Personality Traits
Discussion Questions
- What role of the Big Five personality traits do you see in your communication with others? Do you have significant others with some of these traits?
Culture
Our culture is based on the beliefs, values, and behaviors of a given group, and includes rules and norms that members of the culture follow. The way in which we display, recognize, and interpret emotions is heavily influenced by our social environments and cultural worldview because of their norms and rules (Course Hero, n.d.c). Different cultures have different structures of behavior and therefore different rules regarding how they display their emotions, which are connected to the cultural display rules discussed in Chapter 5. Research has shown that cultures that are more collectivistic, and where social harmony is emphasized, are less likely to showcase negative emotions such as disgust or anger in social settings. In contrast, individualistic cultures, where personal self concept is emphasized, are more likely to showcase emotions of anger or disgust no matter the social context (Dzokoto et. al, 2018). For example, research demonstrated that people from individualistic cultures, like the United States, used exaggerated facial expressions to showcase emotion as a way to influence others and gain attention from those around them, which is accepted within an individualistic culture (University of Minnesota, n.d.). This is opposed to people from collectivistic cultures, such as Japan, where the tendency is to suppress or not show their emotional expressions as a way to observe the social context and interaction between interpersonal relationships. Because collectivistic cultures put the primary concern on the interdependence of the cultural group, emotional displays are direct reflections of the family system and the primary driver is to maintain relationships (University of Minnesota, n.d.).
Understanding emotions in the context of culture is important to making sure we are aware of the ways that differences in communicating emotions may occur. The perception of emotional display rules differs between cultures, where different rules and norms are established and subconsciously understood amongst members. While these elements are rarely spoken about explicitly between cultural group members, they impact the way we interpret and communicate emotions in our relationships. In order to prevent miscommunication within our social relationships, knowing the ways in which a person may express or not express an emotion will allow us to better regulate our own emotional reaction as well.
Social Conventions and Roles
There are many unwritten rules of communication that discourage direct expressions of most emotions. As we said earlier, “being emotional” is largely seen as negative, and our roles in certain contexts are affected. For example, do you curse in the workplace? We attempt to be professional in workplace environments. This includes presenting ourselves as professionals, avoiding unacceptable language for that climate, and preserving face. Face concerns how we present ourselves to others and how we are seen by others. In the workplace, face is an important aspect of the climate. We want to preserve the face of others and avoid face-threatening behaviors (actions that would result in our communication partner losing face). Perhaps you have heard the phrase “saving face” used in this context before. Therefore, there are not only social expectations of us, but we also have processes of self-protection and protection of others.
We have many social and professional roles. How we interact within these roles relates to our environment and our relationships with our communication partners. Gender roles have a lot to do with how we interact with others as well as how we perceive ourselves internally. Keep in mind that biological sex, gender identity, and gender expression are different constructs. Gender identity refers to our internal perception of self, and how we see ourselves. Gender expression refers to how we showcase our gender identity through our appearance, clothing, and verbal and nonverbal expression. These traits relate to how we mask (when, why, and to preserve face) and our reluctance or openness to engage in conversations related to our emotions. Gender expression is also related to the cultural climate we were raised in and our lived experiences.
In a professional setting, we may mask more or avoid dialogue related to emotions, in an attempt to be seen as fulfilling a professional role. In a social setting or role, we may use masking or our decision to engage in discourse related to emotions to promote relational growth. For example, there are certain emotions that may be more often avoided by certain people in the workplace for a variety of reasons. Women, particularly women of color, are less likely to overtly showcase emotions of confidence, assuredness, or even sadness or anger in the workplace so as to not be deemed “too emotional,” because perceptions of assertiveness can turn into aggressiveness or confidence can be misconstrued as arrogance. When we deconstruct how different individuals are or are not “allowed” to experience emotions in different settings, we can start to draw out the stereotypes and biases within our social conventions and society roles.
With the many roles we take on, we utilize these tools to be communication competent. We should beware of emotional labor , the expectation to manage emotions in work environments. Some settings require a lot of masking, which can take a toll on us as individuals and within our interpersonal relationships. If we mask at work all day, we become exhausted. The more we mask or avoid engagement in our emotions, the more we experience emotional labor. Later in this chapter we will discuss identifying our emotions and using reappraisal as a strategy. The capacity to recognize and act on certain emotions decreases without practice.


8.9.4: Data Dive- Aqueducts of Rome
Overview
All drinking water sources are subject to contamination that require appropriate treatment to eliminate disease-causing pathogens. Sources of water contamination can originate from naturally occurring chemicals and minerals (arsenic, radon, uranium), local land use practices (fertilizers, pesticides), manufacturing processes, and sewage. If left untreated, the presence of contaminants in water can lead to adverse health effects, both acute and chronic. This is why the achievement of the aqueducts of Rome are so astounding! Not only did they water to the residents of Rome, but somehow the Romans were able to identify the cleanest water sources for drinking without the most basic testing equipment. In 1995 Peter Aicher published a book titled, “Guide to the aqueducts of ancient Rome.” The book discusses a lot of the history surrounding the 11 aqueducts while also integrating a more modern analysis of the quality of the water based on where it was sourced. The table below provides a brief overview of the aqueducts along with several notes about their use:
Table \(\PageIndex{a}\): Aqueduct characteristics and notes about water volume, source, quality and use. Table by Rachel Schleiger ( CC-BY-NC ) modified from data in Aicher PJ 1995.
| Aqueduct | Construction Complete | Volume (units) | Water Source | Water Quality | Notes |
|---|---|---|---|---|---|
| Appia | 312 BC | 31 | Springs | Good |
All underground except inside walls 70% for civic/imperial uses |
| Anio Vetus | 272-269 BC | 74 | River | Poor | Used for baths, gardens, and industry |
| Marcia | 144-240 BC | 78 | Springs | Best |
Pure/cold/hard water Supplied baths |
| Tepula | 126-125 BC | 7 | Streams | Good | Warm water (60F) |
| Julia | 33 BC | 20 | Springs | Good | N/A |
| Virgo | 22-19 BC | 41 | Marsh | Good |
Almost all underground, some along channel Supplied baths |
| Alsietina | 2 BC | 7 | Lake | Poor | Build to supply basin for mock sea battles |
| Claudia | 38-52 AD | 76 | Springs | Good | Built several branches in the city |
| Anio Novus | 38-52 AD | 78 | River | Okay | Quality was poor until later improved |
| Traiana | 109 AD | 47 | Springs | Good | N/A |
| Alexandria | 226 AD | 9 | Springs | Good | Served baths |
Questions
- How many of the 11 aqueducts do you think have drinkable water?
- Does the above answer surprise you? Why/why not?
- How many of the aqueducts with drinkable water come from a higher volume aqueduct?
- Based on what you can observe in the notes, what did the Romans do when water wasn’t drinkable?
- What is the most surprising thing to you about the data presented in the above table? Why?


5.1: Cosets
Undoubtably, you’ve noticed numerous times that if \(G\) is a group with \(H\leq G\) and \(g\in G\) , then both \(|H|\) and \(|g|\) divide \(|G|\) . The theorem that says this is always the case is called Lagrange’s theorem and we’ll prove it towards the end of this chapter. We begin with a definition.
Let \(G\) be a group and let \(H\leq G\) and \(a\in G\) . The subsets \[aH:=\{ah\mid h\in H\}\] and \[Ha:=\{ha\mid h\in H\}\] are called the left and right cosets of \(H\) containing \(a\) , respectively.
To gain some insight, let’s tinker with an example. Consider the dihedral group \(D_3=\langle r,s\rangle\) and let \(H=\langle s\rangle\leq D_3\) . To compute the right cosets of \(H\) , we need to multiply all of the elements of \(H\) on the right by the elements of \(G\) . We see that \[\begin{aligned} & He =\{ee,se\}=\{e,s\}=H\\ & Hr=\{er,sr\}=\{r,sr\}\\ & Hr^2=\{er^2,sr^2\}=\{r^2,rs\}\\ & Hs=\{es,ss\}=\{s,e\}=H\\ & Hsr=\{esr,ssr\}=\{sr,r\}\\ & Hrs=\{ers,srs\}=\{rs,ssr^2\}=\{rs,r^2\}.\end{aligned}\] Despite the fact that we made six calculations (one for each element in \(D_3\) ), if we scan the list, we see that there are only 3 distinct cosets, namely \[\begin{aligned} & H=He=Hs=\{e,s\}\\ & Hr=Hsr=\{r,sr\}\\ & Hr^2=Hrs=\{r^2,rs\}.\end{aligned}\] We can make a few more observations. First, the resulting cosets formed a partition of \(D_3\) . That is, every element of \(D_3\) appears in exactly one coset. Moreover, all the cosets are the same size—two elements in each coset in this case. Lastly, each coset can be named in multiple ways. In particular, the elements of the coset are exactly the elements of \(D_3\) we multiplied \(H\) by. For example, \(Hr=Hsr\) and the elements of this coset are \(r\) and \(sr\) . Shortly, we will see that these observations hold, in general.
Here is another significant observation we can make. Consider the Cayley diagram for \(D_3\) with generating set \(\{r,s\}\) that is given in Figure \(\PageIndex{1}\). Given this Cayley diagram, we can visualize the subgroup \(H\) and its clones. Moreover, \(H\) and its clones are exactly the 3 right cosets of \(H\) . We’ll see that, in general, the right cosets of a given subgroup are always the subgroup and its clones (see Problem \(\PageIndex{7}\)).
Consider the group \(D_3\) . Find all the left cosets for \(H=\langle s\rangle\) . Are they the same as the right cosets? Are they the same as the subgroup \(H\) and its clones that we can see in the Cayley graph for \(D_3\) with generating set \(\{r,s\}\) ?
As the previous exercise indicates, the collections of left and right cosets may not be the same and when they are not the same, the subgroup and its clones do not coincide with the left cosets.
You might be thinking that somehow right cosets are “better" than left cosets since we were able to visualize them in the Cayley graph. However, this is just a consequence of our convention of composing actions from right to left. If we had adopted a left to right convention, then we would be able to visualize the left cosets in Cayley diagrams.
Computing left and right cosets using a group table is fairly easy. Hopefully, you figured out in Problem \(\PageIndex{1}\) that the left cosets of \(H=\langle s\rangle\) in \(D_3\) are \(H=\{e,s\}\) , \(srH=\{r^2,sr\}\) , and \(rsH=\{r,rs\}\) . Now, consider the following group table for \(D_3\) that has the rows and columns arranged according to the left cosets of \(H\) .
The left coset \(srH\) must appear in the row labeled by \(sr\) and in the columns labeled by the elements of \(H=\{e,s\}\) . We’ve depicted this below.
On the other hand, the right coset \(Hsr\) must appear in the column labeled by \(sr\) and the rows labeled by the elements of \(H=\{e,s\}\) :
As we can see from the tables, \(srH\neq Hsr\) since \(\{sr,r^2\}\neq \{sr,r\}\) . If we color the entire group table for \(D_3\) according to which left coset an element belongs to, we get the following.
We would get a similar table (but in this case, not identical) if we colored the elements according to the right cosets.
Let’s tackle a few more examples.
Consider \(D_3\) and let \(K=\langle r\rangle\) .
- Find all of the left cosets of \(K\) and then find all of the right cosets of \(K\) in \(D_3\) . Any observations?
- Write down the group table for \(D_3\) , but this time arrange the rows and columns according to the left cosets for \(K\) . Color the entire table according to which left coset an element belongs to. Can you visualize the observations you made in part (a)?
Consider \(Q_8\) . Let \(H=\langle i\rangle\) and \(K=\langle -1\rangle\) .
- Find all of the left cosets of \(H\) and all of the right cosets of \(H\) in \(Q_8\) .
- Write down the group table for \(Q_8\) so that rows and columns are arranged according to the left cosets for \(H\) . Color the entire table according to which left coset an element belongs to.
- Find all of the left cosets of \(K\) and all of the right cosets of \(K\) in \(Q_8\) .
- Write down the group table for \(Q_8\) so that rows and columns are arranged according to the left cosets for \(K\) . Color the entire table according to which left coset an element belongs to.
Consider \(S_4\) . Find all of the left cosets and all of the right cosets of \(A_4\) in \(S_4\) . Instead of doing brute-force, try to be clever. Hint: What happens when you compose two even permutations versus an even permutation and an odd permutation?
Consider \(\mathbb{Z}_8\) . Find all of the left cosets and all of the right cosets of \(\langle 4\rangle\) in \(\mathbb{Z}_8\) . Why do you know the left and right cosets are the same without actually verifying?
Consider \((\mathbb{Z},+)\) . Find all of the left cosets and all of the right cosets of \(3\mathbb{Z}\) in \(\mathbb{Z}\) . Why do you know the left and right cosets are the same without actually verifying?
Let \(G\) be a group and let \(H\leq G\) . If \(G\) is abelian, then for all \(a\in G\) , \(aH=Ha\) . That is, if \(G\) is abelian, then the left cosets of \(H\) are the same as the right cosets of \(H\) .
Exercises \(\PageIndex{1}\) and \(\PageIndex{2}\) illustrate that if a group is non-abelian, then the cosets of a subgroup may or may not coincide. That is, knowing that the group is non-abelian is not enough to determine whether the left and right cosets are different.
In all of the examples we’ve seen so far, the left and right cosets partitioned \(G\) into equal-sized chunks. We need to prove that this is true in general. To prove that the cosets form a partition, we will define an appropriate equivalence relation.
Let \(G\) be a group and let \(H\leq G\) . Define \(\sim_L\) and \(\sim_R\) via
\(a\sim_L b\) if and only if \(a^{-1}b\in H\)
and
\(a\sim_R b\) if and only if \(ab^{-1}\in H\) .
Then both \(\sim_L\) and \(\sim_R\) are equivalence relations.*
- *
-
You only need to prove that either \(\sim_L\) or \(\sim_R\) is an equivalence relation as the proof for the other is similar.
Since \(\sim_L\) and \(\sim_R\) are equivalence relations, the corresponding equivalence classes form a partition of \(G\) . If \(a\in G\) , then the “left" and “right" equivalence classes containing \(a\) are given by \[[a]_{\sim_L}=\{g\in G\mid a\sim_L g\}\] and \[[a]_{\sim_R}=\{g\in G\mid a\sim_R g\}.\] The next theorem tells us that the equivalence classes determined by \(\sim_L\) and \(\sim_R\) are indeed the left and right cosets of \(H\leq G\) , respectively.
If \(G\) is a group and \(H\leq G\) , then \([a]_{\sim_L}=aH\) and \([a]_{\sim_R}=Ha\) for all \(a\in G\) .
If \(G\) is a group and \(H\leq G\) , then the left (respectively, right) cosets of \(H\) form a partition of \(G\) .
Next, we argue that all of the cosets have the same size.
Let \(G\) be a group, \(H\leq G\) , and \(a\in G\) . Define \(\phi:H\to aH\) via \(\phi(h)=ah\) . Then \(\phi\) is one-to-one and onto.
Let \(G\) be a group and let \(H\leq G\) . Then all of the left and right cosets of \(H\) are the same size as \(H\) . In other words \(\#(aH)=|H|=\#(Ha)\) for all \(a\in G\) .*
- *
-
As you probably expect, \(\#(aH)\) denotes the size of \(aH\) . Note that everything works out just fine even if \(H\) has infinite order.
The next theorem provides a useful characterization of cosets. Each part can either be proved directly or by appealing to previous results in this section.
Let \(G\) be a group and let \(H\leq G\) .
- If \(a\in G\) , then \(a\in aH\) (respectively, \(Ha\) ).
- We have \(b\in aH\) (respectively, \(Ha\) ) if and only if \(aH=bH\) (respectively, \(Ha=Hb\) ).
- If \(a\in H\) , then \(aH=H=Ha\) .
- If \(a\notin H\) , then for all \(h\in H\) , \(ah\notin H\) (respectively, \(ha \notin H\) ).
The upshot of part (b) of Theorem \(\PageIndex{4}\) is that cosets can have different names. In particular, if \(b\) is an element of the left coset \(aH\) , then we could have just as easily called the coset by the name \(bH\) . In this case, both \(a\) and \(b\) are called coset representatives .
The final result of this section verifies that the clones of a subgroup in a Cayley diagram coincide with the right cosets of the subgroup.
Let \(G\) be a finite group with generating set \(S\) and let \(H\) be a proper subgroup of \(G\) and suppose we can visualize the subgroup for \(H\) in the Cayley diagram for \(G\) using \(S\) as the generating set.
- If \(g\in G\) , verify that the right coset \(Hg\) is a clone of \(H\) . Hint: Suppose \(s\in S\) and \(h_1, h_2\in H\) such that there is an arrow labeled by \(s\) that points from \(h_1\) to \(h_2\) . Argue that there is an arrow labeled by \(s\) pointing from \(h_1g\) to \(h_2g\) .
- If \(C\) is a clone of \(H\) , prove that \(C\) is a right coset of \(H\) .


2.2: Political Economies
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This section explores various ideas connected to the notion of political economies of media. Political economy (PE) is an approach to studying media whose focus is attenuated towards the ways in which media is produced, distributed and consumed, rather than on analysing the interpretations of the signs and symbols found within texts. The combination of the terms ‘political’ and ‘economy’ which make up PE is an explicit reference to the fact that media texts are produced within specific and historically contingent systems which are not merely an ideologically neutral form of exchange, but are conditioned by a range of complex interactions between nation states, international organisations, legal institutions and frameworks, cultural traditions and heritages, other organisations (such as media corporations), technologies, and economic pressures. In other words, PE focuses upon the ways in which politics and economics are not separate entities, as we often encounter them within educational contexts, but that economics and politics are fields which are best understood as being entangled – meaning that they are functionally inseparable – and that understanding elements of this entanglement is pivotal to understanding the way that any society and culture works.


10: Adding to the Conversation with Research Papers Last updated Save as PDF Page ID 20659 Athena Kashyap & Erika Dyquisto City College of San Francisco via ASCCC Open Educational Resources Initiative 10.1: The Purpose of Research Writing This page discusses how research writing is the main platform for academic discourse and conversation. 10.2: The Process of Writing a Research Paper This page explains the overall process of writing a research paper. 10.3: Developing a Research Proposal This page takes a student step by step through developing a research proposal. 10.4: Strategies for Gathering Information This page enumerates various strategies for gathering and evaluating sources. 10.5: Evaluating and Working with Sources This page explains how to evaluate and incorporate your research. 10.6: Reading and Note Taking for Research Papers This page helps you identify themes and organize them to help you begin to organize and develop ideas about your sources. 10.7: Critical Thinking and Research Applications This page expands upon strategies for selecting and synthesizing the information for your research paper. 10.8: Creating a Rough Draft for a Research Paper This page covers drafting your research paper and avoiding some of the pitfalls on a step by step basis. 10.9: Developing a Final Draft of a Research Paper This page covers the specifics editing and finalizing your research paper draft although this is very similar to what you will find on the earlier page on revision. 10.10: Key Takeaways Note Overview of Chapter 5 Thumbnail: pixabay.com/photos/books-lib...rature-768426/


8.5: The Diversity of Today’s Families
The landscape of families has changed considerably over the last few decades. It is not that different types of families have never existed, but in today’s society, we are making places at the table for this diversity. The families that we serve in our early learning centers reflect this.
Types of Families
- Dual parent family
- Single Parent
- Grandparents or other relatives
- Teen parents
- Adoptive families
- Foster families
- Families with same sex parents
- Bi-racial/Multi-racial families
- Families with multi-religious/faith beliefs
- Children with an incarcerated parent(s)
- Unmarried parents who are raising children
- Transgender parents raising children
- Blended families
- Multigenerational Families
- Families formed through reproductive technology
- First time older parents
- Families who are homeless
- Families with children who have developmental delays and disabilities
- Families raising their children in a culture not their own
The list above is extensive; however, other family systems you will encounter in your work with children's families, are all worthy of respect and understanding. For a definition of the types of families listed above, refer to the Appendix.
As an early childhood professional, why might it be important to understand each of these family structures?


8.2: Socialization of Police
It is through socialization that police recruits are inducted into the police subculture, enabling the subculture to maintain its norms and to continue its existence (Newburn and Reiner, 2007; Volti, 2008). Socialization is the process in which recruits are introduced to police officers who impart not only their knowledge but also any negative qualities they possess. The influence of socialization is enormous: it can erase the positive influences from training and introduce the recruit to the darker side of the police subculture (Ellwanger, 2012; Volti, 2008). Ironically, within law enforcement the negative aspects of the socialization of officers are also, at times, positive. Two examples are loyalty and solidarity, which can be both positive and negative. The stories told in police academies may lead to confusion about what is ethical loyalty and solidarity and what is unethical solidarity and loyalty.
Ford (2003) examined this phenomenon in a content analysis study in which he observed the use of parables or stories told by experienced police officers to police recruits during lessons, showing that shifts in the ethics of the recruits resulted from the socialization process that occurs when introducing recruits to the police subculture. To Ford’s surprise, 85% of the parables were neutral about the law and only 11% referred to illegal activities, such as excessive use of force, unconstitutional searches, and lying in court.
Typical of all studies using content analysis, Ford’s (2003) study contains flaws because it relied exclusively on the memory of police recruits. The possibility of poor recollection by police recruits can render the validity of such studies susceptible to bias (Gilbert, 2008). Even police recruits who correctly recall the parables may be mistaken about their intent and may bias their meaning by failing to understand what the instructor was trying to convey (Gilbert, 2008).
Socialization is not just a law enforcement phenomenon. Socialization occurs at all levels of employment, from assembly line workers (Thompson, 2003) to medical students (Becker and Geer, 2003). In most occupations, socialization is a positive influence, as it is a means of learning unwritten rules that help the new worker assimilate into the new work environment (Coffey and Atkinson, 1994; Harper and Lawson, 2003; Volti, 2008). While some occupations possess a strong organizational subculture, which assists new workers beyond their formal training and education, other occupations have little in the way of socialization to help new workers assimilate into the organization (Volti, 2008). However, according to Harper and Lawson (2003), the socialization of all workers is a necessary component for all occupations and professions. Because police exercise a high level of discretion and at times operate outside the realm of rules, the policing occupation relies heavily on socialization to help its recruits (Volti, 2008).
Two primary conditions that Volti (2008) identifies as being associated with higher levels of socialization are occupational isolation and danger. While the policing profession is not statistically dangerous, police officers perceive certain aspects of their job as more dangerous than they are (Banish and Ruiz, 2003; Loyens, 2009; Twersky-Glasner, 2005). Unlike other more dangerous occupations, police officers are subject to acts of willful harm, in which citizens target them intentionally. These dangers are different from those faced by other occupations in which accidents occur. The belief by officers that they are targeted by some citizens who mean them harm reinforces the perceived need to protect one another. The belief in the dangerousness of the police occupation, according to Volti (2008), reinforces the need for socialization in which experienced members of the occupation share information with new recruits that will protect and keep them safe.
Isolation, as identified by Volti (2008), reflects both physical isolation (as with oil rig workers), and social isolation (as with shift workers). Police officers, according to Newburn and Reiner (2008), suffer from isolation based not only on their shift work but also from their subculture, which emphasizes moral conservatism, suspiciousness, and internal solidarity (Naus, van Iterson, and Roe, 2007). Together these make for a potentially toxic level of socialization that police recruits confront when they first start on their journey as police officers. Police officers, as a by-product of their isolation, rely on the solidarity and loyalty of other officers, which may cause increased tension between upholding this solidarity and performing ethically (Reiner, 2010).
Police socialization is particularly invasive early on due to the dominant nature of a police academy’s paramilitary structure (Chappell and Lanza-Kaduce, 2010). Police recruits at the B.C. Police Academy, located at the Justice Institute of British Columbia, are immediately introduced to a formal military-style inspection in their first hour. The nature of paramilitary-style education has historically been to strip a person of his or her individuality and force a culture of compliance upon the individual (Chappell and Lanza-Kaduce, 2010). In doing so, the individual’s personal values are replaced with those of the organization. Chappell and Lanza-Kaduce (2010) further argue that such a pervasive culture should be closely examined, and attempts should be made to neutralize it.
In spite of the negative aspects of socialization, there can be some benefits to the socialization of experienced police officers with junior officers. Paoline (2004) asserts that while socialization within the police subculture is generally negative, there are values that are learned in the process of socialization with senior police officers. Learning the craft of any complex occupation or profession is enhanced when senior members pass on vital information learned from experience (Paoline, 2004). However, it is critical for the recruit to adhere to the organization’s values even if they conflict with information received during negative socialization (Sato, 2003). Socialization can impart to a recruit values and ethics that are not formally written down, yet are needed for the recruit to function well in the job while on the road (Gould and Moore, 2003). A value that recruits learn through socialization is loyalty, which is strongly associated with the military (Loyens, 2009; Sunahara, 2002).
Campbell (2007) further states that the police academy process institutionalizes the culture of the organization in the recruit. This institutionalization is enhanced through the use of artifacts such as wearing uniforms and taking part in drill parades, which are overseen by experienced police officers who ultimately are responsible for enforcing the expectations they have of recruits to adopt the institution’s values and to prove they are suited to continue on the path of a policing career (Campbell, 2007). This is evident at the B.C. Police Academy where police recruits learn how to march and stand for inspection under the watchful eyes of senior officers. The process is designed to ready recruits for ceremonial duties and to learn formations that may be applied in situations such as crowd control.
Ellwanger (2012) agrees that recruits are socialized through these means, but sees a more sinister side to the police subculture, noting that the process of job socialization and enculturation may both purposefully and inadvertently threaten the positive ethical ideals and values brought to the police profession by new recruits. A strong or pervasive deviant subculture, according to Ellwanger (2012), may exist in some instances, which can passively or actively teach unethical behaviours to new police officers.
Chappell and Lanza-Kaduce (2010) add to this concept through their ethnographic study of a police academy in Florida. Here they observed the negative influences of the military nature of the police academy. The attributes of a military-style academy led to periods of socialization in which the recruits were indoctrinated into a paramilitary-style culture whose values included loyalty, solidarity, and dress and deportment (Chappell and Lanza-Kaduce, 2010). The socialization within the walls of the police academy was sufficient as an introduction to police culture; on the road socialization simply reinforces these ideas. Chappell and Lanza-Kaduce (2010) argue that the socialization within the academy is so pervasive that it creates an “us versus them” mentality, which is contrary to values found in community policing. Ellwanger (2012) further suggests that the socialization recruits experience on the job unintentionally thwarts the values and ethical practices they develop at the police academy. The subculture, Ellwanger (2012) argues, is responsible for teaching recruits unethical behaviours.
Additionally, to demonstrate the importance of socialization, Mastrofski and Ritti (1996) investigated the perspective of officers regarding impaired driver investigations. They found that officers trained in impaired driving investigations who returned to supportive organizations were more likely to follow their training. Those officers who returned to organizations that did not value impaired driving investigations eventually considered their training to be “technically irrelevant” (Mastrofski and Ritti, 1996, p.318). The implications of these findings suggest that socialization in a negative organization can undermine positive training.
In taking a different approach, Rokeach et al. (as cited in Twersky-Glasner, 2005) found that socialization plays a secondary role when recruits bring established values into their careers. These personality traits are congruent with those of other experienced police officers, and the socialization process is minor, likely reinforcing recruits’ long-held beliefs. According to Rokeach et al. (as cited in Twersky-Glasner, 2005), these distinctive personality traits are present when the recruit is deciding upon his or her career, and it is these traits that attracts the person to policing.
The socialization of police and other law enforcement officers has both positive and negative components. The negative components create an atmosphere that may lead some officers to immoral and/or unethical conduct that runs contrary to the stated values of the agency. As mentioned previously, citizens who have demonstrated a high level of moral conduct are recruited into policing. Despite demonstrated morality being a key required attribute, a small percentage of officers act immorally on occasion. The socialization of some of these officers may be where they learned their immoral behavior.


12.1A: Overview of Sensation
Sensation refers to our ability to detect or sense the physical qualities of our environment.
- Describe what sensation means in terms of the peripheral nervous system
Key Points
- Sensation refers to our ability to detect and sense the internal and external physical qualities of our environment.
- Our senses include both exteroception (stimuli that occur outside of our body) and interoception (stimuli occurring inside of our bodies).
- Our primary senses are considered to be sight, hearing, taste, smell, and touch.
- All senses require one of four fundamental sensory capacities: chemoreception, photoreception, mechanoreception, or thermoreception.
- The peripheral nervous system (PNS) consists of sensory receptors to communicate with other parts of the body.
Key Terms
- chemoreception : A physiological response to chemical stimuli.
- mechanoreception : A physiological response to mechanical forces like pressure, touch, and vibration.
- photoreception : A physiological response to light, as occurs during vision in animals.
- thermoreception : A physiological response to relative or absolute changes in temperature.
Our senses can be broadly grouped into exteroception, for the detection of stimuli that occur outside of our body, and interoception, for stimuli occurring inside of our bodies. However, what constitutes a sense is a matter of great debate, leading to difficulties in precisely defining what it is. Traditionally, human beings are considered to have five main senses: sight, hearing, taste, smell, and touch.
The peripheral nervous system (PNS) consists of sensory receptors that extend from the central nervous system (CNS) to communicate with other parts of the body. These receptors respond to changes and stimuli in the environment. Sense organs (made up of sensory receptors and other cells ) operate the senses of vision, hearing, equilibrium, smell, and taste.
Sight
Sight or vision (ophthalmoception) is the ability of the eye(s) to focus and detect images of visible light on photoreceptors in the retina that generate electrical nerve impulses for varying colors, hues, and brightness. There are two types of photoreceptors: rods and cones. Rods are very sensitive to light, but do not distinguish colors. Cones distinguish colors, but are less sensitive to dim light. The inability to see is called blindness.
Hearing
Hearing or audition (audioception) is the sense of sound perception. Mechanoreceptors in the inner ear turn vibration motion into electrical nerve pulses. The vibrations are mechanically conducted from the eardrum through a series of tiny bones to hair-like fibers in the inner ear that detect the mechanical motion of the fibers.
Sound can also be detected as vibrations conducted through the body by tactition. The inability to hear is called deafness or hearing impairment.
Taste
Taste (gustaoception) refers to the ability to detect substances such as food, certain minerals, poisons, etc. The sense of taste is often confused with the concept of flavor, which is a combination of taste and smell perception. Flavor depends on odor, texture, and temperature as well as on taste.
Humans receive tastes through sensory organs called taste buds, or gustatory calyculi, concentrated on the upper surface of the tongue. Five basic tastes exist: sweet, bitter, sour, salty, and umami. The inability to taste is called ageusia.
Smell
The olfactory system is the sensory system used for the sense of smell (olfaction). This sense is mediated by specialized sensory cells of the nasal cavity. In humans, olfaction occurs when odorant molecules bind to specific sites on the olfactory receptors in the nasal cavity. These receptors are used to detect the presence of smell. They come together at a structure (the glomerulus) that transmits signals to the olfactory bulb in the brain. The inability to smell is called anosmia.
Touch
Touch or somatosensation (tactioception, tactition, or mechanoreception), is a perception resulting from the activation of neural receptors in the skin, including hair follicles, tongue, throat, and mucosa. A variety of pressure receptors respond to variations in pressure (firm, brushing, sustained, etc.).
The touch sense of itching is caused by insect bites or allergies that involve special itch-specific neurons in the skin and spinal cord. The loss or impairment of the ability to feel anything touched is called tactile anesthesia.
Paresthesia is a sensation of tingling, pricking, or numbness of the skin that may result from nerve damage and may be permanent or temporary.
Additional Senses
Many scientists and philosophers argue that humans have additional senses including:
- Pain or nociception (physiological pain): Signals nerve and other tissue damage.
- Balance or equilibrioception: Allows the sensing of body movement, direction, and acceleration, and to attain and maintain postural equilibrium and balance.
- Body awareness or proprioception: Provides the parietal cortex of the brain with information on the relative positions of the parts of the body.
- Sense of time or chronoception: Refers to how the passage of time is perceived and experienced but is not associated with a specific sensory system. According to psychologists and neuroscientists, however, human brains have a system governing the perception of time.
- Temperature sensing or thermoception: The sensation of heat and the absence of heat (cold).
If interoceptive senses are also considered, sensation can be expanded to include stretch (as in muscles or organs like the lungs), oxygen and carbon dioxide sensing, pH sensing, and more.
While the exact definition of sensation is still controversial, most scientists agree that all senses rely on four fundamental sensory capacities:
- Chemical detection (chemoreception).
- Light detection (photoreception).
- Force detection (mechanoreception).
- Temperature detection (thermoreception).
Our nervous system has sensory systems and organs that mediate each sense and these systems rely on chemoreceptors, photoreceptors, mechanoreceptors, or thermoreceptors to detect the state of the internal or external environment.
The five senses : Photographic depiction of the five senses.


35.3: The Central Nervous System
Skills to Develop
- Identify the spinal cord, cerebral lobes, and other brain areas on a diagram of the brain
- Describe the basic functions of the spinal cord, cerebral lobes, and other brain areas
The central nervous system (CNS) is made up of the brain, a part of which is shown in Figure \(\PageIndex{1}\) and spinal cord and is covered with three layers of protective coverings called meninges (from the Greek word for membrane). The outermost layer is the dura mater (Latin for “hard mother”). As the Latin suggests, the primary function for this thick layer is to protect the brain and spinal cord. The dura mater also contains vein-like structures that carry blood from the brain back to the heart. The middle layer is the web-like arachnoid mater . The last layer is the pia mater (Latin for “soft mother”), which directly contacts and covers the brain and spinal cord like plastic wrap. The space between the arachnoid and pia maters is filled with cerebrospinal fluid (CSF) . CSF is produced by a tissue called choroid plexus in fluid-filled compartments in the CNS called ventricles . The brain floats in CSF, which acts as a cushion and shock absorber and makes the brain neutrally buoyant. CSF also functions to circulate chemical substances throughout the brain and into the spinal cord.
The entire brain contains only about 8.5 tablespoons of CSF, but CSF is constantly produced in the ventricles. This creates a problem when a ventricle is blocked—the CSF builds up and creates swelling and the brain is pushed against the skull. This swelling condition is called hydrocephalus (“water head”) and can cause seizures, cognitive problems, and even death if a shunt is not inserted to remove the fluid and pressure.
Brain
The brain is the part of the central nervous system that is contained in the cranial cavity of the skull. It includes the cerebral cortex, limbic system, basal ganglia, thalamus, hypothalamus, and cerebellum. There are three different ways that a brain can be sectioned in order to view internal structures: a sagittal section cuts the brain left to right, as shown in Figure \(\PageIndex{2}\) b , a coronal section cuts the brain front to back, as shown in Figure \(\PageIndex{2}\) a , and a horizontal section cuts the brain top to bottom.
Cerebral Cortex
The outermost part of the brain is a thick piece of nervous system tissue called the cerebral cortex , which is folded into hills called gyri (singular: gyrus) and valleys called sulci (singular: sulcus).  A thick fiber bundle called the corpus callosum (Latin: “tough body”) connects the two hemispheres and allows information to be passed from one side to the other. Although there are some brain functions that are localized more to one hemisphere than the other, the functions of the two hemispheres are largely redundant. In fact, sometimes (very rarely) an entire hemisphere is removed to treat severe epilepsy. While patients do suffer some deficits following the surgery, they can have surprisingly few problems, especially when the surgery is performed on children who have very immature nervous systems.
In other surgeries to treat severe epilepsy, the corpus callosum is cut instead of removing an entire hemisphere. This causes a condition called split-brain, which gives insights into unique functions of the two hemispheres. For example, when an object is presented to patients’ left visual field, they may be unable to verbally name the object (and may claim to not have seen an object at all). This is because the visual input from the left visual field crosses and enters the right hemisphere and cannot then signal to the speech center, which generally is found in the left side of the brain. Remarkably, if a split-brain patient is asked to pick up a specific object out of a group of objects with the left hand, the patient will be able to do so but will still be unable to vocally identify it.
Link to Learning
See this website to learn more about split-brain patients and to play a game where you can model the split-brain experiments yourself.
Each cortical hemisphere contains regions called lobes that are involved in different functions. Scientists use various techniques to determine what brain areas are involved in different functions: they examine patients who have had injuries or diseases that affect specific areas and see how those areas are related to functional deficits. They also conduct animal studies where they stimulate brain areas and see if there are any behavioral changes. They use a technique called transmagnetic stimulation (TMS) to temporarily deactivate specific parts of the cortex using strong magnets placed outside the head; and they use functional magnetic resonance imaging (fMRI) to look at changes in oxygenated blood flow in particular brain regions that correlate with specific behavioral tasks. These techniques, and others, have given great insight into the functions of different brain regions but have also showed that any given brain area can be involved in more than one behavior or process, and any given behavior or process generally involves neurons in multiple brain areas. That being said, each hemisphere of the mammalian cerebral cortex can be broken down into four functionally and spatially defined lobes: frontal, parietal, temporal, and occipital. Figure \(\PageIndex{3}\) illustrates these four lobes of the human cerebral cortex.
The frontal lobe is located at the front of the brain, over the eyes. This lobe contains the olfactory bulb, which processes smells. The frontal lobe also contains the motor cortex, which is important for planning and implementing movement. Areas within the motor cortex map to different muscle groups, and there is some organization to this map, as shown in Figure \(\PageIndex{4}\). For example, the neurons that control movement of the fingers are next to the neurons that control movement of the hand. Neurons in the frontal lobe also control cognitive functions like maintaining attention, speech, and decision-making. Studies of humans who have damaged their frontal lobes show that parts of this area are involved in personality, socialization, and assessing risk.
The parietal lobe is located at the top of the brain. Neurons in the parietal lobe are involved in speech and also reading. Two of the parietal lobe’s main functions are processing somatosensation —touch sensations like pressure, pain, heat, cold—and processing proprioception —the sense of how parts of the body are oriented in space. The parietal lobe contains a somatosensory map of the body similar to the motor cortex.
The occipital lobe is located at the back of the brain. It is primarily involved in vision—seeing, recognizing, and identifying the visual world.
The temporal lobe is located at the base of the brain by your ears and is primarily involved in processing and interpreting sounds. It also contains the hippocampus (Greek for “seahorse”)—a structure that processes memory formation. The hippocampus is illustrated in Figure \(\PageIndex{6}\). The role of the hippocampus in memory was partially determined by studying one famous epileptic patient, HM, who had both sides of his hippocampus removed in an attempt to cure his epilepsy. His seizures went away, but he could no longer form new memories (although he could remember some facts from before his surgery and could learn new motor tasks).
Evolution Connection: Cerebral Cortex
Compared to other vertebrates, mammals have exceptionally large brains for their body size. An entire alligator’s brain, for example, would fill about one and a half teaspoons. This increase in brain to body size ratio is especially pronounced in apes, whales, and dolphins. While this increase in overall brain size doubtlessly played a role in the evolution of complex behaviors unique to mammals, it does not tell the whole story. Scientists have found a relationship between the relatively high surface area of the cortex and the intelligence and complex social behaviors exhibited by some mammals. This increased surface area is due, in part, to increased folding of the cortical sheet (more sulci and gyri). For example, a rat cortex is very smooth with very few sulci and gyri. Cat and sheep cortices have more sulci and gyri. Chimps, humans, and dolphins have even more.
Basal Ganglia
Interconnected brain areas called the basal ganglia (or basal nuclei ) play important roles in movement control and posture. Damage to the basal ganglia, as in Parkinson’s disease, leads to motor impairments like a shuffling gait when walking. The basal ganglia also regulate motivation. For example, when a wasp sting led to bilateral basal ganglia damage in a 25-year-old businessman, he began to spend all his days in bed and showed no interest in anything or anybody. But when he was externally stimulated—as when someone asked to play a card game with him—he was able to function normally. Interestingly, he and other similar patients do not report feeling bored or frustrated by their state.
Thalamus
The thalamus (Greek for “inner chamber”), illustrated in Figure \(\PageIndex{6}\), acts as a gateway to and from the cortex. It receives sensory and motor inputs from the body and also receives feedback from the cortex. This feedback mechanism can modulate conscious awareness of sensory and motor inputs depending on the attention and arousal state of the animal. The thalamus helps regulate consciousness, arousal, and sleep states. A rare genetic disorder called fatal familial insomnia causes the degeneration of thalamic neurons and glia. This disorder prevents affected patients from being able to sleep, among other symptoms, and is eventually fatal.
Hypothalamus
Below the thalamus is the hypothalamus , shown in Figure \(\PageIndex{6}\). The hypothalamus controls the endocrine system by sending signals to the pituitary gland, a pea-sized endocrine gland that releases several different hormones that affect other glands as well as other cells. This relationship means that the hypothalamus regulates important behaviors that are controlled by these hormones. The hypothalamus is the body’s thermostat—it makes sure key functions like food and water intake, energy expenditure, and body temperature are kept at appropriate levels. Neurons within the hypothalamus also regulate circadian rhythms, sometimes called sleep cycles.
Limbic System
The limbic system is a connected set of structures that regulates emotion, as well as behaviors related to fear and motivation. It plays a role in memory formation and includes parts of the thalamus and hypothalamus as well as the hippocampus. One important structure within the limbic system is a temporal lobe structure called the amygdala (Greek for “almond”), illustrated in Figure \(\PageIndex{6}\). The two amygdala are important both for the sensation of fear and for recognizing fearful faces. The cingulate gyrus helps regulate emotions and pain.
Cerebellum
The cerebellum (Latin for “little brain”), shown in Figure \(\PageIndex{3}\), sits at the base of the brain on top of the brainstem. The cerebellum controls balance and aids in coordinating movement and learning new motor tasks.
Brainstem
The brainstem , illustrated in Figure \(\PageIndex{3}\), connects the rest of the brain with the spinal cord. It consists of the midbrain, medulla oblongata, and the pons. Motor and sensory neurons extend through the brainstem allowing for the relay of signals between the brain and spinal cord. Ascending neural pathways cross in this section of the brain allowing the left hemisphere of the cerebrum to control the right side of the body and vice versa. The brainstem coordinates motor control signals sent from the brain to the body. The brainstem controls several important functions of the body including alertness, arousal, breathing, blood pressure, digestion, heart rate, swallowing, walking, and sensory and motor information integration.
Spinal Cord
Connecting to the brainstem and extending down the body through the spinal column is the spinal cord , shown in Figure \(\PageIndex{3}\). The spinal cord is a thick bundle of nerve tissue that carries information about the body to the brain and from the brain to the body. The spinal cord is contained within the bones of the vertebrate column but is able to communicate signals to and from the body through its connections with spinal nerves (part of the peripheral nervous system).  Myelinated axons make up the “white matter” and neuron and glial cell bodies make up the “gray matter.” Gray matter is also composed of interneurons, which connect two neurons each located in different parts of the body. Axons and cell bodies in the dorsal (facing the back of the animal) spinal cord convey mostly sensory information from the body to the brain. Axons and cell bodies in the ventral (facing the front of the animal) spinal cord primarily transmit signals controlling movement from the brain to the body.
The spinal cord also controls motor reflexes. These reflexes are quick, unconscious movements—like automatically removing a hand from a hot object. Reflexes are so fast because they involve local synaptic connections. For example, the knee reflex that a doctor tests during a routine physical is controlled by a single synapse between a sensory neuron and a motor neuron. While a reflex may only require the involvement of one or two synapses, synapses with interneurons in the spinal column transmit information to the brain to convey what happened (the knee jerked, or the hand was hot).
In the United States, there around 10,000 spinal cord injuries each year. Because the spinal cord is the information superhighway connecting the brain with the body, damage to the spinal cord can lead to paralysis. The extent of the paralysis depends on the location of the injury along the spinal cord and whether the spinal cord was completely severed. For example, if the spinal cord is damaged at the level of the neck, it can cause paralysis from the neck down, whereas damage to the spinal column further down may limit paralysis to the legs. Spinal cord injuries are notoriously difficult to treat because spinal nerves do not regenerate, although ongoing research suggests that stem cell transplants may be able to act as a bridge to reconnect severed nerves. Researchers are also looking at ways to prevent the inflammation that worsens nerve damage after injury. One such treatment is to pump the body with cold saline to induce hypothermia. This cooling can prevent swelling and other processes that are thought to worsen spinal cord injuries.
Summary
The vertebrate central nervous system contains the brain and the spinal cord, which are covered and protected by three meninges. The brain contains structurally and functionally defined regions. In mammals, these include the cortex (which can be broken down into four primary functional lobes: frontal, temporal, occipital, and parietal), basal ganglia, thalamus, hypothalamus, limbic system, cerebellum, and brainstem—although structures in some of these designations overlap. While functions may be primarily localized to one structure in the brain, most complex functions, like language and sleep, involve neurons in multiple brain regions. The spinal cord is the information superhighway that connects the brain with the rest of the body through its connections with peripheral nerves. It transmits sensory and motor input and also controls motor reflexes.
Glossary
- amygdala
- structure within the limbic system that processes fear
- arachnoid mater
- spiderweb-like middle layer of the meninges that cover the central nervous system
- basal ganglia
- interconnected collections of cells in the brain that are involved in movement and motivation; also known as basal nuclei
- basal nuclei
- see basal ganglia
- brainstem
- portion of the brain that connects with the spinal cord; controls basic nervous system functions like breathing, heart rate, and swallowing
- cerebellum
- brain structure involved in posture, motor coordination, and learning new motor actions
- cerebral cortex
- outermost sheet of brain tissue; involved in many higher-order functions
- choroid plexus
- spongy tissue within ventricles that produces cerebrospinal fluid
- cingulate gyrus
- helps regulate emotions and pain; thought to directly drive the body’s conscious response to unpleasant experiences
- corpus callosum
- thick fiber bundle that connects the cerebral hemispheres
- cerebrospinal fluid (CSF)
- clear liquid that surrounds the brain and spinal cord and fills the ventricles and central canal; acts as a shock absorber and circulates material throughout the brain and spinal cord.
- dura mater
- tough outermost layer that covers the central nervous system
- frontal lobe
- part of the cerebral cortex that contains the motor cortex and areas involved in planning, attention, and language
- gyrus
- (plural: gyri) ridged protrusions in the cortex
- hippocampus
- brain structure in the temporal lobe involved in processing memories
- hypothalamus
- brain structure that controls hormone release and body homeostasis
- limbic system
- connected brain areas that process emotion and motivation
- meninge
- membrane that covers and protects the central nervous system
- occipital lobe
- part of the cerebral cortex that contains visual cortex and processes visual stimuli
- parietal lobe
- part of the cerebral cortex involved in processing touch and the sense of the body in space
- pia mater
- thin membrane layer directly covering the brain and spinal cord
- proprioception
- sense about how parts of the body are oriented in space
- somatosensation
- sense of touch
- spinal cord
- thick fiber bundle that connects the brain with peripheral nerves; transmits sensory and motor information; contains neurons that control motor reflexes
- sulcus
- (plural: sulci) indents or “valleys” in the cortex
- temporal lobe
- part of the cerebral cortex that processes auditory input; parts of the temporal lobe are involved in speech, memory, and emotion processing
- thalamus
- brain area that relays sensory information to the cortex
- ventricle
- cavity within brain that contains cerebrospinal fluid


1.1: Passion
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Dave Dillon
“Ganas. That’s all you need. The desire to learn.”
– Jaime Escalante
Think about what you are passionate about. It might be family, friends, a significant other, a pet, an upcoming vacation, or what you might have for dinner. Different people are passionate about different things. Ask yourself: Why are you passionate about those things? What makes you passionate about them? Now ask yourself if you are passionate about school.
Author’s Story
I can think of many things I would rather do than sit in a classroom listening to a lecture. I’d rather be relaxing at the beach, traveling to a new place, or playing Mario Kart with my family and friends. But when I was in college, my education was extremely important to me. I had a tremendous amount of passion, which allowed me to succeed. I had the attitude that nothing was going to stand in the way of getting my degree. In my first year in college I took an Introduction to Sociology class that genuinely interested me. It was easy to be passionate about it because I really liked the subject matter, my professor, and the textbook. I also took Microeconomics. And while I understood its value and importance, I was not as interested in attending and completing the assignments. However, I always knew I needed to find passion in the course if I wanted to be successful and accomplish my goals. One strategy that worked for me was to find situations where I could apply concepts in those less interesting classes to my personal life. For instance, if the lecture and textbook were explaining a Microeconomics concept like total and marginal utility, I would try to apply this to something I could easily relate to. If utility is the satisfaction of the consumption of a product for a consumer, I would think of an example involving Arby’s roast beef sandwiches, and blue raspberry slurpees. Making the material meaningful to me allowed me to be passionate about learning something I otherwise would not have been.
“Brick walls are there for a reason: they let us prove how badly we want things.”
– Randy Pausch
There were other activities I enjoyed more than class, but I knew it was important to find a passion for my classes because it was the key to succeeding in them.
It is common to have other things you would like to do more than sitting in class, doing homework and preparing for exams. But you still must have passion for the learning and for the class in order to be successful.
My favorite definition of success is from John Wooden: “Success is peace of mind which is a direct result of self-satisfaction in knowing you did your best to become the best you are capable of becoming.”
Why Are You Here?
Please note: It is OK to not know what your goal is when you start college. In fact, it is extremely common for students not to know what their goal is or what their major is when they begin college, but there is value in identifying your goal(s) as soon as possible.
More questions to ask yourself: Why are you in college, and why are you taking the courses you’re taking? If you can answer these questions with solid logic and understand their purpose and how they fit in to being important to your life, you are off to a great start. However, if you are taking classes at someone else’s suggestion and you are not genuinely interested in them, you may want to reconsider. I do not wish it to be misconstrued that I recommend you drop out of college, rather I want you to have a plan and passion to be able to achieve your goals. For many people, higher education is a necessary part of their goals.
I see many students in my counseling office who want to be independent, work a full time job, and/or party (rather than go to college). I also see many students who come back a few years later with a renewed passion and value for their education.
For college success, you must attend when the time is right for you. How do you know if it’s the right time? Ask yourself if it’s the right time for the following students to go to college:
- Monica’s goal is to go to a university. She was accepted but couldn’t afford it. She enrolls at a community college. She is passionate about attending community college and then transferring to earn a bachelor’s degree.
- Christina is a high school graduate. She would like to take a year off of school to work and travel. Her parents gave her an ultimatum, saying that if she wanted to continue to live at home, she had to go to college full-time.
- Javier completed one year of college then got married in his early 20s. He and his spouse raised four children and he has been working for 20 years in an uninteresting, low-paying job. He always wanted to finish college and now finally has the time to go back to school.
- Andy is interested in partying and little else. He knows his college education is important but it is a low priority at this point.
Intrinsic vs. Extrinsic Passion
Sometimes we are motivated by a specific desired outcome of performing a task. Some people play a game because they want to win. In education, some students work hard because they want to receive a good grade or transfer to a prestigious university. Parents of younger children may give a monetary reward for each “A” their student earns. This is extrinsic motivation.
Interest, desire to learn, and enjoyment of a subject are characteristics of intrinsic motivation, or what we call passion. Passion for your education must come from within. If your educational goals (passing a college course, acquiring new skills or attaining a degree) are important enough to you, your motivation can become intrinsic, allowing you to find passion, which will help you reach your goals. Without passion, you may find yourself struggling, withdrawing from courses, earning poor grades, or dropping out. External rewards of ascending to a certain academic level or acquiring wealth, lose some of their appeal if students do not find the work to get there personally rewarding. These students, who truly embrace their work, are intrinsically motivated – passionate while those who are focused mainly on rewards for high achievement and punishment for poor performance are extrinsically motivated. Trophies, medals, money, new clothes or a new car are examples of extrinsic motivators. One could argue, “the end justifies the means”—that it doesn’t matter if a students’ passion comes internally or externally, as long as they accomplish their goals. However, when the reward is learning itself, the student is on road to long-term success!
“Only passions, great passions, can elevate the soul to great things.”
– Denis Diderot
The Choice Is Yours
I believe one of the best decisions you can make is to attend college if you are passionate about it and it is the right time for you. On the other hand it is better to postpone attending college if you are not passionate about it or feel the time is not right. Please do not misunderstand – I am not discouraging anyone from going to college nor am I encouraging anyone to drop out of college. And I do not expect you to be passionate about every aspect of college. There were some classes and some requirements that I disliked during my own college experience. My concern, however, is students who start college and are not passionate about it. After a few years and a poor transcript, they meet with a counselor saying they weren’t in college for the right reasons, weren’t serious about their education, didn’t know what they were doing, or… “my parents made me go.” There are some suggestions in this book that can assist a passionate student to succeed. But all of the suggestions in the world will not help a student lacking passion.
“Nothing great in the world has ever been accomplished without passion.”
– Hebbel
There is a scene from the movie Serendipity where Dean’s character says, “You know the Greeks didn’t write obituaries. They only asked one question after a man died: ‘Did he have passion?’” I will leave it up to you to decide if this is true or if it is Hollywood taking a liberty, but either way that quote has stayed with me. You can be successful in college. This textbook is a journey in figuring out how you are going to get there.
Licenses and Attributions:
Content previously copyrighted, published in Blueprint for Success in College: Indispensable Study Skills and Time Management Strategies (by Dave Dillon). Now licensed as CC BY: Attribution.


27.3A: Trophoblast Development
Trophoblasts are the outer layer of cells that provide nutrients to the embryo and form part of the placenta.
- Describe the trophoblast
Key Points
- The trophoblast is subdivided into two layers, the inner cytotrophoblast, which proliferates upon implantation, and the outer syncytiotrophoblast, which supports cytotrophoblast proliferation through contact with the maternal blood.
- The cytotrophoblast, at the edges of the villi in the placenta, further differentiates into extravillous trophoblasts, which penetrate into the uterus and attach to the placenta and the mother to promote placental vasculature.
- Some trophoblasts replace endothelial cells in the uterine spiral arteries and remodel them into wide-bore conduits that are independent of maternal vasoconstriction. This ensures the fetus receives a steady supply of blood, and that the placenta is not sensitive to damaging fluctuations in oxygen.
Key Terms
- decidualization : The changes in the endometrial lining after ovulation, characterized by its transformation into a secretory lining in preparation to accept an embryo.
- extravillous trophoblast : These grow out from the placenta and penetrate into the decidualized uterus.
- trophoblast : The membrane of cells that forms the wall of a blastocyst during early pregnancy, and also provides nutrients to the embryo and later develops into part of the placenta.
Trophoblasts
Trophoblasts (from the Greek words trephein, to feed, and blastos, germinator) are cells that form the outer layer of a blastocyst. These cells provide nutrients to the embryo and develop into a large part of the placenta.
They are formed during the first stage of pregnancy and are the first cells to differentiate from the fertilized egg. This layer of trophoblasts is also collectively referred to as the trophoblast, or, after gastrulation, the trophectoderm, as it is then contiguous with the ectoderm of the embryo.
Trophoblast Function
Trophoblasts play an important role in embryo implantation and interaction with the endometrium of the maternal uterus following decidualization. The trophoblast is composed of two layers: an inner cytotrophoblast and an outer syncytiotrophoblast.
The syncytiotrophoblast is non-proliferative and thus relies on fusion of the underlying cytotrophoblast cells to expand. The syncytiotrophoblast are the cells in direct contact with the maternal blood that reaches the placental surface, and thus facilitates the exchange of nutrients, wastes, and gases between the maternal and fetal systems.
Cytotrophoblast in the tips of villi can differentiate into another type of trophoblast called the extravillous trophoblast. Extravillous trophoblasts grow out from the placenta and penetrate into the decidualized uterus.
This process is essential not only for physically attaching the placenta to the mother, but also for altering the vasculature in the uterus to allow it to provide an adequate blood supply to the growing fetus as pregnancy progresses.
Some of the trophoblast even replaces the endothelial cells in the uterine spiral arteries as they remodel these vessels into wide bore conduits that are independent of maternal vasoconstriction. This ensures the fetus receives a steady supply of blood, and the placenta is not sensitive to fluctuations in oxygen that could cause it damage.
Extraembryonic coelom or chorionic cavitiy : A blastocyst embedded in the uterine decidua. (am. Amniotic cavity, b.c. Blood clot., b.s. Body stalk., etc Embryonic ectoderm, ent. Entoderm., mes. Mesoderm, m.v. Maternal vessels., tr. Trophoblast., u.e. Uterine epithelium, u.g. Uterine glands., y.s. Yolk-sac.)
Clinical Example
Intrauterine growth restriction (IUGR) can result in an undersized fetus with poor organ development or even death. The primary factor in IUGR is placental dysfunction caused by a failure of the extravillous trophoblasts to penetrate and modify the uterine spiral arteries. The result is a poorly-oxygenated environment and reduced fetal growth.


1.6: Review Questions
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1.
Which activity would the nurse perform when engaged in population health activities?
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Treating an individual for a specific disease
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Improving health outcomes for groups of people
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Evaluating a family’s ability to care for a child with diabetes
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Teaching a client health promotion behaviors
2.
Which method would the nurse utilize when taking an individual-level approach to smoking cessation?
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Forming a smoking cessation support group
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Promoting an increase on taxes on the purchase of tobacco
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Providing nicotine gum to a client to substitute for an inhaled tobacco product
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Researching the reasons for initiation of tobacco use
3.
Which central tenet of population health should the nurse include when planning population health priorities?
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Proactively promoting health among populations
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Reactively managing health conditions
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Treating diseases in individual people
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Focusing on increasing the number of hospitals
4.
Which action by the nurse represents a midstream approach to improving population health outcomes?
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Advocating for policy changes regarding fast food
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Providing a workplace lunchtime walking program
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Encouraging a client to lose weight
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Starting a support group for smoking cessation
5.
Which action by the nurse promotes population health?
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Providing treatment for chronic disease
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Conducting health education workshops
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Offering individual health consultations
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Administering medication for acute illnesses
6.
Which data should the nurse utilize to determine the leading cause of death across the population?
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Infant mortality
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Life expectancy
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Morbidity rate
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General mortality
7.
Which potential barrier of siloed health care should the nurse consider when planning health promotion activities?
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Providers and specialists working closely together to improve outcomes
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Treating one disease at a time without evaluating or addressing the full picture of health
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Health systems becoming effectively integrated
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An emphasis on population health and health promotion
8.
Which action is a characteristic of population-based nursing practice?
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Taking a proactive approach to promoting wellness and preventing disease
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Emphasizing curative care rather than preventive care
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Focusing on reactive approaches to managing acute illnesses
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Providing care only outside of hospital settings
9.
Which concept should the nurse utilize when planning transitional care for a population?
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Providing care in multiple areas of the care continuum to address all client needs
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Reactively managing health conditions during transitions between health care sites
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Preventing hospital readmissions and adverse events
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Coordinating clients as they move between care settings
10.
Which health service along the health care continuum would the nurse utilize for a client with health care needs related to a chronic condition?
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A preventive health program
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An ambulatory care clinic
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An acute care department
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A long-term care facility