29 Apr questions are in the file, couple of them are not multiple choice. answers can be found in the book ‘Recipes for Science’ , but the writer

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Section I: Scientific Reasoning Using Experiments (34 points total)

BACKGROUND: Soylent* is a liquid meal product (like a smoothie or an energy drink) that is available in the United States. This product meets all nutritional requirements for an average adult, thereby allowing it to be the only source of food/drink that one needs. Upon creating the product, inventor Rob Rhinehart consumed nothing but Soylent for 30 days. During this time, he assessed his overall health. After measuring the results, Rhinehart reported that his energy levels skyrocketed, his skin improved, he had prolonged mental concentration, he was less fatigued, and he was able to run farther than he ever had.

* Yes, this is a real product. It is named after a drink from the 1966 science fiction novel Make Room! Make Room!. The novel was the basis for the 1973 sci-fi film Soylent Green.

Suppose you are a researcher who wants to investigate whether one of Rhinehart's claims about the effects of Soylent is indeed true. The questions in this section will guide you in designing an experimental study. All short answer questions in this section should be answered with no more than 3 sentences.

 

Flag question: Question 1

Question 12 pts

What is your hypothesis?

Flag question: Question 2

Question 24 pts

What would you expect to see if your hypothesis is true? What would you expect to see if your hypothesis is false?

Flag question: Question 3

Question 32 pts

An independent variable is:

Group of answer choices

A variable whose value varies as a result of a change to another variable

A variable whose value varies as a result of purposeful intervention

A variable that is not manipulated by researchers but affects the values of other variables nonetheless

A variable that counteracts the influence of other variables

 

Flag question: Question 4

Question 42 pts

What is the independent variable in your experiment?

Flag question: Question 5

Question 52 pts

A dependent variable is:

Group of answer choices

A variable whose value varies as a result of a change to another variable

A variable whose value varies as a result of purposeful intervention

A variable that is not manipulated by researchers but affects the values of other variables nonetheless

A variable that counteracts the influence of other variables

 

Flag question: Question 6

Question 62 pts

What is the dependent variable in your experiment?

Flag question: Question 7

Question 72 pts

Why is identifying background conditions/extraneous variables important?

 

Flag question: Question 8

Question 82 pts

Briefly state what you will be doing in your experiment. Make sure to identify who your subjects are and what will they be doing.

 

Flag question: Question 9

Question 92 pts

What observations will you make in your experiment? In other words, what data will you collect?

 

Flag question: Question 10

Question 103 pts

What is one legitimate value that you bring to this experiment?

Flag question: Question 11

Question 113 pts

What is one illegitimate value or bias that you need to protect against?

Flag question: Question 12

Question 124 pts

No experiment is perfect. What is one trade-off or choice this experiment makes that renders it less than perfect? (Think about the variables, sample size, or group assignment). Explain why this is important.

Flag question: Question 13

Question 134 pts

Sometimes there are sources of uncertainty that can make it challenging to draw conclusions from experiments. What is one source of uncertainty that you may want to flag when drawing a conclusion? Explain why this is important.

 

Flag question: Question 14

Question 140 pts

What is Soylent Green made from?*

*Note: This question is a joke about the movie. It is worth zero points.

 

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Section II: Scientific Reasoning Using Models (44 points total)

This section consists of three parts. Each part begins with a description of a scientific experiment. Read each description and answer the questions that follow it. All questions should be answered with no more than 3 sentences unless specified otherwise.

 

Flag question: Spacer

Section II: Part 1

BACKGROUND: A galaxy is a system of stars, gas, and dust that is held together by gravitational attraction. Most galaxies have spiral or elliptical shapes, but not all of them do. Galaxies that are neither spiral nor elliptical are often referred to as peculiar galaxies. One kind of peculiar galaxy is a ring galaxy. Galaxies of this shape are rather rare, and astronomers want to figure out how they got their shape. One possibility is that a ring galaxy was at one point a spiral galaxy that collided with another galaxy–its companion galaxy–and as a result of this collision, the spiral galaxy somehow transformed into a ring galaxy.

  

 

Flag question: Question 15

Question 151 pts

What is the astronomers’ research question? 

 

Flag question: Question 16

Question 161 pts

What is the hypothesis under investigation? 

Flag question: Spacer

Section II: Part 2

BACKGROUND: The astronomers decide to investigate these ring galaxies by building computer simulations. In order to build their computer simulations, the astronomers must first observe a handful of ring galaxies. Through their observations, the astronomers notice that some ring galaxies have a high concentration of stars in their rings while other ring galaxies have a low concentration of stars in their rings. By observing a galaxy and its companion, astronomers can determine the radial velocity (rotation speed) of each galaxy, the speed at which each galaxy is currently moving, and the current mass of each galaxy. In their computer simulations, the astronomers let point particles stand in for the stars, gas, and dust that make up the mass of a galaxy. As they run the simulations, the astronomers systematically vary the concentration of stars, the masses of the two galaxies, and the angle at which the companion strikes the galaxy.

 

Flag question: Question 17

Question 172 pts

Identify the astronomers' target system.

 

Flag question: Question 18

Question 184 pts

Identify two things about the target system that the astronomers idealized or made an approximation about when constructing their simulations, and explain why the astronomers needed to make those idealizations or approximations.

 

Flag question: Question 19

Question 194 pts

How does the astronomers' computer simulation represent the target system?

 

Flag question: Question 20

Question 206 pts

Do you think the astronomers developed a good model? Why or why not? (Hint: Explain your reasoning by appealing to considerations of accuracy, generality, precision, tractability, and robustness).

Note: This question should be answered in at least 4 but no more than 6 sentences.

Flag question: Spacer

Section II: Part 3

By running the simulations thousands of times and varying the parameters, the astronomers discover that the only way for these ring galaxies to get this shape is through a collision with another galaxy. However, the ring galaxy only occurs under very specific conditions: when the collision is slightly off centered, and when the galaxies are very small (~1.3×10 10 M⊙). They also learned about the timescales over which these ring galaxies “live” (which is not very long! They dissipate after only 100 million years).

 

Flag question: Question 21

Question 214 pts

You now have enough information to provide a scientific argument for a scientific conclusion about ring galaxies. Write the argument in standard form.

 

Flag question: Question 22

Question 221 pts

What kind of inference is made in this argument?

 

Flag question: Question 23

Question 234 pts

Are the astronomers confirming their hypothesis, refuting their hypothesis, or neither? Explain your answer.

 

Flag question: Question 24

Question 244 pts

What kind of explanation have the astronomers offered for these ring galaxies shapes, and why is it that kind of explanation?

 

Flag question: Question 25

Question 254 pts

If the astronomers wanted to develop a better model with the aim of improving the support for, and confidence in their conclusion, what do you think they could improve upon? Why would this be useful?

 

Flag question: Question 26

Question 263 pts

Our book has focused on three important steps (or ingredients) present in a scientific investigation that allows for the production of scientific knowledge. Explain how the following ingredient is present in this ring galaxy case study:

 

Ingredient 1: Hypotheses are used to generate expectations

 

Flag question: Question 27

Question 273 pts

Our book has focused on three important steps (or ingredients) present in a scientific investigation that allows for the production of scientific knowledge. Explain how the following ingredient is present in this ring galaxy case study:

 

Ingredient 2: Expectations are compared to observations

 

Flag question: Question 28

Question 283 pts

Our book has focused on three important steps (or ingredients) present in a scientific investigation that allows for the production of scientific knowledge. Explain how the following ingredient is present in this ring galaxy case study:

 

Ingredient 3: Post-comparison is used to develop, confirm, reject, or refine a hypothesis

 

Flag question: Spacer

Section III: Quantitative (Probabilistic and Statistical) Reasoning in Everyday Science (24 points total)

All your hard work in How Science Works has paid off! You landed yourself an undergraduate clinic research assistant job in the UC Health System. During your first day, you shadow 3 different teams to decide which you would like to work with.

 

Flag question: Question 29

Question 292 pts

You first shadow a nurse practitioner (NP) talking to a couple about their recent genetics screening. The NP tells a couple that their genetic makeup means that they have a one in four chances of having a child with an inherited illness.

 

Does this mean that if their first child has the illness, the next three will not?

Group of answer choices

Yes

No

 

Flag question: Question 30

Question 302 pts

You first shadow a nurse practitioner (NP) talking to a couple about their recent genetics screening. The NP tells a couple that their genetic makeup means that they have a one in four chances of having a child with an inherited illness.

 

Does this mean that each of the couple’s children will have the same risk of suffering from the illness? 

Group of answer choices

Yes

No

 

Flag question: Question 31

Question 312 pts

During the consultant with a second couple, the NP discusses the likelihood their children might be carriers of Gene W or Gene Q (which are mutually exclusive). Suppose the probabilities of having a child with these Gene W or Gene Q are the same—both are 50%.

 

What is the probability that the couple has two children with Gene W?

 

Flag question: Question 32

Question 322 pts

During the consultant with a second couple, the NP discusses the likelihood their children might be carriers of Gene W or Gene Q (which are mutually exclusive). Suppose the probabilities of having a child with these Gene W or Gene Q are the same—both are 50%.

 

At least one of the children has Gene W. What is the probability that the couple has two children with Gene W?

 

Flag question: Question 33

Question 332 pts

During the consultant with a second couple, the NP discusses the likelihood their children might be carriers of Gene W or Gene Q (which are mutually exclusive). Suppose the probabilities of having a child with these Gene W or Gene Q are the same—both are 50%.

 

The eldest of the two children has Gene Q. Given this, what is the probability that the couple has two children with Gene Q?

 

Flag question: Question 34

Question 344 pts

After shadowing the NP, your next shadow activity is to attend your a research lab meeting.

Your lab has two research interns present and discuss the best way to test whether a certain drug is effective against high blood pressure. The first research intern wants to give the drug to 1,000 people with high blood pressure and see how many of them experience lower blood pressure levels. The second research intern wants to give the drug to 500 people with high blood pressure and not give the drug to another 500 people with high blood pressure, and see how many in both groups experience lower blood pressure levels. One of the interns has designed a better study than the other.

 

Which intern has the better way to test this drug, and why?

 

Flag question: Question 35

Question 352 pts

One of the lab’s recent studies examined 323 healthy women who wore a AppleWatch that tracked their sleep each night. The women with sleep problems (difficultly falling asleep and waking up throughout the night) were significantly more likely to have high blood pressure than women without those sleep problems.

 

Which of the following is correct?

Group of answer choices

Higher blood pressure caused the women to have sleep problems.

Any woman in this study with sleep problems also had high blood pressure.

For any two women in this study, the one who has more sleep problems has higher blood pressure.

There was an association between sleep problems and high blood pressure, but it's not necessarily a causal relationship.

 

Flag question: Question 36

Question 362 pts

Your research team conducted two different runs of the same experiment. When comparing the two data sets A and B, you notice that they both have the same mean, but data set A has a higher standard deviation.

 

What can you conclude about the difference between the two data sets?

 

Flag question: Question 37

Question 374 pts

Your last shadow experience involves assisting in the cancer wing. This research group did a study asking 2,000 patents to submit responses to a questionnaire by mail. They received 450 responses. They found that the mean survival rate for respondents was 10 years after diagnosis. The researchers concludes that with this diagnosis the average survival rate is 10 years.

 

Is this a reasonable inference?  Why or why not? 

 

Flag question: Question 38

Question 382 pts

The patient you are assisting has a lump in her breast and must have a mammogram. Of 100 women like her, 10 of them actually have a malignant (cancerous) tumor, and 90 of them do not. Of the 10 women who actually have a tumor, the mammogram indicates correctly that 9 of them have a tumor and indicates incorrectly that 1 of them does not have a tumor. Of the 90 women who do not have a tumor, the mammogram indicates correctly that 80 of them do not have a tumor and indicates incorrectly that 10 of them do have a tumor. The table below summarizes all of this information:

	Tested Positive	Tested Negative	Totals
Actually has a cancerous tumor.	9 persons	1 person	10 people
Does not have a cancerous tumor.	10 persons	80 persons	90 people
Totals:	19 persons	81 persons	100 people

 

Imagine that your patient tests positive (as if she had a tumor), what is the likelihood that she actually has a tumor?   out of 

 

Flag question: Spacer

Section IV: Theories, Values, and Society (10 points total)

 

 

Flag question: Question 39

Question 395 pts

What is the value-free ideal of science? Why is the value-free ideal of science problematic? 

Flag question: Question 40

Question 405 pts

What is the difference between a theory and a hypothesis?