Question 1

The temperature at which an alligator's egg is incubated will determine the sex of the offspring. The dependent and the independent variables in this experiment are ________.

Accepted Answer

The answer of The temperature at which an alligator's egg...

Question 2

Cotton-topped tamarins are small primates with tufts of long white hair on their heads. While studying these creatures, you notice that males with longer hair get more opportunities to mate and father more offspring. To test the hypothesis that having longer hair is adaptive in these males, you should ________.

Accepted Answer

To test the hypothesis that having longer hair is adaptive in these males, it is necessary to determine if hair length is heritable. This would involve measuring hair length in related individuals and determining the degree of similarity. Testing other traits or examining hair in ancestors would not necessarily provide relevant information, and testing shaved males would not test the adaptive value of hair length.

Question 3

Agrobacterium infects plants and causes them to form tumors. You are asked to determine how long a plant must be exposed to these bacteria to become infected. Which of the following experiments will provide the best data to address that question?

Accepted Answer

To determine how long a plant must be exposed to Agrobacterium to become infected, the best experiment would be to measure the number of tumors formed on plants that are exposed to Agrobacterium for different lengths of time. This would allow for the determination of the minimum amount of time required for the plant to become infected. The other options do not directly address the question of how long exposure is required for infection.

Question 4

Which of the following questions is considered a thought-provoking scientific query?

Accepted Answer

The answer of Which of the following questions is considered...

Question 5

Agrobacterium infects plants and causes them to form tumors. You determine that tumor formation requires a large amount of the plant's energy for tissue formation. How might this change the number of offspring a plant produces, and what is the most likely explanation for this change?

Accepted Answer

The formation of tumors requires a large amount of the plant's energy for tissue formation, which means that the plant will divert energy away from reproduction. This suggests that the number of offspring produced by the plant will decrease.

Question 6

In presenting data that result from an experiment, a group of students show that most of their measurements fall on a straight diagonal line on their graph. However, two of their data points are "outliers" and fall far to one side of the expected relationship. What should they do?

Accepted Answer

It is important to show all results obtained, including outliers, as they may provide important information for understanding the experiment. The students should explore the reasons for the outliers, such as potential errors in measurement or sample contamination. Simply ignoring or changing the outliers could lead to false conclusions and undermine the validity of the experiment.

Question 7

How does a scientific theory differ from a scientific hypothesis?

Accepted Answer

Scientific hypotheses are proposed explanations for specific phenomena. In contrast, scientific theories are well-accepted explanations for a wide range of phenomena that have been repeatedly tested and supported by empirical evidence. Theories are typically more general than hypotheses, and they provide overarching frameworks for understanding complex phenomena.

Question 8

Use the following information when answering the following question.
In 1668, Francesco Redi performed a series of experiments on spontaneous generation. He began by putting similar pieces of meat into eight identical jars. Four jars were left open to the air, and four were sealed. He then did the same experiment with one variation: Instead of sealing four of the jars completely, he covered them with gauze (the gauze excluded the flies while allowing the meat to be exposed to air). In both experiments, he monitored the jars and recorded whether or not maggots (young flies)appeared in the meat.
In both experiments, flies appeared in all of the open jars and only in the open jars. Which one of the following statements is correct?

Accepted Answer

The experiment supports the hypothesis that maggots arise only from eggs laid by adult flies, as flies appeared only in the open jars where they could lay their eggs on the meat. The fact that no maggots appeared in the sealed or covered jars supports this conclusion. The experiment was well designed and the use of only one type of meat was not a significant limitation. Additionally, the experiment was run for a sufficient amount of time to observe the appearance of maggots.

Question 9

The following experiment is used for the following question.
A researcher discovered a species of moth that lays its eggs on oak trees. Eggs are laid at two distinct times of the year: early in spring when the oak trees are flowering and in midsummer when flowering is past. Caterpillars from eggs that hatch in spring feed on oak flowers and look like oak flowers, but caterpillars that hatch in summer feed on oak leaves and look like oak twigs.
How does the same population of moths produce such different-looking caterpillars on the same trees? To answer this question, the biologist caught many female moths from the same population and collected their eggs. He put at least one egg from each female into eight identical cups. The eggs hatched, and at least two larvae from each female were maintained in one of the four temperature and light conditions listed below.
$\begin{array}{l|l}
\text { Temperature } & \text { Day Length } \
\hline \text { Springlike } & \text { Springlike } \
\hline \text { Springlike } & \text { Summerlike } \
\hline \text { Summerlike } & \text { springlike } \
\hline \text { Summerlike } & \text { summerlike }
\end{array}$

In each of the four environments, one of the caterpillars was fed oak flowers, the other oak leaves. Thus, there were a total of eight treatment groups (4 environments × 2 diets).
Recall that in the experiment, caterpillars born in the spring looked like flowers, and caterpillars born in the summer looked like twigs. What is the most likely selective advantage for this difference in body shape?

Accepted Answer

Looking like their food source lets the caterpillars blend into their surroundings and reduce the chances of being detected by predators. This provides a selective advantage in terms of survival, as caterpillars that are more successful at avoiding predation will be more likely to survive and reproduce.

Question 10

Which of the following are qualities of any good scientific hypothesis?
I.It is testable.
II.It is falsifiable.
III.It produces quantitative data.
IV.It produces results that can be replicated.

Accepted Answer

A good scientific hypothesis must be testable, meaning that it can be empirically investigated through observation or experimentation. It must also be falsifiable, meaning that it can potentially be proven false through additional evidence. The production of quantitative data and replicable results are desirable qualities but not necessary for a good hypothesis.

Question 11

The best experimental design ________.

Accepted Answer

A good experimental design should include a large sample size for each condition, a control group, and alter only one condition between the control and experimental groups. Therefore, the best choice is D, which includes all these components.

Question 12

The following experiment is used for the following question.
A researcher discovered a species of moth that lays its eggs on oak trees. Eggs are laid at two distinct times of the year: early in spring when the oak trees are flowering and in midsummer when flowering is past. Caterpillars from eggs that hatch in spring feed on oak flowers and look like oak flowers, but caterpillars that hatch in summer feed on oak leaves and look like oak twigs.
How does the same population of moths produce such different-looking caterpillars on the same trees? To answer this question, the biologist caught many female moths from the same population and collected their eggs. He put at least one egg from each female into eight identical cups. The eggs hatched, and at least two larvae from each female were maintained in one of the four temperature and light conditions listed below.
$\begin{array}{l|l}
\text { Temperature } & \text { Day Length } \
\hline \text { Springlike } & \text { Springlike } \
\hline \text { Springlike } & \text { Summerlike } \
\hline \text { Summerlike } & \text { springlike } \
\hline \text { Summerlike } & \text { summerlike }
\end{array}$

In each of the four environments, one of the caterpillars was fed oak flowers, the other oak leaves. Thus, there were a total of eight treatment groups (4 environments × 2 diets).
In every case, caterpillars that feed on oak flowers look like oak flowers. In every case, caterpillars that were raised on oak leaves looked like twigs. These results support which of the following hypotheses?

Accepted Answer

The experiment showed that regardless of the temperature and day length conditions, caterpillars that were fed oak flowers looked like flowers, and those fed oak leaves looked like twigs. This indicates that diet, not environmental conditions or genetics, triggers the development of different caterpillar appearances.

Question 13

Use the following information when answering the following question.
In 1668, Francesco Redi performed a series of experiments on spontaneous generation. He began by putting similar pieces of meat into eight identical jars. Four jars were left open to the air, and four were sealed. He then did the same experiment with one variation: Instead of sealing four of the jars completely, he covered them with gauze (the gauze excluded the flies while allowing the meat to be exposed to air). In both experiments, he monitored the jars and recorded whether or not maggots (young flies)appeared in the meat.
What hypothesis was being tested in the initial experiment with open versus sealed jars?

Accepted Answer

The experiment was designed to test the hypothesis that maggots arise spontaneously from meat left out in the open, rather than from eggs laid by adult flies. By comparing the open jars (in which maggots appeared) to the sealed jars (in which maggots did not appear), Redi was able to disprove the idea of spontaneous generation and support the hypothesis that maggots come from eggs laid by flies.

Question 14

A controlled experiment ________.

Accepted Answer

A controlled experiment includes at least two groups, one of which does not receive the experimental treatment, in order to compare the effects of the treatment. The other choices do not fully describe a controlled experiment. A controlled experiment may or may not be repeated many times depending on the specific research question and design. A controlled experiment may include groups that differ by one variable, but the key aspect is that the researcher controls all other variables so that any observed differences between the groups can be attributed to the treatment.

Question 15

The following experiment is used for the following question.
A researcher discovered a species of moth that lays its eggs on oak trees. Eggs are laid at two distinct times of the year: early in spring when the oak trees are flowering and in midsummer when flowering is past. Caterpillars from eggs that hatch in spring feed on oak flowers and look like oak flowers, but caterpillars that hatch in summer feed on oak leaves and look like oak twigs.
How does the same population of moths produce such different-looking caterpillars on the same trees? To answer this question, the biologist caught many female moths from the same population and collected their eggs. He put at least one egg from each female into eight identical cups. The eggs hatched, and at least two larvae from each female were maintained in one of the four temperature and light conditions listed below.
$\begin{array}{l|l}
\text { Temperature } & \text { Day Length } \
\hline \text { Springlike } & \text { Springlike } \
\hline \text { Springlike } & \text { Summerlike } \
\hline \text { Summerlike } & \text { springlike } \
\hline \text { Summerlike } & \text { summerlike }
\end{array}$

In each of the four environments, one of the caterpillars was fed oak flowers, the other oak leaves. Thus, there were a total of eight treatment groups (4 environments × 2 diets).
Which one of the following is not a plausible hypothesis that can be tested in this experiment?

Accepted Answer

The experiment only varies temperature and day length, not elevation, so it is not possible to test the hypothesis that differences in air pressure trigger the development of different types of caterpillars. A, B, and D are all plausible hypotheses that could be tested in the experiment.

Question 16

A friend of yours calls to say that his car would not start this morning. He asks for your help. You say that you think the battery must be dead. If so, then jump-starting the car from a good battery will solve the problem. In doing so, you are ________.

Accepted Answer

By saying that the battery must be dead, you are stating a hypothesis and then using that hypothesis to make a testable prediction that jump-starting the car from a good battery will solve the problem.

Question 17

A scientist, who wants to study the effects of nitrogen on wheat plants, sets up an experiment with 4 groups of wheat plants: group A gets 20 pounds per acre, group B gets 40 pounds per acre, group C gets 60 pounds per acre, and group D gets 0 pounds per acre. Which of the following is the control group?

Accepted Answer

The control group is the group that does not receive the treatment being tested, in this case, the group that does not receive any nitrogen fertilizer. Therefore, group D (which receives 0 pounds per acre) is the control group.

Question 18

The following experiment is used for the following question.
A researcher discovered a species of moth that lays its eggs on oak trees. Eggs are laid at two distinct times of the year: early in spring when the oak trees are flowering and in midsummer when flowering is past. Caterpillars from eggs that hatch in spring feed on oak flowers and look like oak flowers, but caterpillars that hatch in summer feed on oak leaves and look like oak twigs.
How does the same population of moths produce such different-looking caterpillars on the same trees? To answer this question, the biologist caught many female moths from the same population and collected their eggs. He put at least one egg from each female into eight identical cups. The eggs hatched, and at least two larvae from each female were maintained in one of the four temperature and light conditions listed below.
$\begin{array}{l|l}
\text { Temperature } & \text { Day Length } \
\hline \text { Springlike } & \text { Springlike } \
\hline \text { Springlike } & \text { Summerlike } \
\hline \text { Summerlike } & \text { springlike } \
\hline \text { Summerlike } & \text { summerlike }
\end{array}$

In each of the four environments, one of the caterpillars was fed oak flowers, the other oak leaves. Thus, there were a total of eight treatment groups (4 environments × 2 diets).
Recall that eggs from the same female were exposed to each of the eight treatments used. This aspect of the experimental design tested which of the following hypotheses?

Accepted Answer

The experiment design, where eggs from the same female moth were exposed to each of the eight treatments, tests the hypothesis that the differences in caterpillar characteristics are genetic. If the eggs from the same female moth produce different-looking caterpillars across the different environments, it suggests that the differences are due to genetics rather than diet, day length, or environmental factors like air pressure. Therefore, choice (D) is the correct answer.

Question 19

The evolution of one species into two or more species as a result of different populations becoming reproductively isolated from each other is best termed as ________.

Accepted Answer

The process described is known as adaptive radiation, where one species diverges into multiple new species due to various environmental factors that cause reproductive isolation. Creationism is a belief system that posits that a higher power created all living things, while natural selection is a mechanism by which advantageous traits are favored in a population over time, leading to evolution. Prototype refers to an initial or preliminary version of a product or design.

Question 20

Following a scientific method, which of the following is the correct order of steps?

Accepted Answer

The scientific method typically begins with observation, which leads to the creation of a hypothesis. The hypothesis is then tested through experimentation and the results are analyzed to draw a conclusion. Finally, the results are communicated to the scientific community. Therefore, option D is the correct order of steps.

Quiz 1: Evolution, the Themes of Biology, and Scientific Inquiry