1. Evolution, the Themes of Biology, and Scientific Inquiry

2. Which of the following is not a theme that unifies biology?
systems biology
emergent properties
inductive reasoning
reductionism
genomics
Answer: d

3. Which of the following is not a theme that unifies biology?
systems biology
emergent properties
inductive reasoning
reductionism
genomics 3

4. What is the correct order (from small to large)?
cells, organelles, organ system, community, ecosystems
molecules, organism, population, communities, biosphere
molecules, cells, tissues, ecosystems, communities
organelles, cells, population, biosphere, ecosystems
cells, organs, population, ecosystems, communities
Answer: b 4

5. What is the correct order (from small to large)?
cells, organelles, organ system, community, ecosystems
molecules, organism, population, communities, biosphere
molecules, cells, tissues, ecosystems, communities
organelles, cells, population, biosphere, ecosystems
cells, organs, population, ecosystems, communities 5

6. All of the gray squirrels that inhabit an oak forest describes a/an:
ecosystem
biosphere
community
population
colony
Answer: d

7. All of the gray squirrels that inhabit an oak forest describes a/an:
ecosystem
biosphere
community
population
colony

8. Which of the following scientific studies would represent an example of a “systems biology” approach?
measuring the effect of an invading insect that eats oak leaves on the numbers of oak trees and on any subsequent changes in the number and types of decomposer fungi in the soil
discovering the structure of an enzyme that is important in digestion of protein
comparing the microscopic structure of leaves of two different species of magnolias
measuring the reproductive rate of emperor penguins during exceptionally warm and exceptionally cold years
comparing the DNA sequence of two closely related plants and inferring their evolutionary histories
Answer: a
In the past, most research has been conducted on one or two levels of complexity (e.g., cells or population levels). Recently, however, scientists or teams of scientists have been studying how processes at one level affect processes on other scales. This question is designed to help students see connections among levels. Answers C–E address scientific questions at only one level: C is a study at the tissue level, D is a study at the population level, and E is a study at the molecular level. Answer B is likely a study simply at the molecular level, but a student might argue that it addresses two levels—molecular and cellular. It could certainly be expanded to a systems study if the scientists also studied molecular forces and folding of the protein chain. Answer A is likely the best answer because the two-species interaction between the invading insect and the oak (community level) affects the abundance of oak trees (population level) and the process of decomposition (ecosystem level). A possible extension of this question would be to ask students to broaden all the answers into systems biology studies. 8

9. Which of the following scientific studies would represent an example of a “systems biology” approach?
measuring the effect of an invading insect that eats oak leaves on the numbers of oak trees and on any subsequent changes in the number and types of decomposer fungi in the soil
discovering the structure of an enzyme that is important in digestion of protein
comparing the microscopic structure of leaves of two different species of magnolias
measuring the reproductive rate of emperor penguins during exceptionally warm and exceptionally cold years
comparing the DNA sequence of two closely related plants and inferring their evolutionary histories 9

10. Like jackrabbits, elephants have many blood vessels in their ears that help them cool their bodies by radiating heat. Which of the following statements about this radiated energy would be accurate?
The original source of the energy was the sun.
The energy will be recycled through the ecosystem.
The radiated energy will be trapped by predators of the elephants.
More energy is radiated in cold conditions than in hot conditions.
More energy is radiated at night than during the day.
Answer: a
Energy is a concept that is essential for all students to understand. This question will help students understand a number of ideas about energy. Answer A is the correct answer; students should understand that the energy from the sun powers all living systems (except deep-ocean vent communities). Energy is lost to the system as heat, whereas atoms can be used over and over again; thus, answer B is incorrect. Answer C is related to answer B and is incorrect because the heat that is radiated from the ears is not available to other organisms—only the energy stored in the tissues of the jackrabbit is available to the predator. Answers D and E are incorrect for the same reason—that more heat is radiated when the jackrabbit is warmer (either in hot conditions or during the day). 10

11. Like jackrabbits, elephants have many blood vessels in their ears that help them cool their bodies by radiating heat. Which of the following statements about this radiated energy would be accurate?
The original source of the energy was the sun.
The energy will be recycled through the ecosystem.
The radiated energy will be trapped by predators of the elephants.
More energy is radiated in cold conditions than in hot conditions.
More energy is radiated at night than during the day. 11

12. The idea that form and function are related would not be exemplified by which of the following examples?
Cells in the intestinal lining of vertebrates have many small projections that increase the surface area for absorption of nutrients.
Plants that live in dry areas have large roots for absorbing water.
Seeds that are dispersed by wind are very light.
Fish that swim rapidly have bodies that are streamlined.
none of the above
Answer: e
The relationship between form and function is very important and results from the action of natural selection. In this question, all answers show a relationship between form and function, and therefore none of them connects correctly to the stem. 12

13. The idea that form and function are related would not be exemplified by which of the following examples?
Cells in the intestinal lining of vertebrates have many small projections that increase the surface area for absorption of nutrients.
Plants that live in dry areas have large roots for absorbing water.
Seeds that are dispersed by wind are very light.
Fish that swim rapidly have bodies that are streamlined.
none of the above 13

14. Imagine that you have just discovered a new multicellular but microscopic organism that swims in ponds. You see that it is propelled by cilia on the outside of the organism. What can you say about the evolutionary relationships of this organism?
The presence of cilia shows that it is more closely related to Paramecium than to humans.
The presence of cilia shows that it shares a common ancestor with Paramecium and humans.
It is probably closely related to pond algae.
It is probably most closely related to prokaryotes.
The presence of cilia demonstrates the diversity, but not the unity, of life.
Answer: b
It can seem contradictory to students that “evolution can account for both the unity and diversity of life,” but this is an important concept for them to understand. Organisms share traits that they have inherited from a common ancestor (the unity of life) but differ in traits if natural selection, or perhaps genetic drift, leads to change (the diversity of life). Cilia occur in both Paramecium and humans and, most notably, have the same internal structure. This pattern shows that they have a common ancestor (i.e., answer B is correct), but the differences between Paramecium and humans show that they have diverged over evolutionary time. The mere presence of cilia cannot help us decide what the new organism is closely related to (either Paramecium as in answer A, pond algae as in answer C, or prokaryotes as in answer D). Answer E is incorrect because the presence of cilia shows the unity, not the diversity, of life. 14

15. Imagine that you have just discovered a new multicellular but microscopic organism that swims in ponds. You see that it is propelled by cilia on the outside of the organism. What can you say about the evolutionary relationships of this organism?
The presence of cilia shows that it is more closely related to Paramecium than to humans.
The presence of cilia shows that it shares a common ancestor with Paramecium and humans.
It is probably closely related to pond algae.
It is probably most closely related to prokaryotes.
The presence of cilia demonstrates the diversity, but not the unity, of life. 15

16. Examine the figure on the next slide and predict which species pair has the most similar DNA sequence.
vegetarian tree finch (Platyspiza crassirostris) and mangrove finch (Cactospiza heliobates)
medium tree finch (Camarhynchus pauper) and large tree finch (Camarhynchus psittacula)
large tree finch (Camarhynchus psittacula) and small tree finch (Camarhynchus parvulus)
sharp-beaked ground finch (Geospiza difficilis) and large ground finch (Geospiza magnirostris)
No such predictions are possible.
Answer: c
The goal of this question is to make students actually look at the “family tree”—it’s very easy to just glance at it and think you understand it. Of the choices given, only answer C gives two species that are each other’s closest relative, e.g., “sister species.” 16

17. 17

18. Examine the figure on the previous slide and predict which species pair has the most similar DNA sequence.
vegetarian tree finch (Platyspiza crassirostris) and mangrove finch (Cactospiza heliobates)
medium tree finch (Camarhynchus pauper) and large tree finch (Camarhynchus psittacula)
large tree finch (Camarhynchus psittacula) and small tree finch (Camarhynchus parvulus)
sharp-beaked ground finch (Geospiza difficilis) and large ground finch (Geospiza magnirostris)
No such predictions are possible. 18

19. Which of the following is an activity that would not reflect the practice of science?
Science is typically performed alone in the lab.
Data are typically collected by teams of students and experienced researchers.
Scientists typically reexamine conclusions or repeat experiments from other large, famous labs.
Scientists who work in forests studying ecology often collaborate closely with geneticists who work only in the lab.
The practice of science results in a discovery that lends new insight, and technology involves how this new insight will be applied to develop a new drug.
Answer: a 19

20. Which of the following is an activity that would not reflect the practice of science?
Science is typically performed alone in the lab.
Data are typically collected by teams of students and experienced researchers.
Scientists typically reexamine conclusions or repeat experiments from other large, famous labs.
Scientists who work in forests studying ecology often collaborate closely with geneticists who work only in the lab.
The practice of science results in a discovery that lends new insight, and technology involves how this new insight will be applied to develop a new drug. 20

21. An experimental study is conducted to determine whether or not a new drug reduces high blood pressure. The change in systolic and diastolic blood pressure values of the participants represents the:
independent variable
dependent variable
hypothesis
theory
control group
Answer: b

22. An experimental study is conducted to determine whether or not a new drug reduces high blood pressure. The change in systolic and diastolic blood pressure values of the participants represents the:
independent variable
dependent variable
hypothesis
theory
control group

23. Nearly half a century ago, D. W
Nearly half a century ago, D. W. Kaufman investigated the effect of prey camouflage on predation. Kaufman tested the hypothesis that the amount of contrast between the coat color of a mouse and the color of its surroundings would affect the rate of nighttime predation by owls. He also hypothesized that the color contrast would be affected by the amount of moonlight. In this exercise, you will analyze data from his owl-mouse predation studies. Pairs of mice (Peromyscus polionotus) with different coat colors, one light brown and one dark brown, were released simultaneously into an enclosure that contained a hungry owl. The researcher recorded the color of the mouse that was first caught by the owl. If the owl did not catch either mouse within 15 minutes, the test was recorded as a zero. The release trials were repeated multiple times in enclosures with either a dark-colored soil surface or a light-colored soil surface. The presence or absence of moonlight during each assay was recorded.

24. The graph shows data from the light-colored soil enclosure
The graph shows data from the light-colored soil enclosure. There is one dependent variable and more than one independent variable on the graph. What are the independent variables, the variables that were manipulated by the researcher?
the color of the soil and the presence or absence of moonlight
the presence or absence of moonlight and the number of mice caught
mouse coat color and the presence or absence of moonlight
mouse coat color and the number of mice caught
Answer: c

25. The graph shows data from the light-colored soil enclosure
The graph shows data from the light-colored soil enclosure. There is one dependent variable and more than one independent variable on the graph. What are the independent variables, the variables that were manipulated by the researcher?
the color of the soil and the presence or absence of moonlight
the presence or absence of moonlight and the number of mice caught
mouse coat color and the presence or absence of moonlight
mouse coat color and the number of mice caught

26. What is the dependent variable, the response to the variables being tested?
the presence or absence of moonlight
the mouse coat color
the number of mice caught
the color of the soil
Answer: c

27. What is the dependent variable, the response to the variables being tested?
the presence or absence of moonlight
the mouse coat color
the number of mice caught
the color of the soil

28. Now you will look at data from two different enclosures: one with light-colored soil (left), and one with dark-colored soil (right). How many dark brown mice were caught in the light-colored soil enclosure on a moonlit night? 12 17 19 37
Answer: c

29. Now you will look at data from two different enclosures: one with light-colored soil (left), and one with dark-colored soil (right). How many dark brown mice were caught in the light-colored soil enclosure on a moonlit night? 12 17 19 37

30. On a moonlit night, would a dark brown mouse be more likely to escape predation by owls on dark- or light-colored soil? What data support your conclusion?
On light-colored soil; the lowest level of predation was light brown mice on light soil.
On dark-colored soil; fewer light brown mice than dark brown mice were caught on light soil under no moon.
On dark-colored soil; fewer dark brown mice were caught on dark soil than on light soil under a full moon.
On light-colored soil; fewer dark brown mice were caught on dark soil than on light soil under a full moon.
Answer: c

31. On a moonlit night, would a dark brown mouse be more likely to escape predation by owls on dark- or light-colored soil? What data support your conclusion?
On light-colored soil; the lowest level of predation was light brown mice on light soil.
On dark-colored soil; fewer light brown mice than dark brown mice were caught on light soil under no moon.
On dark-colored soil; fewer dark brown mice were caught on dark soil than on light soil under a full moon.
On light-colored soil; fewer dark brown mice were caught on dark soil than on light soil under a full moon.

32. What combination of independent variables led to the highest predation level in enclosures with light-colored soil?
light brown coat with no moon
light brown coat with full moon
dark brown coat with full moon
dark brown coat with no moon
Answer: d

33. What combination of independent variables led to the highest predation level in enclosures with light-colored soil?
light brown coat with no moon
light brown coat with full moon
dark brown coat with full moon
dark brown coat with no moon