Download Review for Chapter 6 Test - Changes Over time word document

Review for chapter 6 test - Changes Over Time
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
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1. How do scientists determine the actual age of fossils?
a. relative dating
b. radioactive dating
c. sedimentary dating
d. mold and cast dating
2. What evidence is most important when using relative dating?
a. the half-life of a radioactive element
b. the position of sediment in petrified rock
c. the types of minerals in a petrified fossil
d. the position of fossils in sedimentary rock layers
3. Which term refers to a species that no longer has any living members?
a. molded
b. fossilized
c. extinct
d. petrified
4. Which term refers to a species creating more offspring than can possibly survive?
a. natural selection
b. overproduction
c. evolution
d. variation
5. How do remains become petrified fossils?
a. A sedimentary rock becomes a cast.
b. Molds and casts fill with sediment.
c. Minerals replace all or part of an organism.
d. Sediment replaces all or part of an organism.
Modified True/False
Indicate whether the sentence or statement is true or false. If false, change the identified word or phrase to make the
sentence or statement true.
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6. Gradual change in a species over time is called adaptation. _________________________
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7. Through natural selection, harmful variations gradually accumulate in a species.
_________________________
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8. Darwin thought that species evolved rapidly. _________________________
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9. The theory of punctuated equilibria proposes that species evolve slowly but steadily.
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____ 10. On a branching tree, a species is more closely related to a species on the same branch than to one on a separate
branch. _________________________
Completion
Complete each sentence or statement.
11. The only traits that can be acted upon by natural selection are those that are controlled by
____________________.
12. A new ____________________ can form when a group of individuals become isolated from the main group.
13. Most fossils are found in ____________________ rock.
14. Living things first appeared during the geologic time period known as _________________________.
15. A(n) ____________________ is a well-tested concept that explains a wide range of observations.
Short Answer
Use the diagram to answer each question. (#16 – 20)
16. Did birds evolve from the gliding reptiles called pterosaurs? Explain your reasoning.
17. Would you expect the DNA of crocodilians to be more similar to the DNA of modern birds or the DNA of
turtles? Explain your reasoning.
18. Are pterosaurs more closely related to turtles or to crocodilians? Explain your answer.
19. Name the common ancestor of pterosaurs and crocodilians.
20. List two ancestors of Archaeopteryx.
Essay
21. A horse and a donkey can mate with each other. Their offspring, called a mule, is not fertile. Do horses and
donkeys belong to the same species? Explain your answer.
22. A scientist collects wild rabbits that live at sea level and moves them to the mountains. One year later, the
scientist discovers that the same rabbits have larger lungs, which help them breathe the thin mountain air. The
scientist returns the rabbits to sea level. Will the offspring of the rabbits have larger-than-normal lungs?
Explain.
23. Potassium-40 breaks down to form argon-40. Suppose a rock contains 5 grams of potassium-40 and 15 grams of
argon-40. How many half-lives has the potassium-40 undergone? Explain your answer.
24. What is a mass extinction? What do scientists hypothesize causes mass extinctions?
25. How did studying selective breeding help Darwin develop his theory of evolution?