AP Biology Practice Test 20

Test Information

Question 12 questions

Time 15 minutes

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1. snRNPs are most closely associated with which of the following?

2. Which of the following is correct about vaccination?

Questions 3-4 refer to the following information.

A scientist wanted to understand the role of the gonads and their hormones in the development of the sex of an individual. He carried out an experiment with rabbit embryos while they were still in the mothers' uterus at a stage before sex differences were observable. He surgically removed the portion of each embryo that would develop into ovaries or testes. When the babies were born, he made note of their chromosome sex and the sexual differentiation of the genitals. Here are his data.

Appearance of Genitals

Sex Chromosome of IndividualNo Surgery
Embryonic Gonad Removed





3. Which of the following statements is a correct conclusion to draw from this experiment?

4. What is the correct prediction if the researcher were to replace the surgically removed gonad with a crystal of testosterone?

5. Which of the following statements about meiosis is correct?

6. Which of the following is correct about organisms that are the first to colonize a habitat undergoing ecological succession?

7. In the microscopic world of a pond, paramecia are ferocious predators that prey on smaller protists. In a classic experiment, two species of paramecia were grown separately in culture. The species in culture A was P. caudatum. The species in culture B was P. bursaria. Then the two species were combined in one culture dish (culture C).

Which of the following is the most likely explanation for the growth pattern of the two populations combined in culture C?

8. When driving from east to west in the U.S. from a forest ecosystem to grasslands, trees gradually give way to grasses. Which of the following is the critical factor responsible for this shift?

9. Which of the following is an example of a cline?

10. Which of the following statements is NOT correct about ancient Earth?

11. Intact chloroplasts are isolated from dark-green leaves by low-speed centrifugation and placed into six tubes containing cold buffer. A blue dye, DPIP, which turns clear when reduced, is also added to all the tubes. The amount of decolorization is a function of how much reduction and, therefore, how much photosynthesis occurs. Each tube is exposed to different wavelengths of light. A measurement of the amount of decolorization is made, and the data are plotted on a graph. Although the wavelengths of light vary, the light intensity in each tube is the same.

Which statement below best explains the results of this experiment and the reason for it?

12. Today, two distinctly different beak sizes occur in a single population of finch in an isolated region of West Africa. This finch, the black-bellied seedcracker, is considered a delicacy. The oldest residents of the region remember that all black-bellied seedcrackers used to appear identical. The change in population is shown in the graph.

Which of the following statements best identifies the change in the population of finches and the most likely reason for it?