Full SAT Biology Practice Test 2: Part B

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Question 20 questions

Time 15 minutes

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1. The diagram shows the muscles involved in extending the arm. Which actions result in this movement?

A. Muscle 1 relaxes while muscle 2 contracts.
B. Muscle 1 contracts while muscle 2 relaxes.
C. Muscle 1 contracts, and then both muscles relax.
D. Muscle 1 and muscle 2 both relax the same time.
E. Muscle 1 and muscle 2 both contract at the same time.

2. Which cellular process is responsible for the change shown below?

A. Closing of stomata
B. Slowing of photosynthesis
C. Reduction in protein synthesis
D. Degradation of the cytoskeleton
E. Decreased pressure in the vacuole

3. During which phase of mitosis do the centromeres split?

A. Anaphase
B. Cytokinesis
C. Metaphase
D. Prophase
E. Telophase

4. Which of the following plays an important role in the human immune system

A. Femur
B. Metatarsals
C. Patella
D. Scapula
E. Vertebra

5. How do enzymes help to carry out biochemical reactions?

A. By decreasing the energy of the reactants
B. By increasing the activation energy of the reaction
C. By decreasing the activation energy of the reaction
D. By increasing the energy of the products of the reaction
E. By decreasing the energy of the products of the reaction

6. In which plants is the haploid gametophyte generation dominant?

I. Angiosperms

II. Gymnosperms

III. Horsetails, ferns, club mosses (lycophytes and pterophytes)

IV. True mosses, liverworts, and hornworts (bryophtyes)

A. I only
B. I and II
C. I, II, and III
D. III and IV
E. IV only

7. Which of the following uses a countercurrent exchange system?

I. Gills

II. Kidneys

III. Intestines

IV. Lungs

A. I and III only
B. II and IV only
C. I, II, and III
D. I, II, and IV
E. I, II, III, and IV

8. Which describes the cause of eutrophication in lakes?

A. A lack of oxygen
B. A lack of sunlight
C. A lack of nutrients
D. An excess of oxygen
E. An excess of nutrients

9. Two parents with dimples have a child with no dimples. The allele Dfor dimples is dominant. What are the possible genotypes of the parents?

I. DDand Dd

II. Ddand Dd

III. DDand dd

A. I only
B. II only
C. I or II
D. II or III
E. I, II, or III

10. Which of these are relationships in which one species benefits at the expense of another?

I. Commensalism

II. Competition

III. Parasitism

IV. Predation

A. III only
B. III and IV
C. I, II, and III
D. II, III, and IV
E. I, II, III, and IV

11. What is the most likely role of zooplankton in an aquatic ecosystem?

A. Producer
B. Primary consumer
C. Secondary consumer
D. Tertiary consumer
E. Decomposer

12. Which refers to the degree to which a phenotype is determined by genetic variation in a population?

A. Fitness
B. Heritability
C. Limited environmental resources
D. Overproduction of offspring
E. Phenotypic variation

13. Which of the following is the smallest unit that can evolve through natural selection?

A. Cell
B. Clade
C. Organism
D. Population
E. Species

14. Which of the following leads to a replacement of the plant community in an ecosystem undergoing succession?

A. Pollution
B. Herbivory
C. Parasitism
D. Abiotic factors
E. Intraspecific competition

15. Which of the following describes a possible path of a carbon atom among atmospheric carbon dioxide, the tissues of a consumer, and the tissues of a producer?

A. Consumer←→producer←→atmosphere←→producer
B. Producer←→consumer←→atmosphere←→consumer
C. Producer←→atmosphere←→consumer←→atmosphere
D. Atmosphere←→producer←→atmosphere←→consumer
E. Consumer←→atmosphere←→producer←→atmosphere

16. Which of the following includes organisms that are able to utilize nitrogen in the form of nitrogen gas (N2)?

A. Producers
B. Primary consumers
C. Secondary consumers
D. Tertiary consumers
E. Decomposers

17. The graph shows the body size distribution in a population. Which statement describes the effects of directional selection on the distribution?

A. The mean shifts, and the curve remains the same.
B. The mean shifts, and the curve becomes narrower.
C. The mean remains the same, and the curve becomes wider.
D. The mean remains the same, and the curve becomes narrower.
E. The mean shifts to both the left and the right, and two new curves form.

18. Which of the following characteristics are present in monocots?

A. I only
B. II only
C. I and II
D. I and III
E. II and III

19. Identify the organism shown using the following dichotomous key.

A. Acari
B. Araneae
C. Opiliones
D. Scorpiones
E. Pseudoscorpiones

20. Within the animal lineage leading to humans, which of the following structures evolved first?

A. Bone
B. Cranium
C. Jaws
D. Notochord
E. Vertebrae