13. Prednisone is often prescribed to individuals who are suffering from redness and swelling due to allergies. Patients on prednisone typically experience reduced redness and swelling. Based on these responses, what natural hormone does prednisone mimic?
(A) mineralocorticoid
(B) glucocorticoid
(C) estrogen
(D) progestin

9. What part of the respiratory system does cigarette smoke most adversely affect? (A) alveoli (B) trachea (C) bronchi (D) diaphragm

10. Which molecule is least likely to be able to pass through a capillary wall? (A) an enzyme (B) a sodium ion (C) glucose (D) oxygen

11. What type of immune response is always disadvantageous to a person? (A) inflammatory (B) humoral (C) autoimmune (D) complement-mediated

12. The nitrogenous waste product in bears (mammals) is _____ , while most saltwater fish get rid of wastes through _____.(A) ammonia； urea (B) uric acid； urea (C) urea； ammonia (D) ammonia； uric acid

14. Asthenozoospermia is a medical condition that is characterized by reduced sperm motility. What structure of the sperm is likely affected in a man who has asthenozoospermia? (A) acrosome (B) head (C) middle piece (D) flagellum

15. The gap between the transmitting and receiving neurons in a chemical synapse is known as the (A) node of Ranvier. (B) ion channel. (C) gap junction. (D) synaptic cleft.

16. Which class of sensory receptors responds to stimuli such as touch, pressure, stretching, and sound? (A) thermoreceptors (B) mechanoreceptors (C) electromagnetic receptors (D) chemoreceptors

17. Which part of a bone contains red bone marrow? (A) compact bone (B) fibrous connective tissue (C) spongy bone (D) yellow bone marrow

18. Which statement best expresses the concept of natural selection? (A) reproductive success influenced by inherited characteristics (B) inheritance of acquired characteristics (C) change in response to need (D) a process of constant improvement, leading eventually to perfection

19. Which description BEST represents the gradual model of speciation (i.e., the formation of new species)? (A) Speciation occurs regularly as a result of the accumulation of many small changes. (B) An isolated population differentiates quickly from its parent stock as it adapts to its local environment. (C) Speciation occurs under unusual circumstances and therefore transitional fossils are hard to find. (D) Species undergo little change over long periods interrupted only by short periods of rapid change.