20. The end product of glycolysis is
(A)acetyl-CoA
(B) citrate
(C) pyruvate
(D) oxaloacetate
(E) oxygen

16. The slow block to polyspermy during fertilization are dependent on (A) the entrance of potassium ions into the egg (B) the departure of sodium ions from the egg (C) the entrance of calcium ions into the egg (D)the departure of bydrogen ions from the egg (E) the entrance of chloride ions into the egg

17. Crossing over of chromosomes normally takes place during which of the following processes? (A) meiosis II (B) meiosis I (C) metaphase (D) mitosis(E) prometaphase

18. Cellular respiration (A) occurs only in animal cells because plants carry on photosynthesis (B) is the reverse process of photosynthesis (C)occurs at the same rate throughout all cells of the body (D) is the mechanism that living organisms use to convert glucose intoenergy (E) is the only cellular mechanism that yields ATP

複選題19. Which statement regarding plant auxin is correct? (A) It is synthesized in active growing cells and transported up or down to promote cell growth. (B) The antagonistic interactions between cytokinin and auxin shape the morphology of shoots. (C) Accumulation of auxin in axillary buds will promote lateral shoot development. (D) When the sunlight shines on the stem with an angle, auxin will accumulate in the lighting side of the stem to promote cell elongation. (E) In response to gravity, auxin will accumulate in the upper side of roots to promote cell elongation.

21. During the Krebs cycle, (A)electrons and H+ are transferred to coenzymes NAD+ and FAD (B) substrate-level phosphorylation occurs (C)molecules of carbon dioxide are formed (D) oxaloacetate is regenerated (E) all of these

複選題22. Which statement about how some plants benefit from the presence of soil microbes is correct? (A) Through their mycorrhizal interactions with fungi, plant roots can acquire nutrients with less bioenergy. (B) Most beneficial microbes can form a symbiosis with both monocot and dicot plants. (C) Upon establishment of symbiosis, these microbes form special compartments randomly inside the root. (D)By interactions with soil bacteria, some plant roots can fix nitrogen gas directly.(E) Plant roots sometimes obtain organic molecules from these beneficial microbes.

23. Fermentation (A) produces more ATP than is liberated in the hydrogen transfer series (B) may occur in a muscle under anaerobic conditions (C) breaks down glucose in reaction with oxygen (D) is restricted to yeasts (E) none of these

24. Which of the following sequences is most likely as a restriction site? (A)5 ' -AATTCT-3 ' (B) 5 ' -AATATT-3 ' (C)5 ' -AAAATT-3 ' (D) 5 ' -ACTACT-3 ' (E) 5 ' -TTCCTT-3 '

25. Which defensive chemical is incorrectly paired with a function? (A) antibodies—pathogen neutralization (B) cytokines—immune cell stimulation (C) histamines—dilate capillaries (D) perforins—lysis (E) lysozymes—cause fevers

26. Which part is not required for the feeling of hearing or equilibrium in humans? (A)utricle (B) vestibular canal (C) ocelli (D)incus (E) hair cells