16. What is the name of the protein that is used to form the initial glycogen primer?
(A) phosphoporin
(B) glucokinase
(C) glycoporin
(D) glycogenin
(E) pyrophorin

12. Which of the following statements regarding photoperiodism is false? (A) Photoperiodism is the physiological reaction of organisms to the length of a dark period. It occurs in both plants and animals. (B) Many flowering plants (angiosperms) use photoreceptors such as phytochrome and cryptochrome to sense photoperiod. (C) Long-day plants flower when the night length falls below their critical photoperiod. (D) The shoot apical meristem that senses the photoperiod leading to its transition from a vegetative (leaf) bud to a reproductive (flower) bud. (E) Day-neutral plants such as maize do not initiate flowering based on photoperiodism.

13. All female mammals have one active X chromosome per cell instead of two. What causes this to happen? (A) attachment of methyl (-CH3) groups to the X chromosome that will remain active (B) only the X chromosome from mother will remain active (C) inactivation of the XIST gene on the X chromosome derived from the male parent (D) activation of the BARR gene on one X chromosome, which then becomes inactive (E) activation of the XIST gene on the X chromosome that will become the Barr body

14. A genetic map shows the map distance. The units of genetic distance are called map units (mu) or centiMorgans (cM). Which of the following indicates the map distance of 23.6 mu between two genes? (A) The distance between two genes is 23.6 millimeters. (B) There are 23.6 other genes between the two genes of interest. (C) The co-mutation rate of two genes is 23.6%. (D) The survival rate of the offspring is 23.6%. (E) 23.6% of the offspring exhibit recombination between the two genes.

15. A researcher is analyzing the immune response of a patient following the patient's exposure to an unknown agent while out of the country. The patient's blood is found to have a high proportion of lymphocytes with CD8 surface proteins. What is the likely cause? (A) The patient encountered a bacterial infection which elicited CD8 marked T cells. (B) The disease must have been caused by a multicellular parasite, such as can be encountered in polluted water sources. (C) The CD8 proteins would be discharged from these lymphocytes to lyse the infected cells. (D) The CD8 proteins marked the surfaces of cytotoxic 'T cells to attack virus-infected host cells. (E) CD8 marks the surface of cells that accumulate after the infection is over and signal patient recovery.

17. Which of the following pairs of amino acids could form electrostatic interactions by their side chains? (A) Serine and phenylalanine (B) Glutamic acid and arginine (C) Alanine and glutamine (D) Leucine and cysteine (E) Histidine and Isoleucine

18. In humans, gluconeogenesis: (A) can result in the conversion of protein into blood glucose. (B) helps to reduce blood glucose after a carbohydrate-rich meal. (C) is activated by the hormone insulin. (D) is essential in the conversion of fatty acids to glucose. (E) requires the enzyme hexokinase.

19. Which of the following is (are) NOT found as covalently attached anchors in lipid-linked proteins? (A) isoprenoid groups (B) fatty acids (C) cholesterol and other sterols (D) glycosylphosphatidyl inositol groups (E) All of the above are found as covalently attached anchors in lipid-linked proteins.

20. Aspirin inhibits the synthesis of which of the following sets of eicosanoids? (A) Prostaglandin E2 and leukotriene A4 (B) Thromboxane A2 and leukotriene C4 (C) Prostaglandin F2 and thromboxane A2 (D) Prostaglandin A2 and 5-hydroperoxyeicosatetraenoic acid (E) Thromboxane A2 and 5-hydroperoxyeicosatetraenoic acid

21. In which metabolic pathway does glucose-6-phosphate dehydrogenase play a key role? (A) glycogenesis (B) glycolysis (C) gluconeogenesis (D) glycogenolysis (E) pentose phosphate pathway

22.Which of the following explains are the enzyme effects? (A) Enzymes release products very rapidly (B) Enzymes can lower product energy (C) An enzyme stabilizes the transition state of the reaction (D) An enzyme can convert a normally endergonic reaction into an exergonic reaction (E) An enzyme lowers the energy of activation only for the forward reaction