READ THESE INSTRUCTIONS!

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1 READ THESE INSTRUCTIONS! A. Please write your name at the top of this page, and on the Scantron sheet; fill in your student ID on the Scantron form. B. Make sure you fill in the exam letter (under your name) on the Scantron (Test no.) as well. C. You must turn in both the exam and the Scantron form, and sign out. D. Read all questions first, and read each question carefully. E. There are a total of 50 questions and 100 points. F. Please don t cheat; it ruins my day, and then I have to ruin yours. 1. The main function of white adipose tissue is: a) contraction b) insulation/cushioning c) support d) energy storage e) thermogenesis 2. Which one of these is not a function of white adipose tissue: a) energy storage b) insulation c) cushioning d) source of metabolic water e) thermogenesis 3. White adipose has lipid droplets: a) multilocular b) unilocular c) dilocular d) bilocular 4. Brown adipose has lipid droplets: a) multilocular b) unilocular c) dilocular d) bilocular 5. Brown adipose has mitochondria than white adipose. a) more b) less c) the same d) brown adipose has no mitochondria e) what are mitochondria?

2 6. Brown fat is responsible for thermogenesis in adult humans. 7. The main factor that varies among animals with genetically different fatness is the of adipocytes. a) number b) size 8. In animals that have different fat levels due to nutrition, etc., adipocyte is the primary variable. a) number b) size 9. Obese subjects often have a) larger adipocytes than normal b) two populations of adipocytes c) more extracellular fat 10. Flexible adipose tissue growth involves: a) new cells being recruited when adipose tissue exceeds some limits b) no new cells are ever recruited c) adipose cells become very flexible, they can bend in half d) muscle growth e) bone growth 11. Which of these is not involved in metabolism and storage of lipid in adipose tissue? a) lipoprotein lipase b) fatty acid synthetase c) hormone sensitive lipase d) acetyl-coa carboxylase e) lipodectin synthase 12. increase(s) the proliferation and differentiation of pre-adipocytes. a) insulin b) growth hormone c) glucocorticoid d) epinephrine 13. In meat animals, fat deposits form first around the kidney and heart, followed by intermuscular, intramuscular and finally subcutaneous adipose depots.

3 14. Lipoprotein lipase is involved in lipid mobilization, whereas hormone-sensitive lipase is involved in lipid synthesis. 15. The following is/are important adipogenic regulatory factor(s) a) myogenin b) PPAR-γ c) myorhelin e) a and c 16. The following is not true of insulin: a) stimulates glucose uptake b) inhibits gluconeogenesis c) stimulates lipogenesis d) produced in liver e) is anabolic 17. Animals that have been genetically selected for meat production (i.e. beef cattle) have improved distribution of muscle weights relative to e.g., dairy cattle 18. Which of the following is/are not a skeletal muscle fiber type: a) slow-twitch, oxidative b) slow-twitch, glycolytic c) fast-twitch, oxidative e) b and c 19. The number of muscle cells is unchanged after birth. 20. By birth only one fiber connects to each nerve, and each fiber contacts many nerves. 21. The contractile apparatus of skeletal muscles is called the a) myocardium b) myofilaria c) sarcoplasmic reticulum d) myofibril e) endomysium

4 22. Red muscle fibers have the following characteristics: a) aerobic metabolism mainly b) anaerobic metabolism mainly c) found in turkey legs d) found in turkey breasts e) a and c 23. Muscle fiber development is essentially complete by the end of the a) first trimester of pregnancy b) second trimester of pregnancy c) third trimester of pregnancy d) puberty e) muscle fibers develop throughout life 24. The following is/are important myogenic regulatory factor(s) a) myogenin b) PPAR-γ c) myorhelin e) a and c 25. Which characteristics are found in slow twitch oxidative muscle cells? a) abundant mitochondria b) abundant vascularization c) small diameter d) small cell size 26. Satellite cells are essentially unfused myoblasts. 27. IGF-I and IGF-II increase the proliferation and differentiation of myoblasts 28. Basic FGF and TGF-β decrease the proliferation and differentiation of myoblasts 29. Heavy lifting exercise increases a) the number of white muscle fibers b) the number of red muscle fibers c) the size of white muscle fibers d) the size of red muscle fibers

5 30. Endurance exercise increases a) the number of white muscle fibers b) the number of red muscle fibers c) the size of white muscle fibers d) the size of red muscle fibers. 31. Whole-body glucose requirements (mg kg 0.75 min -1 ) are in ruminants as compared to non-ruminants a) higher b) lower c) similar 32) Major gluconeogenic substrates for ruminants include a) amino acids b) propionic acid c) glucose e) b and c 33) In ruminants, the gluconeogenic pathways are most active a) just after the previous meal b) just before the next meal c) all day long d) mainly at night e) whenever the brain is concentrating hard, as on a midterm 34) In non-ruminants the gluconeogenic pathways are most active a) just after the previous meal b) just before the next meal c) all day long d) mainly at night e) whenever the brain is concentrating hard, as on a midterm 35) Ruminants differ from non-ruminants in the way they make lipids, because they lack a) citrate synthase b) acetyl-coa carboxylase c) fatty acyl synthetase d) citrate lyase 36) The major lipogenic substrate for non-ruminants is a) acetate b) lactate c) glycerol d) glucose e) amino acids

6 37) The major lipogenic substrate for ruminants is a) acetate b) lactate c) glycerol d) glucose e) amino acids 38) Protein turnover refers to a) recycling of nitrogen to and from the GI tract b) re-utilization of enzymes to catalyze many reactions c) changes in conformation, as in muscle contraction d) the simultaneous synthesis and degradation of body proteins e) none of the above 39) Protein turnover may account for % of total energy expenditure by animals. a) 10 b) 30 c) 60 d) 90 40) In the equation RE = a + b ME, the coefficient a represents a) the maintenance energy requirement b) the gross efficiency of growth c) the net efficiency of growth d) 1/maintenance e) 1/net efficiency 41) In the equation RE = a + b ME, the coefficient b represents a) the maintenance energy requirement b) the gross efficiency of growth c) the net efficiency of growth d) 1/maintenance e) 1/net efficiency 42) Energetically (i.e., kj RE/kJ ME), body protein gain is than fat gain. a) less efficient than b) more efficient than c) the same efficiency as 43) On a weight basis (i.e., kg gain/kg feed), lean gain is fat gain. a) less efficient than b) more efficient than c) the same efficiency as

7 44) If the genetic correlations between yearling weight (YW), marbling fat (MRB) and Warner- Bratzler shear force (WBS, an indicator of meat toughness) are as follows, what would be the likely effects of selecting for increased marbling? YW MRB WBS YW MRB WBS 0.50 a) heavier yearling weights and more tender meat b) increased marbling c) lighter yearling weights and tougher meat e) b and c 45) In the example given above, would show the most rapid response to selection. a) Warner-Bratzler shear force b) yearling weight c) marbling score d) none of the above 46) The following is most highly correlated (positive or negative) with meat tenderness a) intramuscular fat b) intramuscular protein c) calpain activity d) calpastatin activity 47) Genetic selection for rapid lean tissue growth tends to produce animals with a) reduced rates of protein degradation b) increased rates of protein synthesis c) unchanged rates of protein synthesis e) a and c 48) Genetic selection for rapid lean tissue growth tends to produce animals that are a) smaller at maturity b) larger at maturity c) the same size but leaner at maturity 49) Compensatory growth a) occurs during re-feeding after nutritional restriction b) Includes faster gains c) includes more efficient gains d) is due to increased appetite

8 50) The following amino acid is not essential for growth because it is not used for protein synthesis: a) lysine b) methionine c) alanine d) tyrosine e) none of the above