1 BIOL1431 - FALL 2001 SAMPLE EXAM 4 THIS SAMPLE EXAM COVERS ONLY THE MATERIAL GIVEN BY DR. DELCOUR SINCE EXAM 3. THIS DOES NOT COVER MATERIAL GIVEN BY DR.DRYER. There is only 1 correct answer. ALWAYS CHOOSE THE BEST ANSWER. If you believe that 2 or more of the choices given are correct and you are given the combination of those choices as an answering option (ex: a and b), then you should mark this answering option on your Scantron. For the following questions, choose: a) TRUE b) FALSE 1. When a sarcomere contracts, the length of individual actin filaments is decreased 2. When a sarcomere contracts, the length of individual myosin filaments is decreased 3. Rod cells fire action potentials in response to light 4. The organ of Corti is used to detect head movements 5. ATP is needed to bend a flagellum 6. The second heart sound is due to the aortic and pulmonary valves closing 7. Fetal hemoglobin releases oxygen better than maternal hemoglobin 8. Elastic tissue is found in veins but NOT in arteries 9. The velocity of blood flow is much smaller in the capillaries than in the veins 10. Ca2+ ions are not required for contraction of the heart 11. Stretch sensors located on arteries can detect fluctuation in blood pressure 12. The loop of Henle is the site for regulated reabsorption of water (i.e. in response to body needs) 13. Proteins are NOT found in the bulk flow that leaves capillaries during ultrafiltration 14. As renal fluid progresses down the descending limb of the loop of Henle, the concentration of NaCl in the renal fluid is progressively increased 15. The volume of the glomerular filtrate is always greater than the volume of urine 16. The only role of the collecting duct is to collect urine 17. Vasodilation of the afferent arteriole will lead to an increase in the glomerular filtration rate ------------------------------------------------------------------------------------------------------------ 18. Which of the following statements about the cochlea is true? a) Air vibrations are converted into fluid vibrations b) lower frequency sounds lead to vibrations of the basilar membrane closer to the oval window c) the vibration of the round window precedes the vibrations of the oval window d) the basilar membrane has the same flexibility throughout the cochlea 19. What are the semi-circular canals used for? a) Hearing b) Detection of linear accelerations c) Detection of head rotations d) Detection of gravity e) B and D2 20. When light of the appropriate wavelength hits a rod cell, … a) The membrane potential of the plasma membrane stays the same b) The membrane potential of the plasma membrane becomes more negative c) The membrane potential of the plasma membrane becomes more positive d) The membrane potential of the internal membranes becomes more negative 21. Which of the following is the correct sequence of events immediately following the stimulation of an odorant receptor by an odorant? a) activation of adenylate cyclase – activation of a G protein – activation of protein kinase A b) activation of a G protein - activation of adenylate cyclase –– activation of protein kinase A c) activation of a G protein - activation of adenylate cyclase – opening of cAMP-dependent channel d) activation of a G protein - activation of adenylate cyclase – closing of cAMP-dependent channel 22. Where are odorant receptors located? a) In the plasma membrane of an olfactory neuron b) In the cytoplasm of an olfactory neuron c) In the nucleus of an olfactory neuron 23. Which one the following structures does NOT move in response to air vibrations (directly or indirectly)? a) The eardrum b) The oval window c) The basilar membrane d) The tectorial membrane e) The round window 24. Which of the following is TRUE about hair cells of the cochlea and hair cells of the semi-circular canals? a) They are both sensitive to fluid movements b) The both have hair-like projections (cilia) embedded into a cupula c) They both fire action potentials d) They both have mechanosensors e) A and D 25. Which one of the following statements is true about contraction of striated muscles? a) It does not require an action potential in the muscle cell b) Ca2+ ions are needed to bind to myosin c) Ca2+ ions are released by the sarcoplasmic reticulum d) Neurotransmitter is released in the T tubule 26. Which protein(s) are located in the axoneme? a) tubulin b) dynein c) actin d) myosin e) A and B 27. To which protein does calcium bind to control the contraction of striated muscles? a) Actin3b) Myosin c) Troponin d) Tropomyosin 28. Which two proteins are mechanoenzymes? a) Actin and myosin b) Tubulin and dynein c) Actin and tubulin d) Myosin and dynein 29. What do mechanoenzymes do? a) they break down other proteins b) They phosphorylate other proteins c) They break down ATP d) They “do work” by changing their conformation e) C and D 30. The T tubule … a) Is found in the kidney b) Is found in striated muscles where it propagates the action potential c) Release calcium into muscles d) Releases the neurotransmitter that triggers muscle contraction 31. Myofibrils … a) are bundles of highly organized actin and myosin filaments b) are muscle cells c) are muscle fibers d) are actin filaments e) B and C 32. A cross-section of a cilium will show ….. a) no plasma membrane at all b) 9 doublets of microtubules surrounded by the plasma membrane c) microfilaments d) polymers of tubulin e) B and D 33. Most of the carbon dioxide in blood is transported… a) bound to hemoglobin b) as a dissolved gas in the plasma c) as carbonic acid d) as calcium carbonate e) as bicarbonate ion 34. Which of the following is true about hemoglobin? a) It is dissolved in blood plasma (i.e. it is a solute of blood plasma) b) It can bind CO2 c) In a healthy body, it releases about 25% of oxygen in tissues and organs d) B and C e) A and B and C4 35. Which of the following is the location of sensors sensitive to oxygen content in blood? a) hypothalamus b) brain stem c) aorta and carotid arteries d) pulmonary artery e) pulmonary vein 36. Below is the equation that governs the diffusion of a gas Q = D x A x [(C1-C2)/ L] How do animals keep the concentration of gas C2 as low as possible? a) By removing oxygenated blood from the