BIOL 252 Practice Exam 2 KEY 1 In response to a decrease in blood pressure the kidneys decrease urine production a ADH secretion increases b c blood volume increases d all of the above e b and c are correct 2 Yellow bone marrow contains a large percentage of a Fat b Hematopoietic cells c Elastic tissue d Periosteum a Osteocyte b Osteoblast c Osteoclast d Chondrocyte 3 The cell responsible for secreting the matrix of bone is the 4 In skeletal muscle cell contraction calcium acts to Increase the action potential transmitted along the sarcolemma a b Release the inhibition on Z discs c Remove the blocking action of tropomyosin d Cause ATP to bind to actin 5 The poison curare competes with acetylcholine ACh for receptor sites in muscles but unlike Ach binding of curare to the receptors does not result in any effect in the corresponding muscle sarcolemma What is the possible medical use for curare a Curare can be used to slow a rapid heartbeat b Curare can be used to treat Myasthenia gravis c Curare can be used to prevent muscle spasms in some neurological disorders d All of the above 6 In a series of unfortunate events the action filaments in a sarcomere moved away from the myosin filaments and now they are no longer able to connect they no longer overlap What happened to the A band and the H band a The A band remained the same while the H band became longer b The A band is nonexistent but the A band is longer c The A band is nonexistent but the H band is shorter d Both the A band and the H band remained the same 7 One of the reasons corpses usually exhibit rigor mortis is because a ATP is required for myosin heads to attach to actin b ATP is required for myosin heads to detach from actin c Calcium stores become deficient d Corpses are non living humans 8 Some oxygen may be stored within muscle fibers bonded to the protein creatine a True b False BIOL 252 Practice Exam 2 KEY 9 Osteocytes divide as a response to growth hormone signaling 10 Collagen fibers are the major components of the ground substance in connective 11 The M line of a sarcomere is composed of thick filaments 12 The myosin head binds to the filamentous actin only when it is in the its high energy a True b False tissues a True b False a True b False configuration a True b False 13 During an isotonic concentric muscle contraction how many of the following regions of sarcomeres shorten I zone H zone Distance between Z discs A band A B C D E 0 of the above will shorten 1 of the above will shorten 2 of the above will shorten 3 of the above will shorten 4 of the above will shorten 14 Imagine you create a muscle composed of muscle cells with the normal organelles present in muscle cells but in a different arrangement These muscle cells have a sarcolemma but no t tubules Directly inside the sarcolemma are a row of mitochondria and then inside that is a layer of all the myofibrils The sarcoplasmic reticulum is at the very center of the cell Assuming these cells express the usual muscle cell proteins and have normal neuromuscular junctions what would you expect to happen in terms of muscle contraction when a stimulus occurs a Muscle tension would occur but it would be delayed since it would take longer for the calcium to be released from the sarcoplasmic reticulum and bind to tropomyosin opening up the myosin binding sites on actin b Less muscle tension would occur since the sarcoplasmic reticulum is only contracting the inner layer of myofibrils so only they would contract c No muscle tension would occur since calcium would not be released from the sarcoplasmic reticulum d More muscle tension would occur since the layer of mitochondria around the outside of the cell would produce high amounts of ATP BIOL 252 Practice Exam 2 KEY 15 During isometric contraction what occurs within the body a The muscle organ changes size shortens OR lengthens b Within an individual cell some of the sarcomeres with a myofibril shorten but not all c The elastic components of the muscle organ are elongated d B and C 16 Which of the following exercises would result in the highest sustained muscle tension a Holding plank position b Walking uphill c Bicep curls with a 20lb dumbbell d Running uphill 17 During muscle contraction how many of these processes require ATP Transport of calcium ions from the sarcoplasmic reticulum into the cytoplasm Transport of calcium ions from the ECF into the axon terminal of the neuron at the neuromuscular junction following the firing of an action potential in that neuron Opening of acetylcholine gated sodium channels Opening of voltage gated sodium channels on the muscle cells A None require ATP B One requires ATP C Two require ATP D Three require ATP E All of the above require ATP 18 Which individual would be the lowest risk for developing osteoporosis a A 54 year old woman who smokes b A 54 year old male endurance runner who only eats beef jerky c A 47 year old female competitive swimmer who meditates regularly d A 51 year old male yogurt enthusiast who hikes regularly 19 If you found a patient who lacked bone marrow in their bones you d expect that they would be deficient in which of the following a Plasma the fluid component of blood b White blood cells c Osteoclasts d Chondrocytes e A and B f All of the above 20 In response to an increase in mean arterial pressure the baroreceptor reflex causes a an increase in sympathetic nervous system activity b a decrease in peripheral resistance c vasoconstriction d an increase in cardiac output e all of the above 21 Unless otherwise noted the term blood pressure refers to the blood pressure BIOL 252 Practice Exam 2 KEY in the small distributing arteries a b summed up by all the blood pressures in the systemic circulation c diastolic pressure systolic pressure 2 d in the largest arteries near the heart 22 An increase in peripheral resistance would have what effect on blood pressure a no effect b increase c decrease d varies from person to person 23 The blood pressure in the arterioles entering the tissues is lower than the one in the large arteries because a we are losing blood to the tissues and blood volume contributes to pressure b c d both b and c are correct the longer the blood travels the more friction it encounters the arteriole are less elastic than the arteries 25 While the semilunar valves are open during a normal cardiac cycle the pressure in the 24 Increased venous return results in a increased stroke volume b decreased ESV c decreased heart rate d both a and b