APHY 201 Exam 3 Review copy PDF

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Review for exam 3, questions with answers....

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APHY 201 Exam 3 Chapters 12 14 15 REVIEW

1) The origin is the end of the skeletal muscle that attaches to the - More stationary bone. 2) The function of transverse tubules is to- (also called T Tubules)- Allow action potentials to move rapidly from the cell surface into the interior of the fiber so that they reach the terminal cistern simultaneously. 3) Most of the time, the parallel thick and thin filaments of the myofibrils are connected by ________ that span the space between myosin and actin molecules. - Crossbridges. 4) The function of the titin protein is to -Stabilize the position of the contractile filaments and returns the elasticity of muscles to their resting length. 5) When a skeletal muscle cell contracts and the muscle shortens, - Some myosin heads are forming cross bridges as others are releasing them. 6) As ATP binds to the myosin head at the beginning of a muscle contraction cycle, the myosin head immediately- Detaches from actin. 7) The binding of acetylcholine to its receptor at the neuromuscular junction causes the opening of a- Channel for both Na+ and K+. 8) During heavy exercise, the ATP requirements of active muscle are likely to be met by metabolism of- Carbohydrates. 9) Muscle fatigue arises primarily from failure in- Excitation-contraction coupling. 10) Which of the following is a characteristic of slow-twitch oxidative skeletal muscle fibers?Long contraction duration and high capillary density. 11) When comparing complete tetanus with unfused (incomplete) tetanus, which is true?Complete tetanus involves development of maximum tension. 12) A motor unit consists of- One neuron and all the skeletal muscle fibers it controls. 13) Motor units that control skeletal muscles involved with fine motor movements (eye muscles or the hands) have ________ muscle fibers than motor units that control more gross movements (gastrocnemius muscle of the lower leg).- Fewer muscle fibers. 14) The nervous system avoids muscle fatigue during submaximal contraction by- Asynchronous recruitment. 15) Compared to skeletal muscle, contraction of smooth muscle cells is16) Put these events in the correct chronological sequence: 1-Acetylcholine binds to receptors on the motor end plate. 2-End-plate potentials trigger action potentials. 3- Transverse tubules convey potentials into the interior of the cell. 4- Ca2+is released from the sarcoplasmic reticulum. (3,1,2,4). 1. End-plate potentials trigger action potentials. 2. Transverse tubules convey potentials into the interior of the cell. 3. Acetylcholine binds to receptors on the motor end plate. 4. Ca2+ is released from the sarcoplasmic reticulum. 17) After death, when metabolism stops, in which step of the contractile cycle must skeletal muscles remain?- The rigor state. 18) Skeletal muscle fibers with the greatest endurance rely on ________ for energy.- Oxidative phosphorylation.

19) The most accurate definition of artery is a vessel that- Carries blood away from the heart. 20) The driving force for blood flow is a(n) ________ gradient. - Pressure. 21) Each of the following changes will result in increased blood flow to a tissue except one. Identify the exception. - Decreased vessel diameter. 22) As blood vessel length increases, - Surface area increases. 23) The function of the pericardial fluid is to - Lubricate the external surface of the heart to prevent friction. 24) The term myogenic indicates that the heart muscle is the source of - Source of the electrical signal that triggers heart contraction. 25) Stretching a myocardial cell - Causes more Ca2+ to enter and increases the force of contraction. 26) The importance of the plateau phase of the action potential of myocardial cells is inPreventing tetanus. 27) Auto-rhythmic cells - Are cardiac cells that spontaneously and rhythmically depolarize and fire action potentials. 28) The depolarization of the pacemaker action potential spreads to adjacent cells through - Gap junctions. 29) The AV node is important because it - Directs impulses from the atria to the ventricles and delays the transmission of the electrical impulses to the ventricles in order for the atria to finish contracting. 30) The medical term for heart attack is - Myocardial infarction. 31) When the heart is in fibrillation- Effective pumping of the ventricles ceases (comes to an end) because the myocardial cells fail to work as a team, and the brain cannot get adequate oxygen. 32) ECGs - (Electrocardiogram) - Record the summed electrical events of the cardiac cycle. 33) Which event happens at the start of a cardiac cycle? - The SA node fires. 34) Which of the following events result in the first heart sound? - The closing of the AV valves. 35) The term used to describe the amount of blood in the ventricle available to be pumped out of the heart during the next contraction is - End diastolic volume (EDV). 36) The volume of blood ejected from each ventricle during a contraction is called the - Cardiac output. 37) Which of these will increase the heart rate? 38) Drugs known as beta blockers will - Reduce heart rate and blood pressure. 39) Which of the following conditions would have the greatest effect on peripheral resistance? Doubling the diameter of the vessel. 40) If a myocardial infarction results in the formation of scar tissue along the pathway of the left bundle branch- Cardiac arrhythmia may occur. Which is an irregular heartbeat caused by too slow heart rate or too fast. 41) Drugs known as calcium channel blockers can be used to - Decrease the force of cardiac contraction. 42) Perfusion is- Blood flow to lung tissues. 43) The only blood vessels whose walls permit exchange between the blood and the surrounding interstitial fluids are the - Venules and capillaries.

44) Angiogenesis is - The development of new blood vessels. 45) The mean arterial pressure (MAP) is important because - It represents the driving pressure for blood flow. 46) Blood flow to a tissue will increase - If the level of carbon dioxide at the tissue increases. 47) The difference between the systolic and diastolic pressures is called the - Pulse pressure. 48) All of the following would cause an increase in blood pressure EXCEPT -?? 49) Each of the following paracrines may cause vasodilation EXCEPT - Ca2+. 50) The elevated blood pressure that sometimes accompanies pregnancy is known as- Preeclampsia....