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Are you a rad-enough dude to receive 100% on this thing?
As a joke, take a look at one of the midterms from the previous year (our class took one of the same quality and difficulty) for the Physiology course I took this past semester.
Directions: For all questions, choose the most INCORRECT answer.
1)Peripheral nervous system:
a)The somatomotor system releases ACh peripherally and innervates striated muscle.
b)The somatomotor system and autonomic postganglionic parasympathetic system release neurotransmitters that bind to nicotinic ACh receptors.
c)The peripheral sympathetic neuron releases the neurotransmitter norepinephrine.
d)The peripheral parasympathetic postganglionic neuron releases the same neurotransmitter that a motor neuron axon terminal releases at the neuromuscular junction.
2)Neuromuscular junction:
a)The end-plate potential is a suprathreshold, graded potential resulting from the opening of non-specific cation channels.
b)If voltage-gated Ca++ channels open in the presynaptic terminal membrane in response to invasion by an action potential, the subsequent influx of Na+ into a skeletal muscle cell in the end-plate region is sufficient to cause opening of voltage-gated Na+ channels in the sarcolemma.
c)ACh released at the neuromuscular junction binds to a ligand-gated channel that increases the permeability of a skeletal muscle cell membrane in the end-plate region to K+ ion.
d)The opening of voltage-gated Na+ and K+ channels in the end-plate membrane leads to action potential propagation along t-tubule membranes.
3)Skeletal muscle anatomy:
a)A sarcomere contains the proteins troponin, tropomyosin, titin and myosin.
b)The A band contains non-overlapping, multiple myosin and actin filaments.
c)The striations observed in a single muscle fiber are due to the presence of multiple sarcomeres.
d) Myofibrils are composed of thick and thin filaments organized into sarcomeres.
4)Skeletal muscle:
a)Recycling of cross-bridges requires the binding of ATP to myosin.
b)ATP is necessary for the shortening and lengthening of sarcomeres during contraction and relaxation of skeletal muscle fibers.
c)The entrance of Ca++ ions through the opening of modified voltage-gated Ca++ channels in the t-tubule membrane is, in part, responsible for the release of Ca++ from the SR.
d)Upon the completion of the power stroke, the chemical energy of ATP has been transformed into the mechanical energy of contraction.
5)Relationship between electrical and mechanical events in skeletal muscle contraction:
a)It is uncommon to observe cross-bridge cycling in the absence of tension development during a single twitch contraction.
b)A skeletal muscle fiber can sustain its maximum tension while sarcomere lengths remain constant.
c)For all practical purposes, the refractory period for action potentials propagating along the t-tubule system is not a limiting factor for maximizing temporal summation of tension.
d)An individual muscle fiber is innervated by one motor unit, but one motor unit innervates multiple muscle fibers.
6)Heart facts:
a)Despite the fact that left ventricular muscle mass is greater than right ventricular muscle mass, each ventricle ejects the same stroke volume during each cardiac cycle.
b)The mitral and tricuspid valves open and close at approximately the same times during each cardiac cycle
c)Venous return to the right atrium equals cardiac output to the entire systemic circulation.
d)The volume of blood pumped into the ventricles during atrial systole accounts for approximately 40% of the end-diastolic blood volume in each ventricle.
7)Coordination of heart beat:
a)The pacemaker potential in SA nodal cells is an autorhythmic graded potential generated by a net influx of Na+ ions.
b)A differentiating feature of cardiac vs. skeletal muscle is that the rising phase of the action potential for cells of the cardiac conducting system and for cardiac muscle cells requires opening of voltage-gated Ca++ channels, and this does not occur in skeletal muscle cells.
c)The threshold depolarizing graded potential necessary for the firing of action potentials in ventricular muscle cells is generated by the intercellular movement of Ca++ and Na+ through gap junctions.
d)The conducting system insures the near simultaneous contraction of right and left atria followed by the near simultaneous contraction of the right and left ventricles.
8)Electrocardiogram:
a)The P wave precedes atrial systole.
b)The T wave occurs during atrial diastole.
c)A prolongation of the time between R wave peaks in an ECG recording could be associated with an increase in heart rate.
d)The QRS complex wave begins before ventricular isovolumetric contraction.
9)Cardiac output (all variables not mentioned are held constant):
a)A sustained increase in venous return via the superior and inferior vena cavae will lead to an increase in cardiac output.
b)Activation of muscarinic receptors on SA node cells will decrease cardiac output.
c)Increasing the slope of the pacemaker potential in SA node cells will increase cardiac output.
d)Given normal values for resting heart rate and stroke volume, increasing stroke volume by 16% and decreasing arteriolar diameter by 2% will result in no change in cardiac output.
10)Mean arterial blood pressure (all variables not mentioned are held constant):
a)If pulse pressure increases but mean arterial blood pressure remains constant, then diastolic pressure has decreased.
b)Decreasing arteriolar radius by 50% will decrease mean arterial pressure 16 fold.
c)If one had a tumor in the adrenal medulla that continually released epinephrine, mean arterial blood pressure would increase due to increases in heart rate.
d)A sustained increase in end-diastolic volume will increase mean arterial blood pressure.
11)Control of heart rate:
a)A denervated heart rate in humans will be ≈ 100 beats/min.
b)NE released by sympathetic cardiac nerve fibers will cause the pacemaker potential in SA nodal cell to increase in slope.
c)Inhibition of parasympathetic cardiac nerve action potential activity will lead to a decrease in the slope of SA nodal cell pacemaker potentials.
d)The resting heart rate in humans suggests that parasympathetic cardiac nerve activity is tonically active.
12)Capillary bulk flow:
a)In a capillary bed in the systemic circulation, filtration normally exceeds absorption.
b)Increasing the rate of facilitated diffusion of glucose into skeletal muscle cells will not affect the rates of capillary filtration and absorption in skeletal muscle.
c)In the systemic circulation, if blood pressure at the arterial end of systemic capillaries remained constant and the blood pressure on the venule end of the capillaries increased, you would anticipate that excess fluid filtration would exceed 2-3 L/ day.
d)If the osmotic pressure exerted by proteins in the pulmonary circulation decreased, capillary filtration would decrease.
13)Short term regulation of arterial blood pressure:
a)Baroreceptor nerve fiber activity is inhibited when MAP decreases.
b)An increase in MAP will increase parasympathetic cardiac nerve activity.
c)A decrease in MAP will increase sympathetic vasomotor nerve activity.
d)At a normal resting value of MAP, baroreceptor action potential frequency is > 0.
14)Orthostasis and orthostatic hypotension:
a)Orthostatic hypotension is initiated by the force of gravity on the systemic circulation.
b)The initial drop in MAP is associated with a decrease in cardiac output.
c)The baroreceptor reflex response to orthostatic hypotension includes activation of sympathetic vasomotor fibers and an increase in stroke volume.
d)The initial decrease in MAP during orthostasis is the result of an increase in parasympathetic cardiac nerve activity and a concomitant decrease in sympathetic cardiac nerve activity.
15)Innate immune pathways for the destruction of viruses:
a)Viral reproduction requires intracellular assembly in a non-viral host cell.
b)Natural killer cells are lymphocytes that induce viral apoptosis when they bind specifically to surface receptors located on viral membranes.
c)Synthesis and exocytosis of interferon protein is a non-specific host cell response to infection by a virus.
d)Non-virally infected cells respond to interferon binding to interferon receptors by synthesizing antiviral proteins that non-specifically block intracellular viral replication.
16)Humoral immunity:
a)B cell receptors are essentially antibodies in which the heavy chain stem region has been modified to allow for insertion and anchoring in B cell membranes.
b)Immunocompetent B lymphocytes are found in bone marrow and lymph nodes.
c)Plasma cells synthesize and secrete antibodies that specifically recognize the antigens that initially activated their B cell progenitors.
d)Before B cells proliferate (clonal selection) and differentiate into memory and plasma cells, progenitor lymphoid B stem cells in bone marrow are antigen-activated.
17)Immune defenses:
a)Humoral immune responses are adaptive and require activation of B and cytotoxic T lymphocytes.
b)Innate pathways are present at birth and do not typically exhibit specificity and memory.
c)Phagocytosis is a critical defense mechanism that is receptor-mediated.
d)Acquired (adaptive) immune responses exhibit specificity and memory.
18)Cell-mediated immunity:
a)Cytokines secreted by activated T helper cells help activate B cells and cytotoxic T cells.
b)T helper cell receptor binding to an antigen-MHC II complex presented by an APC cell is only one necessary condition for T helper cell activation and proliferation.
c)Since T helper cells do not directly kill infected cells or directly destroy antigens, a pathogen that reduces significantly the numbers of T helper cells would not likely be life-threatening.
d)Membrane surface antigen recognition by T helper cells requires that the antigen be intracellularly complexed with a major histocompatibility complex protein unique to every individual.
19)Acquired immune responses to viral antigens:
a)Cytotoxic T cells become immunocompetent in the thymus gland, but arise from stem cells located in bone marrow.
b)Cytotoxic T cell receptor binding to a viral antigen requires that the viral antigen be intracellularly complexed with MHC I prior to being inserted into the peripheral membrane of the infected cell.
c)Cell destruction by lysis results when activated cytotoxic T cells secrete a pore forming protein, perforin, which inserts a membrane attack complex into virally infected cell peripheral membranes.
d)Cytotoxic T cell proliferation is stimulated by the release of cytokines from T helper cells activated upon binding to virally infected APC cells.
20)HIV and AIDS:
a)HIV preferentially infects cytotoxic T helper cells.
b)Cytotoxic T cells release a protein that lyses infected T helper cells.
c)HIV is a viral infection that is asymptomatic.
d)AIDS is not a single disease by rather an acquired syndrome characterized by the collapse of the immune system.
21)Antibodies:
a)Antibodies participate in viral neutralization and opsonization.
b)While antibodies can enhance phagocytosis, they do not aid in the formation of APC macrophages.
c)Under appropriate conditions, antibodies stimulate antimicrobial proteins to form membrane attack complexes.
d)Antibodies are a critical participant in the humoral immune response to extracellular antigens.
22)Glomerular filtration:
a)Increased renal sympathetic nerve activity will decrease GFR because glomerular hydrostatic pressure decreases.
b)Myogenic autoregulation results in vascular smooth muscle contraction in response to mechanical stretch of renal afferent arterioles.
c)Tubuloglomerular autoregulation will reflexly cause glomerular hydrostatic pressure to decrease in response to an increase in GFR.
d)Increasing afferent arteriolar diameter will decrease glomerular filtration.
Do note, this is an undergraduate course at my university.
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