Top 550+ Solved Physiology MCQ Questions Answer

a. thick filaments consist of myosin

b. actin forms a double helix

c. thin filaments include tropomyosin

d. troponin-I inhibits interaction between actin and myosin

e. T-system lies at Z-lines

a. B

b. A-delta

c. A-beta

d. A-gamma

e. C

a. does not involve calcium ions

b. after-depolarisation commences when repolarisation is 70% complete

c. total number of ions involved is minute compared to the total number present

d. spike potential peaks at sodium equilibrium potential

e. firing level (threshold) is at about -55mV

a. A-alpha

b. A-gamma

c. A-delta

d. B

e. C

a. tetrodotoxin is a sodium channel blocker

b. tetraethylammonium is a potassium channel blocker

c. tetanospasmin interferes with GABA release

d. botulinum toxin blocks release of acetylcholine

e. latrotoxin causes explosive release of acetylcholine

a. the total volume of CSF is 300mL

b. CSF is absorbed through the choroid plexus

c. the average CSF pressure is 220m-CSF

d. CSF has a higher pH than plasma

e. it contains very low levels of cholesterol relative to plasma

a. Ca2+

b. K+

c. Na+

d. PCO2

e. glucose

a. maternal artery

b. maternal vein

c. uterine vein

d. umbilical vein

e. umbilical artery

a. diastolic BP increases more than systolic BP

b. regional blood flow to the brain doubles

c. cardiac output may increase 15-fold

d. after exercise, BP takes longer to return to normal than heart rate

e. O2 consumption of skeletal muscle may increase 100-fold

a. causes a decrease in atrial pressure

b. causes the ‘A’ wave of the jugular pulse

c. causes the ‘C’ wave of the jugular pulse

d. causes the ‘V’ wave of the jugular pulse

e. causes the dicrotic notch of the aortic pulse

a. a slow depolarisation, a plateau then a rapid repolarisation

b. initial depolarisation due to a slow Na+ influx

c. repolarisation due to K+ efflux through two types of K+ channels

d. a plateau phase due to slowly opening Na+ channels

e. calcium efflux during the plateau phase

a. all cardiac cells have the same resting membrane potential

b. cholinergic fibres act predominantly by blocking tonic sympathetic input

c. discharge rates of pacemaker tissue does not change significantly with temperature

d. the bundle of HIS is not the most rapidly conducting part of the conducting system

e. the last parts of myocardium to depolarise normally do not include the septum

a. delayed repolarisation early on

b. delayed depolarisation

c. increased resting membrane potential

d. TQ segment elevation

e. current flow away from the infarct

a. total volume is approximately 55% of the total vascular volume

b. compliance approximately 25 times the arterial side

c. total volume of venules is twice the total capillary volume

d. valves in the cerebral circulation

e. substantial venoconstriction in response to noradrenaline

a. serotonin

b. ANP

c. NO

d. K+

e. histamine