
6. In the normal adult heart:
a) mitral valve closure occurs before tricuspid valve closure b) pulmonary valve closure occurs before aortic valve closure c) there is isometric contraction of the left ventricle after the aortic valve opens d) atrial contraction is of more importance to ventricular filling if the heart rate increases e) the aortic valve cusps are immobile during ventricular filling
7. Resistance to laminar flow in a vessel is:
a) proportional to wall thickness b) inversely proportional to the fourth power of the radius c) proportional to length d) independent of haematocrit e) proportional to the pressure drop
8. Autoregulatory mechanisms used in hypovolaemia include:
a) an increase in precapillary sphincter tone b) an increase in capillary hydrostatic pressure c) a decrease in baroreceptor activity d) stimulation of the juxtaglomerular apparatus e) an increase in angiotensin II
9. Myocardial contractility is increased by:
a) catecholamines b) an increase in heart rate c) an increase in fibre length d) an increase in parasympathetic nervous system activity e) calcium ions
10. The carotid sinuses:
a) have stretch receptors in their walls b) give afferent impulses via the glossopharyngeal nerve c) stimulate the respiratory centre d) contain chemoreceptors e) stimulate the vasomotor centre
ANSWERS
6.TFFTT 7.FTTFF 8.TTTTT 9.TTTFT 10.TTFFT
ArticleDate:20051128
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