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2.3 Heart as a Pump — Test 1
Q1. In exercising skeletal muscle, the major increase in blood flow is due to:✓ Local metabolic vasodilation
Q2. Blood pressure is highest in the:✓ Systemic arteries (aorta)
Q3. Deoxygenated blood is carried by the:✓ Pulmonary artery
Q4. The blood vessel that connects the pulmonary artery to the aorta in the foetus and closes after birth is the:✓ Ductus arteriosus
Q5. The largest blood vessel in the human body is the:✓ Aorta
Q6. The Frank–Starling law of the heart relates to the contraction and relaxation of the:✓ Heart
Q7. A top athlete has a resting heart rate of 50 beats/min and a cardiac output of 5 litres/min. The stroke volume is:✓ 100 mL
Q8. Who is credited with discovering the circulation of blood?✓ William Harvey
Q9. Arrhythmia is an abnormality in the:✓ Heartbeat (rhythm)
Q10. The heart is located within the thoracic cavity in the region called the:✓ Mediastinum
Q11. The main determinant of cardiac output, and hence a key factor in blood pressure, is:✓ Cardiac output (heart rate × stroke volume)
Q12. The hepatic portal system carries blood from the:✓ Gut (intestines) to the liver
2.3 Heart as a Pump — Test 2
Q13. Nitric oxide (NO) lowers blood pressure by:✓ Relaxing vascular smooth muscle (vasodilation)
Q14. The endothelial enzyme that produces the vasodilator nitric oxide is:✓ Endothelial nitric oxide synthase (eNOS)
Q15. Which of the following is NOT a vasoconstrictor?✓ Prostacyclin
Q16. Stimulation of arterial baroreceptors (e.g. by raised blood pressure) leads to:✓ Bradycardia and a fall in blood pressure
Q17. Autoregulation of blood flow in an active tissue is achieved locally mainly by:✓ Accumulated metabolites causing vasodilation
Q18. The 'respiratory waves' (slow 4–6 mmHg oscillations) in arterial pressure are linked to:✓ The breathing cycle (inspiration and expiration)
Q19. Cyclic GMP (cGMP), the second messenger for nitric-oxide-mediated vasodilation, is produced from GTP by:✓ Guanylate cyclase
Q20. In a closed circulatory system (as in vertebrates), blood:✓ Always stays within vessels
Q21. An open vascular (circulatory) system is typically found in:✓ Crabs (and most arthropods)
Q22. Stroke volume of the heart is defined as:✓ The volume of blood ejected by a ventricle per beat
Q23. Capillaries are well suited for the exchange of materials because they:✓ Have very thin (single-cell) walls and a large total surface area
Q24. Peripheral (vascular) resistance is determined chiefly by the:✓ Radius of the arterioles
2.3 Heart as a Pump — Test 3
Q25. Veins return blood to the heart against gravity with the help of:✓ One-way valves and the skeletal muscle pump
Q26. During strenuous exercise, cardiac output rises mainly because of an increase in:✓ Both heart rate and stroke volume
Q27. Systolic blood pressure refers to the pressure in the arteries during:✓ Ventricular contraction
Q28. The pressure difference that drives blood through the systemic circulation is greatest between the:✓ Aorta and the venae cavae
Q29. Angiotensin II raises blood pressure by:✓ Constricting arterioles and stimulating aldosterone release
Q30. Endothelin, secreted by vascular endothelium, acts to:✓ Constrict blood vessels (raise pressure)
Q31. Pulse pressure is defined as:✓ The difference between systolic and diastolic pressure
Q32. The systemic circulation differs from the pulmonary circulation in that it:✓ Operates at higher pressure and supplies the whole body
Q33. The mean arterial pressure (MAP) is best estimated as:✓ Diastolic pressure plus one-third of the pulse pressure
Q34. A fall in blood pressure is rapidly corrected by the baroreceptor reflex, which causes:✓ Increased heart rate and vasoconstriction
Q35. The capillary endothelium normally secretes all of the following EXCEPT (which is NOT an endothelial product):✓ Guanosine
Q36. The pulmonary artery is unusual among arteries because it carries:✓ Deoxygenated blood (to the lungs)
2.3 Heart as a Pump — Test 4
Q37. The major artery carrying oxygenated blood from the left ventricle to the body is the:✓ Aorta
Q38. Blood returns to the right atrium of the heart through the:✓ Venae cavae (superior and inferior)
Q39. Capillaries are the site of exchange because their walls are:✓ A single cell thick, allowing easy diffusion
Q40. Arteries differ from veins in that arteries:✓ Have thicker, more muscular and elastic walls
Q41. Veins contain valves to:✓ Prevent the backflow of blood
Q42. The contraction phase of the heart, when blood is pumped out, is called:✓ Systole
Q43. During diastole, the heart:✓ Relaxes and fills with blood
Q44. A normal resting blood pressure in a healthy adult is about:✓ 120/80 mmHg
Q45. Hypertension means a blood pressure that is:✓ Persistently higher than normal
Q46. The instrument used to measure blood pressure is the:✓ Sphygmomanometer
Q47. The pulse felt at the wrist results from:✓ The pressure wave of each ventricular contraction
Q48. Atherosclerosis, a narrowing of arteries, is caused mainly by:✓ Build-up of fatty plaques in the artery wall
2.3 Heart as a Pump — Test 5
Q49. A heart attack (myocardial infarction) usually results from:✓ Blockage of a coronary artery
Q50. The double circulation of mammals means that blood:✓ Passes through the heart twice per complete circuit
Q51. The lymphatic system returns excess tissue fluid to the:✓ Bloodstream (via large veins near the heart)
Q52. The smallest blood vessels, where exchange with tissues occurs, are the:✓ Capillaries
Q53. Blood flow to an organ can be increased by:✓ Vasodilation of its supplying arterioles
Q54. The heart's own muscle is supplied with blood by the:✓ Coronary arteries
Q55. During exercise, blood is preferentially redirected toward the:✓ Working skeletal muscles
Q56. The pressure in the arteries during ventricular relaxation is the:✓ Diastolic pressure
Q57. Anaemia can reduce the oxygen-carrying capacity of blood and lead the heart to:✓ Beat faster to compensate
Q58. The fish heart has two chambers and pumps:✓ Only deoxygenated blood (single circulation)
Q59. The walls of the left ventricle are thicker than those of the right ventricle because the left ventricle:✓ Pumps blood to the whole body at higher pressure