Crowdly

resistance to blood flow is highest in the

capillaries.

capillaries are the narrowest vessels.

substance exchange reduces flow velocity.

capillaries

represent the greatest cross-sectional area of the circulation.

Which of the following does NOT affect the rate of substance diffusion across the capillary wall? (Lecture 7)

Concentration gradient of the substance across the capillary wall.

Capillary wall permeability to the substance.

Capillary surface area.

Molecular size of the substance.

Blood pressure in the capillary.

Which ONE of the following statements is CORRECT

? During

dynamic / aerobic exercise, (Lecture 7)

mean arterial pressure decreases significantly.

diastolic blood pressure increases more than

systolic.

pulse pressure is reduced.

total

peripheral resistance to blood flow decreases.

vasodilation occurs in the visceral organs.

If a person’s systolic blood pressure is 120 mmHg, and their diastolic blood pressure is 80 mmHg, then their pulse pressure is: (Lecture 5)

120 mmHg

100 mmHg

40 mmHg

80 mmHg

93 mmHg

Which ONE

of the following blood vessel types has the highest

compliance, enabling them to function as capacitance vessels? (Lecture 5)

large arteries

aorta

capillaries.

resistance arterioles.

veins.

When cardiac output is measured using the Fick principle: (Lecture 4)

the subject does not need to be in ‘steady state’.

a six-fold increase in oxygen uptake mean six-fold increase in cardiac output.

cardiac catheterization is not necessary.

cardiac output (CO) is calculated as pulmonary oxygen uptake (U) multiplied by the difference in oxygen content between arterial

blood (A) and mixed venous blood (V); CO = U(A-V).

pulmonary blood flow is equated with cardiac output.

Which ONE of the following is INCORRECT

regarding the effect of

sympathetic nerve stimulation on the cardiovascular system? (Lecture 6)

Causes vasoconstriction.

Stimulates tachycardia.

Increases arterial blood pressure.

Increases cardiac output.

Constricts

capillaries.

Unlike blood vessels, the lymphatic system: (Lecture 7)

has capillaries which connect arteries and veins.

reabsorbs protein and foreign particles from the interstitial fluid.

forms a filtrate which eventually becomes urine.

removes damaged erythrocytes from the circulation.

has a role in controlling blood pressure.

Blood flow in a vessel is equal to the pressure gradient across the

length of the vessel (inflow – outflow pressure), divided by the resistance to

flow (Q = ΔP/R). Which

ONE

of the following statements regarding this

relationship is

CORRECT? (Lecture 5)

The relationship does not apply to capillaries, as they are so narrow.

The relationship applies equally to laminar and turbulent flow.

Flow is increased by increasing the length of the

vessel.

Resistance to flow is independent of the diameter of the conducting vessel.

If outflow pressure is doubled with no change in inflow pressure, flow will be reduced.

The arterial baroreceptor reflex:

causes an

increase in heart rate on moving from lying down to standing.

is important for long-term control of blood

pressure.

increases systemic arterial blood pressure.

is mediated by special pressure receptors in the abdominal

aorta.

is an example of a positive feedback control system.