The Blood Vessels

Why does exercise increase venous return?

The heart beats faster and harder increasing cardiac output and pressure.

Why do fluids leave the capillaries at the arterial end?

The net filtration pressure of the blood is higher at the arterial end than it is at the venous end

Aid in venous return: (4)

The pressure gradient The skeletal muscle pump Gravity The thoracic (respiratory) pump

What is/are the physiological purposes of vasoreflexes?

To cause a generalized raising or lowering of blood pressure throughout the body and to selectively modify the perfusion of a particular organ by rerouting blood from one region of the body to another

The action potential from the brain to the heart travels along which nerve?

Vagus nerve

Which of the following does not aid in venous return?

Venule suction

T or F? The net osmotic pressure is equal at both the arterial and the venous ends of the capillary.

true

Where are baroreceptors found?

Carotid sinuses

Which of the following is not a mechanism that assists venous return?

Central venous pressure being greater than pressure in the venules

How do materials get from the blood to the surrounding tissues? (3)

Diffusion filtration and absorption transcytosis

T or F? Heart rate and stroke volume decrease with a decrease in parasympathetic stimulation.

False!

T or F? Increased sympathetic stimulation causes vasodilation, bringing elevated blood pressure back to normal.

False!

Action potentials are conducted from the baroreceptors to the brain via which nerve?

Glossopharyngeal nerve

Where are arterial anastomoses, in which two arteries merge, found?

In the coronary circulation

Approximately what percent of fluid that exits the capillaries at the arterial end reenters the capillaries at the venous end?

90%