ch. 20 quiz

Which statement is accurate?

Filtration dominates at the arterial end of a capillary bed, and is driven by hydrostatic pressure.

Gas, nutrient, and waste exchange occur between the __________ and the tissues of the body.

capillaries

Valves in veins

cause venous blood flow to go in only one direction.

Systolic blood pressure is recorded

in arteries and is the maximal pressure that is recored during ventricular contraction.

Increased cardiac output ______ the blood pressure.

increases

The force per unit area that blood places on the inside wall of a blood vessel

is called the blood pressure.

Which of the artery types contain the internal and external elastic laminae?

muscular arteries

Blood colloid osmotic pressure is largely due to

the proteins in the blood, and it promotes reabsorption.

To prevent excessive blood loss following tissue damage, local chemicals such as

thromboxanes are released to trigger vasoconstriction

Blood hydrostatic pressure in systemic capillaries is greater than interstitial fluid hydrostatic pressure.

true

Concerning the exchange between blood and interstitial fluid at systemic capillaries, more fluid is filtered than reabsorbed.

true

The ________ is composed of an endothelium and a subendothelial layer made up of a thin layer of areolar connective tissue.

tunica initima

The ________ is composed of circularly arranged layers of smooth muscle cells

tunica media

An increase in blood vessel diameter would lead to a decrease in blood flow.

false

A portal system

blood flows through two consecutive capillary networks before returning to the heart

Precapillary sphincters will

control blood flow into the true capillaries. cause blood to flow directly from the metarteriole into the postcapillary venule. open when the tissue needs nutrients.

As blood moves from the arterial end to the venous end of a capillary, net filtration pressure

decreases, as blood hydrostatic pressure decreases.

The largest arteries of the body are classified as

elastic arteries

As a venous pathway moves closer to the heart, the veins

get larger

As an arterial pathway moves farther from the heart, the arteries

get smaller

Considering the bulk flow that occurs at capillary beds, the lymphatic system is needed to

reabsorb excess fluid from the interstitial fluid.

The velocity of blood flow through capillaries is

slow, which allows sufficient time for exchange of gases and nutrients between blood and tissues.

Which part of the circulatory system holds the largest amount of blood?

systemic veins

A network of small arteries called the ___________ provides a blood supply to the tunica externa of very large vessels.

vasa vasorum

Blood pressure is lowest in

veins