A&P II Chapter 20 Assignment

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

decreases, as blood hydrostatic pressure decreases.

A venule becomes a vein when its diameter is greater than ________ micrometers.

100

If someone's blood pressure were listed as 125/75 mmHg, then their pulse pressure would be

50 mmHg.

If someone's blood pressure were listed as 110/65 mmHg, then their mean arterial pressure (MAP) would be

80 mmHg.

Imagine yourself sitting in an awkward position in an uncomfortable chair that is depriving part of your leg from normal blood flow. This deprivation of adequate perfusion will result in what sort of local changes in your leg?

Buildup of carbon dioxide and hydrogen ions will cause vasodilation.

Oxygen and carbon dioxide are transported between the blood and interstitial fluid by way of

diffusion from areas of higher concentration to lower concentration.

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.

Precapillary sphincters will

close when the tissue's needs have been met.

Blood flow is

directly related to the pressure gradient but inversely related to the resistance.

Peripheral resistance is

directly related to vessel length and inversely related to vessel radius.

The function of the postcapillary venule is to

drain the capillary bed.

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

Systolic blood pressure is recorded

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

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

reabsorb excess fluid from the interstitial fluid.

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

tunica intima

In arteries, the thickest layer of the wall is the

tunica media

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

tunica media

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

vasa vasorum

When physical exertion has ended and the body is at rest, veins demonstrate

vasodilation so that blood is shifted toward the rest of the circulatory system.

Blood pressure is lowest in

veins

Which is the most common type of capillary?

Continuous

Which statement is accurate?

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

Which statement accurately compares filtration and reabsorption?

Filtration involves bulk flow of fluid out of the blood, whereas reabsorption is bulk flow back into the blood.

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

Muscular arteries

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

Systemic veins

Which statement accurately describes total blood flow?

Total blood flow equals cardiac output and can vary significantly over time with activity levels.

Tendons and ligaments have

a low degree of vascularization, therefore low perfusion and slow healing.

Sinusoids are found in a: bone marrow b: spleen c: small intestine d: kidney e: liver f: muscle g: skin

a, b, e

Which are found in the capillary wall? a: Endothelium b: Subendothelial layer c: Internal elastic lamina d: Intercellular clefts e: External elastic lamina f: Basement membrane

a, d, f

If someone suffered from hypertension, such that the blood pressure in their capillaries was elevated, then net filtration pressure would be

above normal.

Angiogenesis

allows for an increase in the perfusion of a local tissue.

In general, as an artery's diameter decreases, the artery walls show

an increase in the relative amount of smooth muscle and a decrease in the relative amount of elastic fibers

If someone were to have abnormally low levels of protein in their blood, then net filtration pressure would

be higher than normal.

Increased cardiac output ________ the blood pressure.

increases

The respiratory pump assists blood movement within the veins of the trunk, because as a person inspires,

intra-abdominal pressure increases and intrathoracic pressure decreases.

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

is called the blood pressure.

A portal system

is one in which blood flows through two capillary beds before being sent back to the heart.

Imagine someone who drank too much water before running a race. Their very watery blood would have

low viscosity and therefore have low resistance

Concerning the exchange between blood and interstitial fluid at systemic capillaries,

more fluid is filtered than reabsorbed.

Net filtration pressure (NFP) is equal to the

net hydrostatic pressure minus the net colloid osmotic pressure.

If someone were to decrease their food intake and increase aerobic exercise, they might lose adipose tissue and condition their muscles. These changes would also influence their blood vessels, as there would be

regression of blood vessels in adipose tissue and angiogenesis in skeletal muscle

Circulation to the spleen demonstrates a(n)

simple pathway, as one artery delivers blood and one vein drains the organ.

Tissue damage can trigger local release of histamine, which can

stimulate release of nitric oxide, a vasodilator.

At a capillary bed, a vasoconstrictor

stimulates precapillary sphincters and decreases local blood flow.

Atherosclerosis involves a

sustained increase in resistance that leads to increases in arterial pressure to maintain adequate blood flow.

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.