Chapter 21 Practice

What is the net filtration pressure at the arterial end of the capillary?

+10 mmHg

vaso vasorum

A network of small blood vessels that supply large blood vessels

During shock which event would be likely to occur as part of the body's compensatory mechanism?

ADH secretion -to conserve fluid via the kidneys

precapillary sphincters

Circular muscle arrangement. Regulate blood flow to tissues

thromboxane A2

During the platelet release reaction, the postagladins __________ activates platelets and acts as a vasoconstrictor.

elastic recoil

If you exert a force on a solid shape, it responds by exerting a force in the opposite direction. This force is called ___.

Which statement about the movement of fluid between capillaries and interstitial space is NOT correct?

Interstitial fluid hydrostatic pressure is usually greater than blood hydrostatic pressure

The failure of the cardiovascular system to deliver enough oxygen to meet the metabolic needs of the cell is termed

Shock

blood hydrostatic pressure

The most significant pressure accounting for filtration pressure is...

Which statement about precapillary sphincters is CORRECT?

They can close off the capillaries by contracting

radial artery

What are you feeling for in a patient's wrist to find out their heart rate?

If blood pressure were too low, the cardiovascular control centers would attempt to compensate by causing

a decrease in heart rate increased sympathetic stimulation

cerebral ischemia

an interruption of the blood supply to an area of the brain; a common cause of medial temporal lobe amnesia.

conduct blood away from the heart

arteries

small arteries that lead to capillary beds

arterioles

In which choice are the blood vessels correctly ranked in order of decreasing wall thickness?

artery, arteriole, met arteriole, capillary

These two pressures, if positive, would both oppose capillary filtration.

blood (capillary) osmotic pressure and tissue hydrostatic pressure Pressures that oppose capillary filtration would either pull fluid (blood osmotic pressure) or push fluid (tissue hydrostatic pressure) into the capillary.

Which of these pressures forces molecules out of capillaries?

blood hydrostatic pressure

site of exchange of substances between the blood and tissue fluid

capillaries

The major factors determining blood pressure are

cardiac output and peripheral resistance

Which of the following types of shock is characterized by impaired heart function

cardiogenic

of the following, where are the most important baroreceptors located?

carotid sinus and aortic arch

Carotid sinus massage may inadvertently lead to

carotid sinus syncope

In a capillary bed, *relaxation* of the precapillary sphincters

causes more blood flow through the capillaries

Friction between the blood and vessel walls

causes peripheral resistance

If the blood pressure is elevated, the cardiovascular center would compensate by

causing vasodilation

Which of the following causes syncope?

cerebral ischemia

The largest arteries are the

conducting (elastic) arteries The large, elastic arteries branch into smaller, more numerous vessels as they lead toward the tissues.

Symptoms of shock

decreased BP, increased HR, skin-cool, clammy

Which of the following would NOT cause edema?

decreased capillary length

pulse pressure

difference between systolic and diastolic pressure

Which of the following would decrease mean arterial BP?

dilation of arterioles increased blood volume

What adds pressure to the blood in the arteries following ventricular systole and helps to maintain blood pressure during ventricular diastole?

elastic recoil As the muscle and elastic fibers in the arteries rebound after being stretched by the bolus of blood entering them during ventricular systole, they increase the peripheral resistance of the vessel, maintaining pressure in the system

Which of the following is NOT a symptom of shock?

elevated blood pressure

carotid sinus syncope

fainting due to inappropriate stimulation of the carotid sinus baroreceptors

Some capillaries contain these small openings in the endothelial cell wall.

fenestrations

Filtration is __ at the arteriole end of a capillary than at the venule end?

greater

If a person's blood pressure is 110/70, then

his pulse pressure is 40 mmHg

Which of these would increase the movement of fluid OUT of the capillaries?

increase in blood (hydrostatic) pressure

edema caused by

increased capillary blood pressure, decreased plasma proteins increased capillary permeability

Venous return would be increased by

increased skeletal muscle activity

vasoconstriction

increases arterial blood pressure As the diameter of the vessel decreases, the peripheral resistance increases, which increases blood pressure.

sphygmomanometer

instrument to measure blood pressure

The maximum pressure developed in a systemic artery

is called *systolic pressure*

Blood flow to a tissue will increase if the

level of carbon dioxide in the tissue increases

When taking blood pressure by the auscultatory method, the stethoscope is used to

listen for turbulent blood flow in the artery

Control of blood pressure is coordinated by this part of the brain

medulla oblongata

Blood is moved through the vascular system by

pressure gradients created by the heart

return blood from the tissues to the atria

pulmonary veins

The pulse is often taken in this artery near the base of the thumb

radial

Which substance leads to the formation of angiotensin II?

renin

The failure of the cardiovascular system to deliver enough oxygen to meet the metabolic needs of the cell is termed

shock

Each tissue type that is found in the wall of blood vessels has one or more specific functions that are necessary for the vessel to work correctly. In which of these choices is the tissue correctly matched with its role?

smooth muscle - allows the vessel to change its diameter

Which of the following best describes the myogenic response of smooth muscle?

smooth muscle contracts in response to stretch and relaxes in response to less stretch

The device used to measure blood pressure is called a(n)

sphygmomanometer

The colloid osmotic pressure of the blood is caused by

the presence of proteins in the plasma The capillary walls are not permeable to the numerous, large plasma proteins. This creates an osmotic pressure gradient.

Which of the following is FALSE regarding varicose veins?

they occur in all blood vessels (they don't)

What kind of vessel provides a bypass for a capillary bed?

thoroughfare channel The throughfare channels provide direct routes for blood between arterioles and venules. By allowing blood to bypass the capillary bed, they allow the blood in the capillaries to move more slowly. This promotes efficient exchange with tissue fluids while maintaining the overall speed and volume of blood flow through the system.

Which of the following would NOT cause vasodilation? (????)

thromboxane A2

A continuous capillary has _____ but NOT _____.

tight junctions; fenestrations

Small blood vessels in the tunica externa (adventitia) of a blood vessel that supply blood to the outer parts of the vessel wall are called

vaso vasorum

serves as a blood reservoir

veins