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
