M4 practice assignment (connect quiz practice)
In which of these blood vessels will the blood encounter the highest resistance? An arteriole with a diameter of 0.25 millimeters An elastic artery with a diameter of 12 millimeters A muscular artery with a diameter of 8 millimeters A muscular artery with a diameter of 3 millimeters
An arteriole with a diameter of 0.25 millimeters
true or false: Heart rate and stroke volume decrease with a decrease in parasympathetic stimulation.
false
true or false: Increased sympathetic stimulation causes vasodilation, bringing elevated blood pressure back to normal.
false
type of capillary to its location: Organs that engage in rapid absorption or filtration of small molecules (e.g. kidneys)
fenestrated
When the sphincters are open, blood will _________ the capillary bed.
fill
This shift in fluid balance at the arterial end is due to a change in _____________ pressure.
hydrostatic
Caffeine is a positive chronotropic agent. What effect on cardiac output can we expect in an individual who just drank a large cup of caffeinated coffee?
increase in cardiac output
When taking blood pressure using a sphygmomanometer, which of the following is true of the diastolic BP?
it is recorded after the last pulse sound is heard
When one-third of pulse pressure is added to the diastolic pressure, a good estimate of _______________________ is obtained.
mean arterial pressure
Subtracting the diastolic blood pressure from the systolic blood pressure results in _________________, which is directly proportional to the overall strength of one's pulse.
pulse pressure
Constriction of these sphincters _____________ the blood flow through their respective capillaries.
reduces
type of capillary to its location: Areas where large proteins and cells need to enter or leave the bloodstream (e.g. liver and bone marrow)
sinusoids
Capillary beds have precapillary __________ at the junction of capillaries and the metarteriole.
sphincters
Digoxin is a positive inotropic agent that can be administered intravenously. What effect can be predicted in a patient who is treated with digoxin?
stroke volume will increase
During exercise, the amount of blood that returns to the heart increases dramatically. What change (if any) can be predicted about stroke volume?
stroke volume will increase
The highest pressure exerted on the arterial walls during the heart cycle is referred to as_______________________
systolic blood pressure
type of capillary to its location: Most tissues (e.g. skeletal muscle)
continuous
The ____________________ is measured when the heart is relaxing and represents the lowest pressure exerted in the walls of the arteries during the heart cycle.
diastolic blood pressure
When this occurs, blood is ____________ to tissue or organs elsewhere.
diverted
Estimate the MAP, if systolic blood pressure is 131 mmHg and diastolic blood pressure is 62mmHg.
85
Approximately what percent of fluid that exits the capillaries at the arterial end reenters the capillaries at the venous end?
90%
As blood vessel length increases, what happens to peripheral resistance and blood pressure?
Both peripheral resistance and blood pressure increase
Edema may be caused by?
Increased capillary filtration, Reduced capillary reabsorption, Obstructed lymphatic drainage
Nitric oxide is released by exercising muscle cells and causes vasodilation in nearby blood vessels. What effect (if any) will nitric oxide have on blood flow?
Nitric oxide causes an increase in local blood flow
Why does our blood pressure generally go up as we age?
Our arteries get "hard" and absorb less systolic force
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.
expand and recoil
arteries
Only have tunica interna.
capillaries
Typically, fluid filters ________the arterial end of a capillary.
out
Which substances leave the blood by diffusing directly through the plasma membrane of endothelial cells?
oxygen, steroid hormones, carbon dioxide
As training progresses and blood viscosity increases, what will happen to peripheral resistance in the athlete?
peripheral resistance will increase
Blood usually passes through one network of capillaries from the time it leaves the heart until the time it returns, but there are exceptions, notably the __________.
portal systems and anastomoses
Has vasa vasorum.
tunica externa
Provides a smooth surface to decrease resistance to blood flow
tunica interna
Has adrenergic, angiotensin II and pain receptors
tunica media
The only tunic that plays an active role in hemodynamics.
tunica media
The action potential from the brain to the heart travels along which nerve(s)?
vagus nerve
Have lower blood pressure.
veins
collapse when empty.
veins
Fluid will then osmotically reenter at the ___________ end.
venous
This fluid delivers materials to the cells and removes its ___________
waste