Ch 21-Regulation of MAP
As blood oxygen levels ______, the chemoreceptors increase their frequency of action potentials.
decrease
Release of renin occurs in response to a(n) ______ in blood pressure.
decrease (trying to increase)
As action potentials from the baroreceptors to the vasomotor center increase in frequency, the output of the vasomotor center to peripheral blood vessels ______.
decreases
Chemoreceptors ______ respond strongly to minor decreases in blood oxygen levels.
do not
he time-frame for regulation of blood pressure by the renin-angiotensin-aldosterone mechanism is ______.
for several hours
The chemoreceptor reflex response to increased CO2 and increased H+ levels in blood is to cause a(n) ______ in vasomotor tone
increase
Select the choices that describe the actions of the adrenal medullary mechanism.
is rapid-acting, responds in the short-term, responds within seconds
Heart rate, stroke volume, cardiac output, and peripheral resistance all influence ______.
mean arterial pressure
Indicate vascular changes that occur with exercise.
opening of capillary beds of skeletal muscles, vasodilation of skeletal muscle vessels
The conversion of angiotensinogen to angiotensin I is catalyzed by the enzyme ______.
renin
Neural and hormonal mechanisms are involved in the ______-term regulation of blood pressure.
short
List the actions of angiotensin II.
stimulate release of aldosterone, stimulate release of ADH, stimulate vasoconstriction
What stimulates the release of aldosterone?
Increased plasma K+ concentrations, Decreased plasma Na+ concentrations
Describe the duration of the response of the adrenal medullary mechanism of blood pressure control.
Seconds to hours
Large decreases in blood pressure, stressful conditions and increases in physical activity all can trigger the ______.
adrenal medullary mechanism
_______ is released in response to an increased plasma K+ concentration and/or a decreased plasma Na+ concentration. It is also released in response to angiotensin II.
aldosterone
Name the hormone which causes vasoconstriction and decreases the rate of urine production.
antidiuretic hormone (renin doesn't directly cause vasoconstriction)
name a baroreceptor reflex
aortic arch reflex, carotid sinus reflex