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