AP - exam 2 (cardiovascular, part 3)

blood pressure (BP)

what is the force per unit area exerted on wall of blood vessel by blood?

blood viscosity, total blood vessel length, blood vessel diameter

what factors regulate vascular resistance?

vasoconstriction

________ is defined as a decrease in the vessel lumen

taller

would a taller or shorter person have a higher total vascular length?

inversely

blood flow is ________ proportional to peripheral resistance (R)

directly

blood flow is ______ proportional to blood pressure gradient

aorta

where is blood pressure highest in the systemic circuit?

systolic pressure

what is the pressure exerted in aorta during ventricular contraction?

(hint: average = 120 mm Hg)

diastolic pressure

what is the lowest level of aortic pressure during ventricular diastole?

(hint: average = 80 mm Hg)

pulse pressure

what is the difference between systolic and diastolic pressure known as?

mean arterial pressure (MAP)

________ is the average pressure that propels blood to tissues

(hint: _____ = diastolic pressure + 1/3 pulse pressure)

high BP would rupture walls

why is low pressure desirable in capillaries?

muscular pump

what contacts skeletal muscle to "milk" blood toward heart, with valves presenting backflow?

respiratory pump

during breathing, what moves blood toward heart by squeezing abdominal veins as thoracic veins expand?

cardiac output, peripheral resistance, blood volume

what three main factors influence blood pressure?

baroreceptors

what are mechanoreceptor sensory neurons excited by stretching of blood vessel?

carotid sinuses, aortic arch, walls of large arteries of neck + thorax

where are baroreceptors located?

cardiovascular center

what contains clusters of sympathetic neurons in medulla and regulates cardiac output and blood vessel diameter?

vasomotor center

what maintains a moderate constriction, otherwise known as vasomotor tone in vessels (aka normal blood pressure)?

inhibiting, causing arteriole dilation and venodilation

if arterial pressure is high, how can baroreceptors decrease blood pressure via vasomotor and cardioaccelatory centers?

stimulating, causing decrease of cardiac output

if arterial pressure is high, how can baroreceptors decrease blood pressure via cardioinhibitory center?

long term control

baroreceptors are not effective for __________ of blood pressure

chemoreceptors

what are present in the aortic arch and large arteries in neck that detect increases in CO2 or drops in pH or O2?

stress

hypothalamus increases blood pressure during ______ and mediates redistribution of blood flow during exercise + body temperature changes

angiotensin II

what active hormone causes vasoconstriction by directly increasing blood pressure?

(hint: ACE inhibitors)

atrial natriuretic peptide (ANP)

what hormone decreases blood volume + pressure and is produced by the cardiac muscle cells in the atria?

eliminates more urine

when blood pressure/volume increases, kidneys __________, which decreases blood pressure

conserves water and eliminates less urine

when blood pressure/volume decreases, kidneys ___________, which increases blood pressure

renin

when blood pressure decreases, what hormone is released by the kidneys in the first step of the renin-angiotensin-aldosterone mechanism?

angiotensin I

angiotensinogen (enzyme produced by liver) is converted to ___________ (an inactive peptide hormone) by renin

angiotensin converting enzyme (ACE)

what converts angiotensin I to angiotensin II, which is the active hormone that increases blood pressure?

primary hypertension

what type of hypertension consists of 90% of related conditions, with risk factors heredity, diet, obesity, age, diabetes mellitus, stress and smoking?

secondary hypertension

what type of hypertension is less common and usually involves renal or endocrine disorders?

90/60 mm Hg

what is the BP reading to be diagnosed with hypotension?

orthostatic hypotension

what type of hypotension involves temporary low BP + dizziness when suddenly rising from reclined position?

chronic hypotension

what type of hypotension is due to poor nutrition and is a warning sign for Addison's disease or hypothyroidism?

acute hypotension

what type of hypotension is an important sign of circulatory shock?

hypovolemic shock

what type of circulatory shock results from large-scale blood loss?

vascular shock

what type of circulatory shock results from extreme vasodilation + decreased peripheral resistance?

(hint: septic shock, anaphylactic shock, neurogenic shock)

cardiogenic shock

what type of circulatory shock results from inefficient heart pumping that cannot sustain adequate circulation?