Ch.15 pt.2 UCardiovascular Physiology II

To what variables is blood flow directly proportional? To what variables is it inversely proportional?

UP: pressure, radius

DOWN: length, viscosity

To what variables is resistance directly proportional? To what variables is it inversely proportional?

UP: vessel length, viscosity

DOWN: radius, pressure

What hormones affect blood flow? How?

Angiostenin II, ADH, NE (alpha receptors) → Vasoconstriction

NE (beta receptors), AcH → Vasodilation

How does the ANS affect blood flow?

SNS → constrict blood flow to increase pressure to move blood faster for muscles and brain

PSNS → dilates blood flow to easier for blood to enter GI tract, etc.

What effect does vasoconstriction have on blood pressure?

• increases pressure upstream (UP TO BRAIN)

• decreases pressure down stream (less for GI tract lol)

What factors influence blood pressure?

UP: HR*SV (CO), TPR

The type of shock resulting from microbial infection is termed __________ shock.

 

hypovolemic

 

cardiogenic

 

septic

 

neurogenic

Septic

( Hypovolemic → blood loss/dehydration

Cardiogenic → heart failure

Neurogenic → LOST SNS function/less vasoconstriction → vasodilation

Cardiogenic shock can result from __________.

 

myocardial infarction

 

increased cardiac output

 

increased sympathetic outflow to the heart

 

parasympathetic antagonists

myocardial infarction (aka CARDIAC FAILURE)

Increased blood flow resistance is caused by __________.

 

increased blood vessel length

 

decreased blood viscosity

 

vasodilation

 

increased blood pressure

increased blood vessel length (more collisions for atoms along the way to destination)

Which is NOT a symptom of preeclampsia?

 

Hypertension

 

Proteinuria

 

Edema

 

Increased vasodilation

increased vasodilation (Preeclampsia is a disorder characterized by high BP, proteins in the urea , and edema/swelling)

Inhibition of the baroreceptor reflex would prevent proper regulation of all but __________.

 

heart rate

 

stroke volume

 

respiratory rate

 

blood pressure

respiratory rate (hr w/ cardiac control center, stroke volume w/ vasomotor center and BP b/c baro = pressure)

A decrease in total peripheral resistance would cause blood flow to __________.

 

increase

 

decrease

 

remain unchanged

increase (pressure down = flow up)

Hypertension increases afterload, making it more difficult for the ventricles to eject blood.

 

True

 

False

True (afterload is the pressure the heart must overcome to eject blood)

There is no sounds from vessels during __________ flow.

 

turbulent

 

Korotkoff

 

laminar

 

restricted

laminar (last sound of Korotkoff that records diastolic pressure

Which blood vessels have the lowest pressure?

 

Veins

 

Arterioles

 

Venules

 

Capillaries

veins (that’s why they need valves!)

To which factor is blood flow inversely proportional?

 

blood pressure

 

blood vessel radius

 

total blood vessel length

total blood vessel length (length UP = resistance UP = flow DOWN)

Arterial blood pressure is influenced by __________.

 

vasoconstriction in the peripheral arterioles

 

increased heart rate

 

increased stroke volume

 

All of the choices are correct.

All of the choices are correct. (

Hypertension may cause __________.

 

increased afterload

 

hypertrophy of the ventricles and valve defects

 

broken capillaries in tissues and organs

 

All of the choices are correct.

All of the choices are correct.

Endothelin causes __________.

 

vasoconstriction

 

vasodilation

 

no effect

vasoconstriction (on endothelium)

In response to increased internal temperature, blood flow to the skin will __________.

 

increase

 

decrease

 

remain unchanged

increase

Nitric oxide (NO) causes __________.

 

vasoconstriction

 

vasodilation

 

no effect

vasodilation (paracrine regulation)

A failure of blood pressure to increase upon standing is known as __________.

 

postural hypotension

 

postural bradycardia

 

postural tachycardia

 

postural atherosclerosis

postural hypotension (hypo = less, tension - pressure)

[ bradycardia → slow heart, tachycardia → fast heart, atherosclerosis → plaque build up in artery walls)

Increased baroreceptor response will lead to which of the following homeostatic responses?

 

Decreased total peripheral resistance

 

Increased cardiac rate

 

Increased ADH and aldosterone release

 

Decreased acetylcholine release

 

Increased epinephrine release

decreased total peripheral resistance (the brain wants to vasodilate, thus decreasing the resistance to lower BP)

The last Korotkoff sound occurs when the blood pressure is equal to __________ pressure.

 

atmospheric

 

systolic

 

diastolic

 

pulmonary

diastolic (aka laminar sound b/c goes quiet)

Hypertension can be treated by all of the following EXCEPT __________.

 

ACE inhibitors

 

calcium channel blockers

 

diuretics

 

sympathetic agonists

sympathetic agonists (would speed up your heart, like Epinephrine )

To which factor is blood flow directly proportional?

 

total blood vessel length

 

blood viscosity

 

blood pressure

blood pressure

In the baroreceptor reflex, when blood pressure is high

 

sympathetic stimulation of the heart increases

 

cardiac output then decreases to compensate

 

baroreceptors stop stimulating sensory neurons

 

vasoconstriction occurs to compensate

cardio output then decreases to compensate (