Blood Vessels pt. 2

Question 1

What factors affect tissue perfusion?

Answer 1

Cardiac output, Peripheral Resistance, Blood pressure

Question 2

What are the 3 mechanisms that help with cardio regulation and what do they do?

Answer 2

Autoregulation
- Causes immediate homeostatic adjustments
- If autoregulation fails, neural and endocrine are implemented

Neural Mechanism
- Changes in arterial pressure and blood gas levels

Endocrine Mechanism
- Releases hormones for short-term adjustments

Question 3

What do the cardioacceleratory and cardioinhibitory centers do?

Answer 3

cardioacceleratory center increases cardiac output through sympathetic innervation.

cardioinhibitory center decreases cardiac output through para-sympathetic innervation

Question 4

What 2 centers combine to form the cardiovascular center?

Answer 4

Cardiac center + vasomotor center = cardiovascular center

Question 5

What is the vasomotor center (neurons)?

Answer 5

Neurons for widespread vasoconstriction and neurons for small vasodilation in arterioles and brain

Question 6

What are the baroreceptor and chemoreceptor reflexes?

Answer 6

Baroreceptor reflex - responds to changes in blood pressure
Chemoreceptor reflex - monitors changes in chemical composition of arterial blood

Question 7

What hormones affect cardiovascular output?

Answer 7

antidiuretic hormone (ADH)
angiotensin II
erythropoietin (EPO)
natriuretic peptides (ANP and BNP)

Question 8

What happens to your cardiovascular system when you have light exercise?

Answer 8

Increase in sympathetic activity
Extensive vasodilation
Venous return increases
Cardiac output increases

Question 9

Whats happens to your cardiovascular system when you have heavy exercise?

Answer 9

Cardioacceleratory increase cardiac output to 20-25 liter per min
Vasomotor center restricts blood flow to unnecessary organs (ex. Digestive system)
Body temperature increases

Question 10

What are the short term responses to hemorrhaging?

Answer 10

increase in cardiac output + cause vasoconstriction
Constricting arterioles → higher blood pressure
Short-term hormones
*Restores blood losses of up to 20%

Question 11

What are the long term responses to hemorrhaging?

Answer 11

Can take several days
Decrease in capillary blood pressure
Aldosterone and ADH activated to reduce blood loss
Thirst increases
Erythropoietin targets bone marrow, creates more RBC’s

Question 12

What is a stroke and what causes it?

Answer 12

Stroke (cerebrovascular accident) - when an artery is ruptured or blocked and dependent neurons are damaged or die