Lecture 32/33

Question 1

Sympathetic Influences on Vasculature During Exercise

Answer 1

SNS is active but we need high muscle blood flow

Beta-2 adrenergic receptors help to reduce vasoconstriction

Metabolites (hypoxia) counteract sympathetic vasoconstriction

Question 2

how is flow Redistributed during Exercise in skeletal muscle

Answer 2

Large increase in metabolic activity of skeletal muscles (metabolic > SNS = vasodilation)

Question 3

how is flow Redistributed during Exercise in Kidneys, liver, digestive tract

Answer 3

increase SNS activity leads to vasocontriction

Question 4

how is flow Redistributed during Exercise in the brain

Answer 4

no influence of SNS on blood flow

Question 5

how is flow distributed to the capillaries when SNS activity is high( stressed while sitting)

Answer 5

low flow (because of vasoconstriction)

reduced gas/nutrient exchange

fluid reabsorption > filtration

Question 6

how is flow distributed to the capillaries when SNS activity is high(muscle is active)

Answer 6

high flow (vasodilation)

increased gas/nutrient exchange

fluid filtration> reabsorption

Question 7

what are Capillaries

Answer 7

smallest blood vessels in the body

responsible for connecting the arterioles (smaller arteries) to the venules (smaller veins)

made up of a single layer of endothelial cells

Primary site of gas, nutrient, waste, and water exchange

Question 8

the capillaries are Only big enough for one RBC to flow through at a time; makes transfer of nutrients easier because there is less fluid for it to travel through. True or false

Answer 8

true

Question 9

Arterioles see the biggest drop in pressure and velocity. why?

Answer 9

it is slower because this allows time for diffusion

Question 10

explain the Gas and Nutrient Exchange Across the Capillary Wall

Answer 10

Gas and nutrient exchange across the capillary wall occurs through a process known as diffusion

Substances must pass through the capillary wall, through the interstitial fluid, to the tissue cells (and metabolic waste products go in the reverse direction)

Glucose needs an active transporter to bring it to the tissue cell (carrier-mediated transport); insulin

Question 11

how does Glucose pass into the tissue cell

Answer 11

Glucose needs an active transporter to bring it to the tissue cell (carrier-mediated transport); insulin