Lecture 23

Question 1

Causes on inc HR with onset of exercise

Answer 1

dec parasympathetic tone (vagus nerve)

inc sympathetic tone

Question 2

Effect of exercise on SV(2)

Answer 2

inc EDV: either need bigger vessel to come through or inc in the rate of blood flow(latter is more likely)
inc EF/dec ESV

Question 3

inc EDV (preload) is caused by

Answer 3

inc venous return to the heart

Question 4

inc EF due to contractility (3 things that inc contractility)

Answer 4

frank-starling
inc sympathetic tone
dec afterload

Question 5

Increased CO during exercise is due to (think about the formula)

Answer 5

inc HR
-inc sympathetic tone, dec parasympathetic tone
inc SV
-inc preload
-dec afterload-make the pipes bigger (easier to pump out)
-inc contractility

Question 6

Blood flow distribution during exercise(2)

Answer 6

reduction in blood flow to organs(intestines, kidneys

inc blood flow to muscles

Question 7

Blood flow distribution during exercise mechanisms(4)

Answer 7

inc sympathetic tone (peripheral vasoconstriction)
local vasodilatory products in working muscle
inc in vascular resistance in some vascular beds (splanchic)
dec vascular resistance in muscles