Session 1

Question 1

Describe the course of blood flow

Answer 1

Heart - large elastic arteries - medium muscular arteries - arterioles - metarterioles - capillaries - post capillary venules - venules - medium veins - large veins - heart

Question 2

Describe the structure of the heart

Answer 2

Right and left ventricles on bottom
Right and left atria on top
Superior vena cava on top
Inferior vena cava posterior distal 
Pulmonary artery left 
Aorta on top 
Pulmonary veins poking out of sides

Question 3

Why do we need a cvs?

Answer 3

Diffusion cannot occur over large distances
To supply body with needs
O2 and nutrients
Waste products carried away

Question 4

Where does diffusion occur?

Answer 4

Capillaries

Question 5

How much of exchange is done via diffusion?

Answer 5

98%

Question 6

What is diffusion affected by?

Answer 6

Concentration gradient
Area
Diffusion distance

Question 7

How do molecules diffuse?

Answer 7

Pores

Or lipid soluble molecules diffuse through capillary walls

Question 8

Brains metabolic needs

Answer 8

Constant
0.5ml/min/g
Intolerant of flow interruption

750 ml/min to brain at all times

Question 9

Heart metabolic needs

Answer 9

1.2 ml/min
Constant blood supply
0.9ml/min/g but if heart has to work faster it can increase four fold
Intolerant of inadequate flow

Question 10

Kidney metabolic needs

Answer 10

High constant blood flow

Most not nutritive

Question 11

Gut and liver metabolic needs

Answer 11

Hepatic portal system
1ml/min/g
Digestion of meal increases flow

Question 12

Skeletal metabolic needs

Answer 12

Vary
0.3ml/min/g - 6ml/min/g
Can survive anaerobic metabolism

Question 13

Skin metabolic needs

Answer 13

0.01ml/min/g - 1.5-2ml/min/g in thermoregulation

Question 14

Why does blood flow change in some organs but remain constant in others?

Answer 14

Depends upon conc gradient driving exchange, flow of blood in capillaries, concentration of substances in blood entering tissue, exercise, gradient between capillaries and nearby cells