Cardiovascular System pt 3

Question 1

Describe the anatomy of a capillary

Answer 1

Single endothelial layer with basement membrane, intracellular clefts, vesicular channels, and plasmalemmal vesicles

Question 2

What are the 3 types of capillaries??

Answer 2

Continuous, fenestrated, and sinusoidal

Question 3

Where are continuous capillaries found?

Answer 3

Adipose tissue
All three muscle type
CNS
Lungs

Question 4

Where are fenestrated capillaries found?

Answer 4

Endocrine and Exocrine glands
Gall bladder
Synovial membrane
Choroid plexus
Renal medulla

Question 5

Where are sinusoidal capillaries found?

Answer 5

Liver
Spleen
Bone marrow

Question 6

What is the pressure entering capillaries?

Answer 6

25-35mmHg

Question 7

What is the pressure leaving the capillaries?

Answer 7

10-20mmHg

Question 8

Flow in the capillaries is determined by what?

Answer 8

Pressure gradient

Question 9

The pressure gradient in capillaries is dependent on what?

Answer 9

Pre and post capillary resistance

Question 10

How do you increase flow in capillaries?

Answer 10

Increase pressure on the arterial side

Question 11

How do you decrease the flow in capillaries?

Answer 11

Increase pressure on the venous side

Question 12

What are the three mechanisms for capillary exchange?

Answer 12

1. Diffusion
2. Bulk flow and Starling forces
3. Pinocytosis

Question 13

What is diffusion dependent on?

Answer 13

1. Concentration gradient
2. Surface area for exchange
3. Diffusion coefficient
4. Diffusion distance

Question 14

What is convective O2 transport?

Answer 14

This is dependent on Q through the capillary beds and the delivery of RBC

Question 15

What is diffusive O2 transport?

Answer 15

This is dependent on Fick’s law of diffusion and mitochondrial found in tissue

Question 16

What is the old theory of capillary recruitment?

Answer 16

Muscle fibers are surrounded by 4 capillaries but only one has continuous flow. When you exercise the remaining ones are recruited. This increases convective and diffusive O2 transport

Question 17

What is the new theory of capillary recruitment?

Answer 17

75-85% of capillaries have continuous flow. During exercise you increase the number of RBC running through the capillaries in order to increase conductive O2 and increase surface area

Question 18

Longitudinal capillary recruitment is produced by what?

Answer 18

1. Increase capillary flux
2. increase capillary hematocrit
3. increase RBC wall interface
4. increase diffusive transport and exchange

Question 19

What is bulk flow and the Starling forces?

Answer 19

This is the movement of solutes through capillary pores and is dependent on hydrostatic and osmotic pressure

Question 20

What is pinocytosis?

Answer 20

Endothelial cells ingest substance and form vesicle. It is then transported to the interstitial space and released

Question 21

What is the function of the lymphatic system?

Answer 21

Prevent the accumulation of excessive interstitial fluid

Question 22

How does the lymphatic system prevent accumulation of fluid?

Answer 22

Removes fluid and plasma proteins and returns it to systemic circulation

Question 23

What are the 4 factors in the formation of edema?

Answer 23

1. Increase capillary pressure
2. increase capillary permeability
3. decrease concentration of plasma protein
4. Obstruction of capillaries