Lecture #5 Hemodynamics: Capillary Exchange

Question 1

Oxygen and nutrients move out of the blood by crossing the capillary wall and entering the _____.

Answer 1

Interstitial Fluid (ISF)

Question 2

Does the Carbon Dioxide and metabolic waste products move in the same or opposite direction?

Answer 2

Opposite Direction

Question 3

The concentration, or ______, of capillaries in a given tissue is proportional to the tissue’s _______.

Answer 3

density, metabolic activity

Question 4

What is the capillary bed?

Answer 4

Is a network of capillaries where exchange materials with the tissue cells can take place

Question 5

Every tissue cell is within ______diameters from a capillary.

Answer 5

2-3 cell

Question 6

How do the capillary cells move?

Answer 6

Most substance move by diffusion, which is efficient only when diffusion distances are short.

Question 7

What are the routes for capillary exchange?

Answer 7

Intercellular clefts, endotheliail cell membranes, fenestrations.

Question 8

Water and most small substances, cross capillary wall by diffusion through these pores is called _______.

Answer 8

Intercellular clefts

Question 9

Some small molecules and gases can diffuse or be transported across the endothelial cell layer is called______.

Answer 9

Endothelial cell membranes

Question 10

Large molecules can pass easily through the fenestrations is called _____.

Answer 10

Fenestrations (little window)

Question 11

What are the two mechanisms used for fluid exchange?

Answer 11

Passive process and active process.

Question 12

What materials pass through the capillary walls?

Answer 12

Diffusion, bulk flow, and transcytosis.

Question 13

Movement of molecular or ions from a region of higher concentration to one of lower concentration until equilibrium is reached is called what?

Answer 13

Diffusion

Question 14

Diffusion: passive or active process?

Answer 14

Passive

Question 15

Refers to the movement of a fluid from region of higher pressure to one of lower pressure is called what?

Answer 15

Bulk Flow

Question 16

Bulk flow: passive or active process?

Answer 16

Passive

Question 17

Substances enter pinocyotic vesicles move to endothelial cells via endocytosis, and exit on opposite side via exocytosis is called what?

Answer 17

Transcytosis

Question 18

Transcytosis: passive or active process?

Answer 18

Active

Question 19

Fluid exchange between ISF and capillaries occurs primarily by _____.

Answer 19

Bulk flow

Question 20

What two forces favor movement of fluid OUT of capillaries and into the ISF?

Answer 20

Blood Hydrostatic Pressure (BHP)

Question 21

Pushes Fluid through capillary pores is called?

Answer 21

Blood Hydrostatic Pressure (BHP)

Question 22

‘Pulls’ fluid out via osmosis; this pressure is very small compared to BHP is called?

Answer 22

Interstitial fluid osmotic pressure (IFOP)

Question 23

What two forces favor movement of fluid out of ISF INTO the capillaries?

Answer 23

Blood Colliod osmotic pressure and Interstital fluid hydrostatic pressure

Question 24

Differences in protein concentration between plasma and ISF tends to pull water from the ISF and into the capillaries is called?

Answer 24

Blood colloid osmotic pressure (BCOP)

Question 25

Pressure exerted by interstitial fluid, but it is typically very small is called?

Answer 25

Interstitial fluid hydrostatic pressure (IFHP)

Question 26

What is Net Filtration Pressure?

Answer 26

Net movement of fluid is driven by the difference between the inward and outward pressure

Question 27

What is the equation for net filtration pressure?

Answer 27

NFP= (BHP + IFOP) - (BCOP + IFHP) Push (Filtration) - Pull (Reabsorption)

Question 28

The ____ and ____ are the principle determiner of fluid movement across the capillary wall.

Answer 28

BHP and BCOP

Question 29

Results in a constant flow of fluid that washes over the tissue cells at the arterial end of the capillary, carrying nutrients and oxygen with it is called what?

Answer 29

Filtration

Question 30

What results in a return of fluid to the capillary at the venous end, thereby depositing wastes in the venous system?

Answer 30

Reabsorption

Question 31

Where does the fluid go when it does not enter the capillaries?

Answer 31

Lymphatic vessels and return to circulation