heart and tissue fluid exam qs

Question 1

Explain how an arteriole can reduce the blood flow into capillaries

Answer 1

Muscle contracts;
2. Constricts/narrows arteriole/lumen;

Question 2

Give the pathway a red blood cell takes when travelling in the human circulatory system
from a kidney to the lungs.

Answer 2

Renal vein;
2. Vena cava to right atrium;
3. Right ventricle to pulmonary artery;

Question 3

The water potential of the blood plasma is more negative at the venule end of the capillary
than at the arteriole end of the capillary. Explain why.

Answer 3

Water has left the capillary;
2. Proteins (in blood) too large to leave capillary;
3. Increasing concentration of blood proteins (and thus wp).

Question 4

Explain the role of the heart in the formation of tissue fluid.

Answer 4

contracts and forces water (and some dissolved substances) out (of
blood capillaries

Question 5

Describe and explain four ways in which the structure of a capillary adapts it for the
exchange of substances between blood and the surrounding tissue.

Answer 5

permeable capillary wall
one cell thick - reduces diffusion distance;
3. flattened (endothelial) cells, reduces diffusion distance;
4. fenestration’s, allows large molecules through;