Tissue Fluid

Question 1

Tissue fluid formation

Answer 1

1. At the atrioventricular end of the capillary there is a high hydrostatic pressure on the blood die to contractions of the left ventricle.
   The walls of the capillaries are permeable so small (soluble) molecules including water, glucose and oxygen are forced out -> sometimes called ultrafiltraion
2. The water and other substances form tissue fluid which bathes the cells and is an exchange medium

Question 2

Tissue fluid reabsorption

Answer 2

3. The hydrostatic pressure drops towards towards the venule end of the capillary due to water loss and friction between the blood and the capillary walls.
   Also larger soluble proteins become more concentrated with the loss of water -> decreasing the water potential pressure of the blood.
   Because the tissue fluid is mainly water, it has a Hugh water potential pressure - higher than the pressure in the blood.
   Water moves into the blood from tissue fluid, by osmosis, down its water potential potential gradient.
4. Any excess tissue fluid drains into lymphatic system.