How fluid leaves the capillaries from the arteriol
The hydrostatic pressure is higher than the osmotic pressure/solute potential difference.
This cancels the osmotic effect.
Fluid flows out of the capillaries.
How fluid enters the capillaries at the venous end
The hydrostatic pressure is lower than the solute potential difference.
Fluid moves into the capillaries.
However, not all fluid is reabsorbed.
How tissue fluid re-enters the blood
Tissue diffuses by osmosis into the lymph vessel due to the water potential gradient.
Once the tissue fluid enters a lymph vessel it is known as 'lymph'.
Lymph is returned to the blood via the subclavian vein.
Hydrostatic pressure is caused by the ventricles contracting.
Factors affecting hydrostatic pressure
- Further distance from heart
- Fluid decreases
- Friction caused by blood cells on capillary walls