Tissue Fluid Flashcards
What is tissue fluid?
The fluid that bathes all of the cells and is mainly water with dissolved molecules
What generates the hydrostatic pressure of blood?
Ventricle contraction
What generates osmotic pressure?
Water potential of tissue fluid is higher than the water potential of blood
How is tissue fluid formed at the arterial end of the capillary?
- hydrostatic pressure out is greater than osmotic pressure in
- therefore fluid is forced out of the capillary
How is water returned to blood at the venous end of the capillary?
- osmotic pressure in is greater than hydrostatic pressure out
- so water is reabsorbed by osmosis
What is lymph?
Similar to tissue fluid however, has more protein and white blood cells
What happens to excess tissue fluid?
- Excess tissue fluid enters lymph capillaries where it is now known as lymph
- Lymph capillaries join to from lymph vessels and empty into the subclavian veins, returning tissue fluid to the blood.
How does lymph flow through lymph vessels?
- Pressure is created by a build up of tissue fluid and muscle contractions squeezing the vessels
- Vessels also contain valves which prevent back flow
What is the role of lymph nodes?
Monitor substances to detect disease
How does high blood pressure lead to a build up of tissue fluid causing swollen tissues?
- more fluid is forced out at the arterial end of the capillary due to a higher hydrostatic pressure
- so less can drain back at the venous end
How can a low protein diet lead to a build up of tissue fluid causing swollen tissues?
- lower plasma proteins
- so blood has a higher water potential than normal
- the water potential gradient is lower than normal at the venous end
- so less water moves back in by osmosis
Explain how parasites living in lymph vessels leads to a build up of tissue fluid causing swollen tissues.
- excess tissue fluid cannot drain into lymph vessels
