blood, tissue fluid and lymph Flashcards
(20 cards)
What does the blood consist of?
Blood plasma with suspended blood cells and dissolved substances
What do the capillaries supply the cells with?
Oxygen, glucose, amino acids
What do the capillaries remove from the cells?
Carbon dioxide, urea
What are the substances exchanged over?
The tissue fluid
Which vessel divides into lots of capillaries?
Arterioles
What is high at the arteriole end of the capillary?
Hydrostatic pressure (blood pressure)
Why is water forced out of the capillaries?
The blood pressure is greater than the osmotic pressure
Which molecules pass through the capillary wall?
Water, glucose, amino acids and ions
What remains in the capillaries?
Blood cells and plasma proteins
What forms the tissue fluids?
The filtered plasma
What causes the blood pressure to lower?
The loss of fluid and the frictional resistance
What do the plasma proteins do to the water potential of the blood?
They lower it
What does this cause?
The osmotic uptake of water into the capillaries
Is hydrostatic pressure high or low at the venal end of the vein?
Low
What does this mean?
Osmotic potential is greater than hydrostatic pressure, so some water is reabsorbed
Where else does some of this tissue fluid go?
The lymph capillaries
Why do they go here?
Reabsorption into the blood is too slow
What is tissue fluid entering lymph capillaries called?
Lymph
What do lymph capillaries join to?
Lymph vessels which eventually return this tissue fluid into the blood
What does tissue fluid contain?
More blood plasma than larger proteins
