tissue fluid Flashcards
(7 cards)
1
Q
what is tissue fluid?
A
- fluid containing water, glucose, amino acids, fatty acids, ions, and oxygen
- bathes the tissues
2
Q
how is tissue fluid formed?
A
- capillaries have small gaps in walls so liquid and small molecules can be forced out
- as blood enters, ions, and oxygen are forced out capillaries, small diameter results in high hydrostatic pressure
- so water, glucose, amino acids, fatty acids, ions, and oxygen are forced out (ultrafiltration)
3
Q
what molecules ARE forced out of the capillary?
A
- water molecules
- dissolved minerals and salts
- glucose
- small proteins and amino acids
- fatty acids
- oxygen
4
Q
what molecules REMAIN in the capillary?
A
- red blood cells
- platelets
- large proteins
5
Q
how is tissue fluid reabsorbed?
A
- large molecules (plasma proteins) remain in the capillaries
- this lowers water potential of liquid in capillaries
- water in tissue fluid moves back into capillaries via osmosis
within this water, there is dissolved waste molecules that cells are releasing
e.g. carbon dioxide + urea released from respiration
( this is how waste from cells get reabsorbed into blood to be removed from body)
6
Q
will all liquid be reabsorbed by osmosis?
A
no
7
Q
why isnt all the liquid reabsorbed by osmosis
A
- eventually an equilibrium is reached
- osmosis cannot take place because there is no longer a water potential gradient
- so rest of tissue fluid is absorbed into lymphatic system (this fluid is called lymph) + eventually drains into the bloodstream near the heart
