animal transport. Flashcards
Describe the layers of tissue in arteries and veins.
- Lumen
- Endothelium
- Elastic fibres
- Smooth muscle
- Collagen fibres
Describe the layers of tissue in a capillary.
- Lumen
- Endothelium
Function of arteries?
Carry blood away from the heart at high pressure.
Function of veins?
Carry blood back to the heart at low pressure.
Function of capillaries?
Allow exchange of materials between blood and cells of tissues.
Function of elastic fibres?
Allows wall the stretch and recoil.
Function of smooth muscle in arteries?
Contract and constrict the to limit blood flow.
Function of collagen fibres in arteries?
Gives strength to withstand the pressure.
Description and function of the lumen in arteries?
Narrow. Maintain high pressure.
Describe the endothelium in arteries?
Folded and can unfold when the artery stretches.
Description and function of the lumen in veins?
Wider. Has valves to prevent backflow.
Describe the endothelium in capillaries?
One cell thick. Short diffusion distance.
What is lymph moved by?
- Hydrostatic pressure.
- Contraction of body muscles (aided by valves in the lymph vessels).
What are the blood components?
- Red blood cells (erythrocytes)
- White blood cells (lymphocytes)
- Platelets
- Plasma
Function of plasma?
Carries all substances except for oxygen.
Define tissue fluid.
Fluid that surrounds cells in tissues.
Define hydrostatic pressure.
Pressure exerted by a liquid.
Define oncotic pressure.
Pressure exerted by plasma proteins in capillaries.
Define pressure filtration.
Hydrostatic pressure - oncotic pressure.
Function of hydrostatic pressure?
Pushes tissue fluid and small molecules out of the capillary, leaving cells and large proteins behind = ultrafiltration.
Function of tissue fluid?
Allows exchange of substances between the blood and cells.
Substances found in tissue fluid that is delivered to cells?
- Glucose
- Amino acids
- Fatty acids
- Salts
- Oxygen
Substances found in tissue fluid that is removed from cells?
Carbon dioxide and other waste.
