Tissue fluid

Question 1

Outline how tissue fluid is formed

Answer 1

• The arteriole end of the capillary has high blood pressure, creating a pressure gradient.
• Fluid (filtered plasma) flows down this gradient and moves out of the capillary, transporting substances.
• This loss of liquid and friction causes a decrease of pressure at the end of the capillary.
• Large plasma proteins remain in the capillary reduce the water potential, causing the osmotic uptake of water.
• The osmotic potential is greater than blood pressure at the venule end, causing the reabsorption of tissue fluid.
• Some goes to the lymph capillaries as the process is slow and empties into the subclavian veins and is returned to the blood.

Question 2

How is osmotic uptake caused in the capillary?

Answer 2

The large plasma proteins reduce the water potential of the blood plasma.

Question 3

What causes low blood pressure?

Answer 3

The loss of fluid and frictional resistance reduces blood pressure.