Tissue fluid

What is tissue fluid?

Is plasma that has leaked from capillaries.

How does it form?

There are gaps in between the endothelial cells of the capillaries. The small molecules in plasma are forced out through gaps by high Hydrostatic Pressure (due to blood pressure)

Compared to blood:
Composition:
(Identical except...)

• No red blood cells
• No platelets
• Fewer white blood cells
• No large plasma proteins

Other differences:

• Tissue fluid has lower hydrostatic pressure 
• Tissue fluid has higher water potential
• Tissue fluid is not contained in vessels

Compared to Lymphatic fluid:

Composition:

(Lymph has these differences...)

• More white blood cells
• More globular proteins (antibodies)
• Less glucose
• Fewer amino acids 
• More triglycerides (absorbed in ileum)

Other differences:

• Lymphatic fluid is contained in vessels