Blood is a tissue that consists of a fluid called plasma. Plasma carries red blood cells, white blood cells and platelets.Blood plasma transports:
- carbon dioxide from the organs to the lungs
- soluble products of digestion from the small intestine to other organs
- urea from the liver to the kidneys
Urea is a waste product formed in your liver from the breakdown of proteins into amino acids. In the kidneys, urea is removed from your blood in the form of urine. Your urine contains urea and mineral ions.