blood

Blood comprises red cells, white cells, platelets, and plasma. Red cells carry oxygen and carbon dioxide. White cells are our defense system. Platelets prevent bleeding.

Plasma is the liquid component of blood. It contains water, salts, sugars, and various proteinsProteins are made by cells. These are hormones, anti-bodies, cholesterol taxis for example. such as lipoproteins that can be compared to taxis with cholesterol as a passenger, or to antibodies, the proteinsProteins are made by cells. These are hormones, anti-bodies, cholesterol taxis for example. that protect against infection.