What is blood? What is blood made of?

In the life of any creature on our planet, water is of paramount importance. Being a liquid, it not only dissolves in itself almost all substances, but can also transport them throughout the body. Let’s consider a few examples of the importance of water in the body of animals and plants.

Blood composition
Blood is a connective tissue made up of plasma (intercellular fluid) and blood cells.

Plasma is 90% water. Various substances are dissolved in it:

0.9% – sodium chloride (therefore, the blood tastes salty);
0.12% – glucose (if the% is more, insulin transforms it into glycogen, which is stored in the liver);
the rest is various proteins, amino acids, other salts and carbohydrates, fats.

Blood cells differ in structure and function:

erythrocytes – red biconcave discs without nuclei, which transfer oxygen and carbon dioxide on their surface to the places of gas exchange (red color is associated with the presence of hemoglobin);
platelets are the smallest colorless cells that do not have a nucleus; provide blood clotting in case of injury;
leukocytes – protect the body from various infections; large cells that have no color, but which have a nucleus.

Thus, the blood carries substances throughout the body and provides immunity.