Total blood volume in the human body

The human body temperature is about 37 degrees, and it remains constant. The main reason is the existence of blood. The blood flow keeps the body temperature constant. The total amount of blood is a relatively certain number, which can reflect whether the body is healthy. The blood contains plasma and blood cells, and each part has a specific value. So what is the total amount of blood in the human body?

The total amount of blood in the human body is the sum of plasma and blood cells, but except for red blood cells, the number of other blood cells is very small and often negligible. The amount of blood in each person's body is determined by their weight. The total blood volume of a normal person is approximately equivalent to 7%-8% of body weight. For example, a person weighing 50 kg has about 4000 ml of blood, of which only 70-80% of the blood actually participates in circulation, and the rest is stored in the "human blood bank" such as the liver and spleen. When the body loses a small amount of blood, the blood stored in the "human blood bank" will be released immediately and replenished at any time. In addition, for people of the same weight, thin people have slightly more blood than obese people, and men have slightly more blood than women.

Blood is a red, opaque, viscous fluid that flows in human blood vessels and heart. Blood is composed of plasma and blood cells. One liter of plasma contains 900-910 grams of water, 65-85 grams of protein and 20 grams of low molecular substances. Low molecular substances include a variety of electrolytes and organic compounds. Blood cells include three types of cells: red blood cells, white blood cells and platelets. The average lifespan of red blood cells is 120 days, that of white blood cells is 9-13 days, and that of platelets is 8-9 days. Generally speaking, 40 ml of blood cells age and die per person every day. At the same time, a corresponding number of cells are generated. The functions of blood include blood cell function and plasma function. It has four functions: transportation, regulation of human body temperature, defense, and regulation of human body osmotic pressure and acid-base balance.

The main components are plasma, blood cells, and genetic material (chromosomes and genes). Belongs to connective tissue, which is the organizational level in living systems. The blood contains various nutrients, such as inorganic salts, oxygen, cellular metabolites, hormones, enzymes and antibodies, which nourish tissues, regulate organ activities and defend against harmful substances. Blood stores information about human health, and many diseases require blood tests. Including genetic diseases.