The amount of blood in the human body is about 7 ~ 8% of the body weight, such as weight 60 kg, the amount of blood is about 4200 ~ 4800 ml.
Blood vessel rupture caused by various reasons can lead to bleeding. If the blood loss is small, not more than 10% of the total blood volume, it can be quickly recovered through the body’s self-regulation. If the blood loss is large, up to 20% of the total blood volume, there will be rapid pulse, decreased blood pressure and other symptoms; If 30 percent or more of the body’s blood is lost in a short period of time, it can be life-threatening.
Blood is made up of four components: plasma, red blood cells, white blood cells and platelets. Plasma, which makes up about 55% of blood, is a mixture of water, sugar, fat, protein, potassium and calcium salts. Blood cells make up the other 45% of blood.
Based on the amount of blood in a human body, it would take about 1.1 million mosquitoes to suck the blood out of a human being.