blood coming out of urethra - SportsID
Blood is a specialized fluid that constantly flows throughout your body. It’s made of plasma, red blood cells, white blood cells and platelets. It has four main components: plasma, red blood cells, white blood cells, and platelets.
Understanding the Context
The blood that runs through the veins, arteries, and capillaries is known as whole blood—a mixture of about 55% plasma and 45% blood cells. About 7% to 8% of your total body weight is blood. Blood circulates throughout the body, transporting substances essential to life. Here, learn about the components of blood and how it supports human health.
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Key Insights
The body contains about 5 to 6 quarts (about 5 liters) of blood. Blood performs various essential functions as it circulates through the body: Once blood is pumped out of the heart, it takes 20 to 30 seconds to make a complete trip through the circulation and return to the heart.