what does blood do in the human body
Blood Blood is a body fluid in humans and other animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells.[1]
Red blood cell Red blood cells-- also known as RBCs, red cells,[1] red blood corpuscles, haematids, erythroid cells or erythrocytes (from Greek erythros for "red" and kytos for "hollow vessel", with -cyte translated as "cell" in modern usage), are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissuesâ€”via blood flow through the circulatory system.[2] RBCs take up oxygen in the lungs, or gills of fish, and release it into tissues while squeezing through the body's capillaries.