<Tr> <Th> MeSH </Th> <Td> D004912 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terms of microanatomy (edit on Wikidata) </Td> </Tr> <P> Red blood cells--also known as RBCs, red cells, 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 (O) to the body tissues--via blood flow through the circulatory system . RBCs take up oxygen in the lungs, or gills of fish, and release it into tissues while squeezing through the body's capillaries . </P> <P> The cytoplasm of erythrocytes is rich in hemoglobin, an iron - containing biomolecule that can bind oxygen and is responsible for the red color of the cells . The cell membrane is composed of proteins and lipids, and this structure provides properties essential for physiological cell function such as deformability and stability while traversing the circulatory system and specifically the capillary network . </P>

What are red blood cells and what do they do
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