red blood cell: Quick Facts

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Last updated

Oct. 18, 2026

News •

Hand-cranked device tells blood type and red cell levels in 1 minute • Oct. 17, 2026, 12:00 PM ET (Phys.org)

Facts

Also Known As	erythrocyte • red corpuscle

Did You Know?

Human blood is about 44% red blood cells.
The human body can make 119 million red blood cells per second.
A red blood cell is 0.000007 of a meter in size.

Photos and Videos

Red blood cells

Illustration of a capillary cross section showing red blood cells moving from an artery to a vein. Arrows indicate oxygen and nutrients leaving the blood to enter body cells, while carbon dioxide and wastes enter the blood from body cells.

iron-deficiency anemia

Plasmodium vivax

Fibrin in blood clotting

blood smear showing sickle cell anemia

sickle cell anemia

blood cells in sickle cell anemia compared with healthy red blood cells

Trypanosome with human red blood cells (highly magnified).

Illustration of a blood vessel with a cutaway view showing red blood cells, white blood cells, platelets, and plasma, each labeled to highlight the main components of blood.

Observe a red blood cell as it travels from the heart to the lungs and other body tissues

Close-up of a medical blood bag filled with red blood, showing attached tubes and connectors against a blurred background.

Watch red blood cells travel through arteries and capillaries to deliver oxygen

Function of red blood cells explained

Sickle cell anemia explained

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Topics

mean corpuscular volume erythrocyte sedimentation rate mean corpuscular hemoglobin concentration hemagglutination Why are there different blood types?hemolysis sickle cell anemia thalassemia Anemia polycythemia white blood cell platelet reticulocyte

Dig Deeper: More Articles That Discuss This Topic

blood: Red blood cells (erythrocytes)

Key People

default image

William Hewson

English physiologist

Marcello Malpighi

Marcello Malpighi

Italian scientist

Oil painting by Jan Verkolje showing Antonie van Leeuwenhoek seated at a table with a globe, papers, inkstand, and a compass in hand, wearing a brown robe and white shirt.

Antonie van Leeuwenhoek

Dutch scientist

Swammerdam, Jan

Jan Swammerdam

Dutch naturalist

blood. Close-up of a technician drawing human blood with syringe from blood bag at a blood bank. Blood donation, Healthcare and medicine, needle

Exploring the Human Body Quiz