Red blood cells do what in the body?
Red blood cells (also referred to as erythrocytes)
are the most common type of blood cell and the vertebrate
organism's principal means of delivering oxygen (O2) to the body
tissues via the blood flow through the circulatory system. They
take up oxygen in the lungs or gills and release it while squeezing
through the body's capillaries.
These cells' cytoplasm is rich in hemoglobin, an iron-containing
biomolecule that can bind oxygen and is responsible for the blood's
In humans, mature red blood cells are flexible biconcave disks
that lack a cell nucleus and most organelles. 2.4 million new
erythrocytes are produced per second. The cells develop in the
bone marrow and circulate for about 100-120 days in the body before
their components are recycled by macrophages. Each circulation
takes about 20 seconds. Approximately a quarter of the cells in the
human body are red blood cells.
Red blood cells are also known as RBCs, red blood
corpuscles (an archaic term), haematids, erythroid
cells or erythrocytes (from Greek erythros for
"red" and kytos for "hollow", with cyte translated as
"cell" in modern usage). Packed red blood cells, which are made
from whole blood with the plasma removed, are used in transfusion