type A blood

biology

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Last updated

July 14, 2026

Quick Summary

Type A blood is one of the four main blood types in the ABO blood group system, discovered by Karl Landsteiner in 1901. This system classifies blood based on the presence or absence of A and B antigens on the surface of red blood cells. Individuals with type A blood have A antigens on their red blood cells and produce antibodies against B antigens. This is crucial for blood transfusions, as mixing incompatible blood types can lead to a dangerous reaction where antibodies attack the foreign red blood cells. Type O blood is the most common globally.213

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ABO blood group system
Persons may thus have type A, type B, type O, or type AB blood. The A, B, and O blood groups were first identified by Austrian immunologist Karl Landsteiner in 1901. See blood group.
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Persons may thus have type A, type B, type O, or type AB blood. The A, B, and O blood groups were first identified by Austrian immunologist Karl Landsteiner in 1901. See blood group.
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therapeutics
Blood and blood cells
…1900, when the blood types A, B, and O were identified and cross-matching of the donor’s blood against that of the recipient to prove compatibility became possible. When blood with the A antigen (type A or AB) is given to someone with anti-A antibodies (type B or O blood), lysis…
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…1900, when the blood types A, B, and O were identified and cross-matching of the donor’s blood against that of the recipient to prove compatibility became possible. When blood with the A antigen (type A or AB) is given to someone with anti-A antibodies (type B or O blood), lysis…
Read More