Why blood ab is the universal acceptor?

Blood group AB is the universal recipient or acceptor because it lacks anti-A and anti-B antibodies in its plasma. As a result, AB positive or AB negative individuals can receive blood from any blood group without causing an immune reaction.

When a person receives a blood transfusion, the donor's red blood cells must be compatible with the recipient's plasma. If the donor's red blood cells have antigens that are not present on the recipient's red blood cells, the recipient's immune system will recognize the donor's red blood cells as foreign and attack them. This can lead to a serious condition called a hemolytic transfusion reaction.

Blood group AB plasma does not contain any anti-A or anti-B antibodies, so it will not attack red blood cells of any blood group. This makes AB plasma compatible with all blood groups, and AB individuals can therefore receive blood from any donor without risk of a hemolytic transfusion reaction.

Here is a table showing the compatibility of blood groups for transfusion:

| Recipient Blood Group | Compatible Donor Blood Groups |

|---|---|

| A+ | A+, A-, O+, O- |

| A- | A-, O- |

| B+ | B+, B-, O+, O- |

| B- | B-, O- |

| AB+ | AB+, AB-, A+, A-, B+, B-, O+, O- |

| AB- | AB-, A-, B-, O- |

| O+ | O+, O- |

| O- | O- |

As you can see from the table, AB+ individuals can receive blood from any donor blood group, while AB- individuals can only receive blood from AB- or O- donors.