NEET2026BiologyChapterActual
A blood sample from a patient is analyzed and found to contain both anti-A and anti-B antibodies in the blood plasma. Which of the following correctly identifies the patient's blood group and the status of antigens on the surface of their red blood cells (RBCs)?
Options
- ABlood group AB; Both antigens A and B are present on RBCs
- BBlood group O; Both antigens A and B are absent on RBCs
- CBlood group O; Both antigens A and B are present on RBCs
- DBlood group AB; Both antigens A and B are absent on RBCs
Correct answer
B. Blood group O; Both antigens A and B are absent on RBCs
Step-by-step solution
The ABO blood grouping system is based on the presence or absence of two surface antigens, A and B, on the red blood cells (RBCs). The plasma of different individuals contains natural antibodies, anti-A and anti-B. Individuals with blood group O do not have any antigens (neither A nor B) on the surface of their RBCs. Because they lack these antigens, their immune system produces both anti-A and anti-B antibodies in the blood plasma. Therefore, a blood sample containing both anti-A and anti-B antibodies belongs to b