Video Transcript
Blood can be transfused between
individuals. The diagram provided shows which
blood group can receive blood from or donate blood to other groups. A student says, “People with blood
group A can receive blood from any other blood group.” Are they correct? Why? (A) No, as people with blood group
A cannot receive blood from those with blood group AB or group B. (B) No, as people with blood group
A cannot receive blood from those with group O or group AB. Or (C) yes, as the diagram
demonstrates that all other blood groups can donate blood to group A.
In order to answer this question,
let’s look at how these different blood groups are classified. Before we can do this, let’s first
clear the answer choices so we have more room to work with. There are four different blood
groups: A, B, AB, and O. Someone with blood group A has red
blood cells with type A antigen present on their surface. Someone with blood group B has red
blood cells with type B antigens present on their surface. You may have already guessed it,
but someone with blood group AB has red blood cells with type A and type B antigens
present on their surface. And finally, someone with blood
group O has red blood cells with neither type A nor type B antigens present on their
surface.
For each blood group, there are
also different antibodies that are present. In blood group A, there are anti-B
antibodies. These anti-B antibodies have a
specific shape that allows them to bind specifically to type B antigen. When this happens, an immune
response is initiated and the red blood cell is destroyed. So people with blood group A can’t
receive blood from blood group B because these anti-B antibodies would destroy those
red blood cells. And the same is true for blood
group AB because they also contain type B antigens. However, anti-B antibody can’t bind
to the person’s own type A antigen because the antigen isn’t compatible with this
antibody.
In someone with blood group B, they
have anti-A antibodies, which would react with any red blood cells that carry the
type A antigen. So someone with blood group B would
not be able to accept donations from those in blood group A or blood group AB
because they carry the type A antigen. A person with blood group AB
contains neither anti-A nor anti-B antibodies. If they did, then these antibodies
would attack their own red blood cells. Because they don’t have any anti-A
or anti-B antibodies, this person can receive blood from any blood group. Finally, a person with blood group
O has both anti-A and anti-B antibodies, so they would only be able to receive blood
from blood group O. And since they don’t have any
antibodies, they can donate to any of the blood groups.
All of this is indicated in the
provided diagram. O is able to donate blood to any
blood group, while AB is able to receive blood from any blood group. And groups A and B can only receive
blood from O or from their own blood group. So if we look at the statement in
this question that people with blood group A can receive blood from any other blood
group, this is incorrect because blood group A can’t receive blood from groups AB or
B.
