Blood type

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Temperature101

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Can someone tell me which section on TBR bio that talks about blood type? I cant find it anywhere on TBR...I thought it would be in the immunology section but it's not there.
 
Hey.

mr chievous is correct, there is not much that you have to know regarding blood types.

That being said, there are a few important features that you should know:

Firstly, A, B, and O specify ANTIGENS that appear on the surface on the red blood cells. If you naturally have these antigens, the T-lymphocytes that would seek them out have been destroyed.

So, if you have an AB blood type, you can receive type A blood. Why? Even though the new blood doesn't have a type B antigen, you're body only tests for the presence antigens, not their absence.

This is why AB is the universal acceptor.

O blood type means that it has NEITHER the A nor B. antigens.

edited: Please see below for MedPR's response.

I'm not sure if you need to know about the Rh factor.
 
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Hey.

mr chievous is correct, there is not much that you have to know regarding blood types.

That being said, there are a few important features that you should know:

Firstly, A, B, and O specify ANTIGENS that appear on the surface on the red blood cells. If you naturally have these antigens, the T-lymphocytes that would seek them out have been destroyed.

So, if you have an AB blood type, you can receive type A blood. Why? Even though the new blood doesn't have a type B antigen, you're body only tests for the presence antigens, not their absence.

This is why AB is the universal acceptor.

O blood type means that it has NEITHER the A nor B. antigens.

You could say that they have co-dominance. (You see both phenotypes.)
I'm not sure if you need to know about the R factor.


That's incorrect. ABO typing is an example of incomplete dominance, not codominance. In a type-O you don't see either phenotype. The genotype of phenotype type-O is ii. Also, be careful when you talk about AB being the "universal acceptor." You still have to consider the Rh factor. Further, even an AB+ recipient can have a transfusion reaction if they are transfused with whole blood. Packed blood, however, will likely be fine.
 
Even packed blood (that is, packed pure packed RBCs lacking plasma, coagulation factors, and platelets; usually Oneg) can be "incompatible" because RBCs have many many more surface antigens then just ABO groups and the Rh factor. The clinical significance of any postransfusion hemolysis is usually negligible though and not really usually worried about in real practice. I really don't think any of this will be on the mcat lol
 
That's incorrect. ABO typing is an example of incomplete dominance, not codominance. In a type-O you don't see either phenotype. The genotype of phenotype type-O is ii. Also, be careful when you talk about AB being the "universal acceptor." You still have to consider the Rh factor. Further, even an AB+ recipient can have a transfusion reaction if they are transfused with whole blood. Packed blood, however, will likely be fine.

I thought ABO typing was an example of codominance.... In AB blood type both genes are expressed not a blending of the phenotype or incomplete dominance.
 
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I thought ABO typing was an example of codominance.... In AB blood type both genes are expressed not a blending of the phenotype, which is incomplete dominance.

The way I like to remember the difference is with flower color.

Incomplete dominance = plant with pink flowers.
Codominance = red and white flowers on the same plant. If blood types were codominant, then in an AB genotype, you'd have 50% erythrocytes with type A ag, and the other 50% with type B ag.
 
The way I like to remember the difference is with flower color.

Incomplete dominance = plant with pink flowers.
Codominance = red and white flowers on the same plant. If blood types were codominant, then in an AB genotype, you'd have 50% erythrocytes with type A ag, and the other 50% with type B ag.

Ok...Congrats on your MD acceptance, which school.
 
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