Download Using Blood Typing to Identify Babies KEY Blood group A If you

Using Blood Typing to Identify Babies KEY
Blood group A
If you belong to blood group A, you have A antigens on the surface of your red blood cells and anti-B
antibodies in your blood.
If you belong to blood group B, you have B antigens on the surface of your red blood cells and anti-A
antibodies in your blood.
If you belong to blood group AB, you have both A and B antigens on the surface of your red blood cells
and no anti-A or anti-B antibodies in your blood.
If you belong to blood group O, you have neither A nor B antigens on the surface of your red blood
cells, but you have both anti-A and anti-B antibodies in your blood.
Blood Group
Antigens on red
blood cells
Antibodies in
plasma
Can receive blood
from
Can give blood to
A
A
anti-B
A and O
A and AB
B
B
anti-A
B and O
B and AB
AB
A and B
none
A, B, AB, and O
AB
O
none
anti-A and anti-B
O
A, B, AB, and O
Which blood type would be considered a universal donor (someone who can give blood to anyone)? O
Which blood type would be considered a universal receiver (someone who can receive blood from
anyone)? AB
In a heterozygous IA i person, which allele is dominant, IA or i? IA is dominant because that is the
phenotype that is displayed.
Which one of the genotypes shown results in a phenotype that provides clear evidence of codominance?
IA IB
Now, suppose that a mother has blood Type A and genotype IA i and the father has blood Type B and
genotype IB i . Draw a Punnett square to show the possible genotypes and blood types for their
children.
IA
i
IB
IB IA
IB i
i
IA i
ii
Is it possible for Michael and Danielle to have a child who is type O? no
How do you know this? Two recessive i alleles must be present to have a type O offspring. Michael does
not have any recessive i alleles, and Danielle only has one, at most.
Was a switch made at the hospital? no
How could fraternal twins be as different in appearance as Michelle and Michael, Jr., including one
having light skin and the other having dark skin? If a recessive gene is present in both parents,
offspring may show that phenotype.