GRADE 11/12 LIFE SCIENCES: BLOOD GROUPS
1. BLOOD GROUPS (GRADE 11/12)
A blood group or blood type is based on the presence or absence of TWO proteins (A, B) on the surface of red blood cells.
Because two proteins are involved, there are four possible combinations or blood types (ABO groups):



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Type A - Only the A protein is present.
Type B - Only the B protein is present.
Type AB - Both proteins are present.
Type O - Neither protein is present (about 40 percent of the population).
In addition to the A and B proteins, there is THIRD protein involved called the Rh factor. The Rh factor is either present (+) or
absent (-). Therefore, blood types are described as the type and Rh factor (such as O+, A+, AB-).
2. HOW IS BLOOD DONATED? (GRADE 11/12)
Certain blood groups can safely donate to others or safely receive from others.
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Type O- is called the universal donor because it can be given to anybody; it has no protein to cause clumps.
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Type AB+ is the universal receiver because the recipient has all of the proteins and so will not form clumps.
Look at the chart below which shows which blood groups are compatible (ie can safely donate to others)
eg blood group O- can donate to A but NOT receive from A
Info from: The Australian Red Cross
Looking at the table above, write an INTERPRETATION OF THE TABLE in the space below:
Look at the following – universal donor, universal recipient, who can only donate to the same group, blood groups with + or – who
can they safely donate to?
Find out your own blood type if possible and the blood types of your parents and sisters/brothers and list these in the space below:
YOUR BLOOD GROUP
MOM’S
DAD’S
BROTHER’S
SISTER’S
3. BLOOD GROUP DISTRIBUTION IN SOUTH AFRICA (GRADE 11/12)
The general distribution of blood groupings in South Africa is illustrated in the table below.
Group
+
—
Total
O
38%
7%
45%
A
34%
6%
40%
B
9%
2%
11%
AB
3%
1%
4%
Total
84%
16%
100%
Convert this information into a bar graph
4. HOW ARE BLOOD GROUPS INHERITED? (GRADE 12)
There are three forms of the gene alleles) that control the ABO blood group, which are designated as iA, i B, and i. You have two
alleles (one from your mother and one from your father), which are referred to as your genotype. The inheritance of the alleles is
co-dominant, meaning that if the allele is present, it gets expressed. The following genotypes will yield these blood types:



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iAiA or iAi - Both genotypes produce the A protein (type A).
iBiB or iBi - Both genotypes produce the B protein (type B).
iAiB - This genotype produces the A and B protein (type AB).
ii - This genotype produces no protein (type O).
Phenotype
Genotype
Allelic genotype
A
AA or AO
IAIA or IAi
B
BB or BO
IBIB or IBi
AB
AB
IAIB
O
OO
ii
5. BLOOD TYPE CAN BE USED TO DETERMINE PATERNITY IN MANY CASES. (GRADE 12)
Our ABO blood type charts below can be used to predict the possibilities of paternity.
The charts below can assist you to determine either:
1.
2.
The ABO blood type of the child when the blood type of the father and the mother are known (top chart), or
The ABO blood type of the father if the blood type of the child and the mother are known (bottom chart).
ABO Blood Type Calculator
Info from:
http://www.canadiancrc.com/Paternity_determination_blood_type.aspx
http://health.howstuffworks.com/question593.htm
http://www.donateblood.com.au/page.aspx?IDDataTreeMenu=42&parent=30
http://www.blood.org.za/groups.html