If one parent belongs to ‘A’ blood group and the other to ‘O’ blood group children possible represent:

Options

A. A and B group
B. AB group
C. A and O group
D. All four groups

Answer

To determine the possible blood groups of children when one parent has blood group A and the other has blood group O, we can follow these steps:

### Step 1: Identify the Genotypes of the Parents
- The parent with blood group A can have two possible genotypes:
- Homozygous: \( I^A I^A \)
- Heterozygous: \( I^A I^O \)
- The parent with blood group O has a genotype of \( I^O I^O \).

### Step 2: Set Up a Punnett Square
- We will consider both scenarios for the A blood group parent:
1. **If the A parent is homozygous** (\( I^A I^A \)):
- Possible gametes from A parent: \( I^A \)
- Possible gametes from O parent: \( I^O \)
- Punnett Square:
```
| I^A | I^A |
|---------|---------|
| I^O | I^A I^O | I^A I^O |
| I^O | I^A I^O | I^A I^O |
```
- All offspring will have the genotype \( I^A I^O \) (blood group A).

2. **If the A parent is heterozygous** (\( I^A I^O \)):
- Possible gametes from A parent: \( I^A \) and \( I^O \)
- Possible gametes from O parent: \( I^O \)
- Punnett Square:
```
| I^A | I^O |
|---------|---------|
| I^O | I^A I^O | I^O I^O |
| I^O | I^A I^O | I^O I^O |
```
- Offspring can have genotypes:
- \( I^A I^O \) (blood group A)
- \( I^O I^O \) (blood group O)

### Step 3: Calculate the Ratios
- From the homozygous A parent, all children will be blood group A.
- From the heterozygous A parent, there are:
- 50% chance of blood group A (\( I^A I^O \))
- 50% chance of blood group O (\( I^O I^O \))

### Conclusion
- If one parent is homozygous A, all children will be blood group A.
- If one parent is heterozygous A, there is a 50% chance for blood group A and a 50% chance for blood group O.
- Therefore, the possible blood groups of the children can be either A or O, with the ratios depending on the genotype of the A parent.

### Final Answer
- The possible blood groups of the children are:
- 50% blood group A
- 50% blood group O