The three different alleles of human ABO blood types will produce how many genotypes & phenotypes respectively-

Options

A. `4&6`
B. `6&4`
C. `6&6`
D. `4&4`

Answer

To solve the question regarding the number of genotypes and phenotypes produced by the three different alleles of human ABO blood types, we can break it down step by step.

### Step 1: Understand the Concept of Multiple Allelism
Multiple allelism refers to a situation where a single gene has more than two alleles. In the case of human ABO blood types, there are three alleles: A (IA), B (IB), and O (IO).

**Hint:** Remember that multiple allelism allows for more than two variations of a gene.

### Step 2: Identify the Alleles and Their Dominance
The alleles for ABO blood types are:
- IA (A blood type) - dominant
- IB (B blood type) - dominant
- IO (O blood type) - recessive

**Hint:** Dominance determines how alleles express themselves in the phenotype.

### Step 3: Determine Possible Genotypes
The possible combinations of these alleles can be represented as follows:
1. IA IA (homozygous A)
2. IA IO (heterozygous A)
3. IB IB (homozygous B)
4. IB IO (heterozygous B)
5. IA IB (AB blood type)
6. IO IO (homozygous O)

Thus, the total number of genotypes is 6.

**Hint:** List all combinations of alleles to find the genotypes.

### Step 4: Determine Possible Phenotypes
The phenotypes corresponding to the genotypes are:
1. A (from IA IA or IA IO)
2. B (from IB IB or IB IO)
3. AB (from IA IB)
4. O (from IO IO)

Thus, the total number of phenotypes is 4.

**Hint:** Count the distinct observable traits (phenotypes) produced by the genotypes.

### Step 5: Conclusion
In summary, the three different alleles of human ABO blood types will produce:
- **Genotypes:** 6
- **Phenotypes:** 4

**Final Answer:** 6 genotypes and 4 phenotypes.

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