Which one / ones is / are correct about the gametes produced by TtRr? It is not the case of linkage
A. 4 types of gametes will be formed.
B. The percentage of each gamete is 25.
C. Each gamete is diploid
D. Out of 4 gametes 2 gametes have all dominant genes.

Options

A. A,C,D
B. A,B,C,D
C. B,C,D
D. A,B

Answer

To solve the question regarding the gametes produced by the genotype TtRr, we will analyze each option step by step.

### Step 1: Determine the types of gametes produced by TtRr
The genotype TtRr consists of two gene pairs:
- Tt (where T is dominant and t is recessive)
- Rr (where R is dominant and r is recessive)

According to the principle of independent assortment, the alleles of different genes segregate independently during gamete formation.

### Step 2: List the possible combinations of alleles
From Tt, we can have:
- T (dominant)
- t (recessive)

From Rr, we can have:
- R (dominant)
- r (recessive)

Now, we can combine these alleles to form gametes:
1. TR (T from Tt and R from Rr)
2. Tr (T from Tt and r from Rr)
3. tR (t from Tt and R from Rr)
4. tr (t from Tt and r from Rr)

Thus, the four types of gametes produced are:
- TR
- Tr
- tR
- tr

### Step 3: Analyze the options
A. **4 types of gametes will be formed.**
- This statement is **correct** as we have identified 4 distinct gametes.

B. **The percentage of each gamete is 25.**
- This statement is also **correct**. Since there are 4 gametes, each type will have a probability of 1/4 or 25%.

C. **Each gamete is diploid.**
- This statement is **incorrect**. Gametes are haploid, meaning they contain only one set of chromosomes (one allele for each gene).

D. **Out of 4 gametes, 2 gametes have all dominant genes.**
- This statement is **incorrect**. The gametes TR and tR have one dominant allele each, but Tr and tr do not have all dominant genes. Only one gamete (TR) has both dominant alleles.

### Conclusion
The correct options are A and B.