Round seed trait ( R) is dominant over wrinkled ( r) seed trait in Pea. Heterozygous round seede plant (Rr) is crossed with wrinkled seeded plant (rr). What is the possible progeny ?

Options

A. 302round :102 wrinkled
B. 210 round: 95 wrinkled
C. 105 round : 99 wrinkled
D. 103 round :315 wrinkled

Answer

To solve the problem of determining the possible progeny from the cross between a heterozygous round-seeded plant (Rr) and a wrinkled-seeded plant (rr), we can follow these steps:

### Step 1: Identify the Genotypes
- The heterozygous round-seeded plant has the genotype Rr (where R is the dominant allele for round seeds and r is the recessive allele for wrinkled seeds).
- The wrinkled-seeded plant has the genotype rr.

### Step 2: Set Up the Punnett Square
- We will set up a Punnett square to visualize the possible combinations of alleles from the two parents.
- The alleles from the heterozygous round-seeded plant (Rr) will be placed on one side of the square, and the alleles from the wrinkled-seeded plant (rr) will be placed on the other side.

```
R r
----------------
r | Rr | rr |
----------------
r | Rr | rr |
----------------
```

### Step 3: Fill in the Punnett Square
- Fill in the squares with the combinations of alleles:
- The first square (top left) combines R from Rr and r from rr, resulting in Rr (round seeds).
- The second square (top right) combines r from Rr and r from rr, resulting in rr (wrinkled seeds).
- The third square (bottom left) combines R from Rr and r from rr, resulting in Rr (round seeds).
- The fourth square (bottom right) combines r from Rr and r from rr, resulting in rr (wrinkled seeds).

### Step 4: Analyze the Progeny
- From the Punnett square, we see the following results:
- 2 squares show Rr (round seeds)
- 2 squares show rr (wrinkled seeds)
- This gives us a ratio of:
- 2 round-seeded plants (Rr)
- 2 wrinkled-seeded plants (rr)

### Step 5: Conclusion
- The ratio of round to wrinkled seeds is 1:1.
- Therefore, the possible progeny from this cross will be 50% round-seeded plants and 50% wrinkled-seeded plants.

### Final Answer
The possible progeny from the cross between a heterozygous round-seeded plant (Rr) and a wrinkled-seeded plant (rr) is:
- 50% Round-seeded (Rr)
- 50% Wrinkled-seeded (rr)