In pea plants, yellow seeds are dominant to green. If a heterozygous yellow seeds plant is crossed wit a green seeded plant, what ratio of yellow and green seeded plants would you expect in `F_(1)` generation :-

Options

A. `3:1`
B. `50:50`
C. `9:1`
D. `1:3`

Answer

To solve the problem of determining the ratio of yellow and green seeded plants in the F1 generation when a heterozygous yellow seed plant is crossed with a green seeded plant, we can follow these steps:

### Step 1: Identify the Genotypes
- The yellow seed color is dominant, represented by the allele 'Y'.
- The green seed color is recessive, represented by the allele 'y'.
- The heterozygous yellow seed plant will have the genotype 'Yy' (one dominant and one recessive allele).
- The green seeded plant will have the genotype 'yy' (two recessive alleles).

### Step 2: Set Up the Cross
- We are crossing the heterozygous yellow seed plant (Yy) with the green seeded plant (yy).
- The cross can be represented as:
- Yy (heterozygous yellow) x yy (homozygous green)

### Step 3: Determine the Possible Gametes
- The gametes produced by the heterozygous yellow seed plant (Yy) can be:
- Y (dominant allele)
- y (recessive allele)
- The gametes produced by the green seeded plant (yy) can only be:
- y (recessive allele)

### Step 4: Create a Punnett Square
- Set up a Punnett square to visualize the possible combinations of alleles from the parents:

```
y y
----------------
| Y | y |
|-------|-------|
| y | y |
```

### Step 5: Analyze the Offspring Genotypes
- The resulting genotypes from the Punnett square are:
- Yy (yellow seeded)
- yy (green seeded)

### Step 6: Count the Ratios
- From the Punnett square, we see:
- 2 offspring with the genotype Yy (yellow)
- 2 offspring with the genotype yy (green)
- Therefore, the ratio of yellow to green seeded plants is:
- 2 yellow : 2 green, which simplifies to 1:1.

### Conclusion
- The expected ratio of yellow and green seeded plants in the F1 generation is 1:1.