First generation after a cross is

Options

A. First filial generation
B. `F_(1)` generation
C. Second filial generation
D. Both A and B

Answer

To answer the question "What is the first generation after a cross?" we can break down the solution into a series of steps:

### Step-by-Step Solution:

1. **Understanding Generations in Genetics**:
- In genetics, when we perform a cross between two organisms, we refer to the original parents as the **P generation** (Parental generation).

2. **Identifying the First Generation**:
- The offspring produced from the P generation are referred to as the **F1 generation** (First filial generation). This is the first generation that results from the cross of the parental generation.

3. **Example of a Cross**:
- For instance, if we have a tall plant (TT) crossed with a short plant (tt), the offspring (F1 generation) will all be heterozygous (Tt), which means they will exhibit the dominant trait (tall).

4. **Further Generations**:
- If we then cross two F1 individuals (Tt x Tt), the resulting offspring will be referred to as the **F2 generation** (Second filial generation).

5. **Conclusion**:
- Therefore, the first generation after a cross is known as the **F1 generation**.

### Final Answer:
The first generation after a cross is called the **F1 generation**.

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