Human embryo will be called as a 'foetus' after:

Options

A. two months
B. six months
C. four months
D. seven months

Answer

To determine when a human embryo is called a 'fetus', we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Terms**:
- An embryo is an early stage of development that occurs after fertilization and before the fetus stage.
- A fetus is a more developed stage that comes after the embryonic stage.

2. **Identifying the Stages of Development**:
- The development starts with fertilization, leading to the formation of a zygote.
- The zygote undergoes several divisions to form a morula, then a blastula, and finally a gastrula.
- The gastrula stage leads to the formation of the three germ layers which eventually develop into the embryo.

3. **Duration of the Embryonic Stage**:
- The embryonic stage lasts until the end of the 10th week of pregnancy. This means that the embryo is present during this time.

4. **Transition to Fetus**:
- At the beginning of the 11th week of pregnancy, the embryo transitions into the fetal stage.
- This transition marks the end of the embryonic development phase and the beginning of the fetal phase.

5. **Converting Weeks to Months**:
- Since the question asks for the duration in months, we note that the transition occurs after 10 weeks, which is approximately 2.5 months.
- Therefore, by the end of the 2nd month (8 weeks), the embryo is still considered an embryo, and it becomes a fetus at the start of the 3rd month (around 10-11 weeks).

6. **Conclusion**:
- The correct answer to the question is that a human embryo will be called a 'fetus' after **2 months** of gestation.

### Final Answer:
The human embryo will be called a 'fetus' after **2 months**.

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