In vitro fertilisation is a technique that involves tranfer of which one of the following into the Fallopian tube ?

Options

A. Embryo only, upto 8 cell stage
B. Either zygote or early embryo upto 8 cell stage
C. Embryo of 32 cell stage
D. Zygote only

Explanation

**Step-by-Step Solution:**

1. **Understanding In Vitro Fertilization (IVF)**: In vitro fertilization is a reproductive technology that involves fertilizing an egg with sperm outside the body, in a controlled environment (in vitro).

2. **Gamete Collection**: The first step in IVF is the collection of gametes. The female's eggs (ova) and the male's sperm are collected.

3. **Fertilization Process**: The collected eggs are then fertilized by the sperm in the laboratory. This results in the formation of a zygote.

4. **Development of the Zygote**: After fertilization, the zygote begins to divide and develop into an early embryo. This early embryo is typically referred to as a blastomere.

5. **Transfer to the Fallopian Tube**: In IVF, the zygote or the early embryo (up to the 8-cell stage) is then transferred into the Fallopian tube or the uterus of the female for further development.

6. **Identifying the Correct Option**: The question asks which entity is transferred into the Fallopian tube during IVF. The correct answer is "either zygote or early embryo up to 8 cell stage," as both can be transferred during the IVF process.

7. **Conclusion**: Therefore, the correct option is **"either zygote or early embryo up to 8 cell stage."**

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