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

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding In Vitro Fertilization (IVF):**
- IVF is a reproductive technology that allows fertilization to occur outside the body, specifically in a laboratory setting. The term "in vitro" means "in glass," indicating that the fertilization process occurs in a controlled environment, such as a test tube.

2. **The Process of IVF:**
- In IVF, the eggs (ova) are collected from the ovaries and are fertilized by sperm in the laboratory. This results in the formation of a zygote.

3. **Development of the Zygote:**
- After fertilization, the zygote begins to divide and develop. It can reach different stages of development, such as the 2-cell stage, 4-cell stage, and up to the 8-cell stage.

4. **Transfer of the Zygote or Embryo:**
- The question specifically asks about the transfer into the fallopian tube. If the zygote is still at the single-cell stage or has divided up to 8 cells, it can be transferred to the fallopian tube. This procedure is known as ZIFT (Zygote Intra-Fallopian Transfer).
- If the embryo has developed beyond 8 cells, it is typically transferred to the uterus, which is referred to as IUT (Intra-Uterine Transfer).

5. **Choosing the Correct Option:**
- The options given are:
- A) Zygote only
- B) Embryo only up to 8 cell stage
- C) Either zygote or early embryo up to 8 cell stage
- D) Embryo of 32 cell stage
- Since the transfer can involve either the zygote or an early embryo (up to 8 cells), the correct answer is **C) either zygote or early embryo up to 8 cell stage**.

**Final Answer:**
C) Either zygote or early embryo up to 8 cell stage.

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