In IVF-ET technology, developing embryo is implanted in the fallopian tube at

Options

A. Zygote stage
B. 8-celled stage
C. blastocyst stage
D. 32-celled stage

Answer

**Step-by-Step Solution:**

1. **Understand IVF-ET Technology**: In Vitro Fertilization and Embryo Transfer (IVF-ET) is a reproductive technology used to help couples who have difficulty conceiving. The process involves collecting mature eggs from the ovaries and fertilizing them with sperm in a laboratory setting.

2. **Fertilization Process**: After the eggs are collected, they are fertilized by sperm outside the body. This fertilization leads to the formation of an embryo.

3. **Embryo Development Stages**: The embryo goes through several stages of development after fertilization. The key stages include:
- Zygotic stage: This is the very first stage immediately after the sperm fertilizes the egg.
- 8-cell stage: This is when the zygote has divided into eight cells.
- 32-cell stage: This is a further division of the embryo, resulting in 32 cells.
- Blastocyst stage: This stage occurs approximately five to six days after fertilization when the embryo has developed into a hollow ball of cells.

4. **Implantation Timing**: In IVF-ET, the embryo is typically implanted into the uterus at the blastocyst stage. This stage is crucial because it allows the embryo to have the necessary structure for implantation into the uterine lining.

5. **Conclusion**: Therefore, the correct answer to the question is that in IVF-ET technology, the developing embryo is implanted in the fallopian tube at the **blastocyst stage**.

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