Implantation takes place after____of fertilisation.

Options

A. 5 days
B. 6 days
C. 7 days
D. 8 days

Explanation

**Step-by-Step Solution:**

1. **Understanding Fertilization**: Fertilization occurs when a haploid sperm cell fuses with a haploid ovum (egg cell), resulting in the formation of a diploid zygote. This is the first step in the process of human reproduction.

2. **Formation of the Zygote**: After fertilization, the zygote (which has a ploidy of 2n) begins to undergo cell division and development. This process is known as cleavage.

3. **Development of the Blastocyst**: As the zygote continues to divide, it eventually forms a structure known as the blastocyst. This is a hollow ball of cells that will later implant into the uterine wall.

4. **Timing of Implantation**: Implantation is the process where the blastocyst embeds itself into the endometrial lining of the uterus. This typically occurs approximately 7 days after fertilization.

5. **Conclusion**: Based on the above information, we can conclude that implantation takes place after 7 days of fertilization. Therefore, the correct answer is option 3: 7 days.

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