What is common to the techniques (i) in vitro fertilisation, (ii) Cryopreservation and (iii) tissue culture?

Options

A. All are in situ conservation methods.
B. All are ex situ conservation methods.
C. All require ultra modern equipment and large space.
D. All are methods of conservation of extinct organisms.

Explanation

To answer the question about what is common to the techniques of in vitro fertilization (IVF), cryopreservation, and tissue culture, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding In Vitro Fertilization (IVF)**:
- IVF is a process where fertilization occurs outside the body, in a laboratory setting. It involves the fusion of male and female gametes (sperm and egg) to create an embryo, which is then implanted into the mother's uterus. This technique is primarily used for assisting infertile couples.

2. **Understanding Cryopreservation**:
- Cryopreservation is a method used to preserve living cells, such as gametes (sperm and eggs), seeds, and other biological materials, by cooling them to very low temperatures (around -196°C). This process keeps the cells viable for long periods, allowing for future use.

3. **Understanding Tissue Culture**:
- Tissue culture involves growing plant cells or tissues in a controlled, artificial environment, typically using a nutrient medium instead of soil. This technique is used for mass propagation of plants and can be applied for conservation purposes as well.

4. **Identifying Commonality**:
- All three techniques (IVF, cryopreservation, and tissue culture) involve manipulating living cells or organisms outside their natural environments. They are not conducted in situ (in the natural habitat) but rather ex situ (outside of their natural habitat), under controlled laboratory conditions.

5. **Conclusion**:
- The commonality among IVF, cryopreservation, and tissue culture is that they are all **ex situ conservation methods**. They involve the preservation and manipulation of living organisms or cells outside their natural environments, under human care.

### Final Answer:
The common aspect of in vitro fertilization, cryopreservation, and tissue culture is that they are all **ex situ conservation methods**.

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