? Which is the mode of reproduction in amoeba 1 binary fission only 2 binary fission and Multiple Fission3 binary fission and conjugation 4 Multiple Fission only (answer the question with proper explanation)?

Question

Answer

In favourable condition amoeba undergoes Binary Fission. But in unfavourable condition its nucleus multies it self without dividing completely (cell membrane). Again on exposure to favourable condition its cell membrane cuts so that the amoeba comes out i.e multiple fission.

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Option 2.Under conditions of food shortages, amoebae will reproduce via multiple fission

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Under unfavourable conditions amoeba forms a cyst on its body then it shows multiple fission

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Mode of Reproduction in Amoeba

Amoeba is a single-celled organism that belongs to the kingdom Protista. It reproduces asexually through a process called binary fission. However, under certain conditions, it can also reproduce through multiple fission and conjugation.

1. Binary Fission:
Binary fission is the most common mode of reproduction in amoeba. It is a simple form of asexual reproduction where a single cell divides into two identical daughter cells. The process of binary fission in amoeba involves the following steps:

- The nucleus of the amoeba undergoes mitosis, resulting in the formation of two identical nuclei.
- The cytoplasm of the amoeba elongates and divides into two halves.
- A new cell membrane forms between the two halves, separating them into two individual daughter cells.
- Each daughter cell then grows in size and develops into a fully functional adult amoeba.

The process of binary fission allows amoeba to rapidly reproduce and increase its population in favorable conditions.

2. Multiple Fission:
Under unfavorable conditions such as scarcity of food or extreme temperatures, amoeba can resort to multiple fission as a survival strategy. Multiple fission is a form of asexual reproduction in which a single cell divides into multiple daughter cells simultaneously. The process of multiple fission in amoeba involves the following steps:

- The nucleus of the amoeba undergoes repeated rounds of mitosis, resulting in the formation of multiple nuclei.
- The cytoplasm of the amoeba divides into several parts, each containing one nucleus.
- A new cell membrane forms around each nucleus, creating individual daughter cells.
- These daughter cells are called spores and are usually dormant until conditions become favorable again.
- When conditions improve, the spores undergo germination and develop into fully functional amoebas.

Multiple fission allows amoeba to produce a large number of spores that can survive harsh conditions until suitable conditions for growth and reproduction return.

3. Conjugation:
Conjugation is a sexual mode of reproduction observed in some species of amoeba. It involves the exchange of genetic material between two individuals, resulting in increased genetic diversity. The process of conjugation in amoeba involves the following steps:

- Two amoebas come into contact and form a temporary connection called a conjugation bridge.
- The genetic material (nucleus) of one amoeba moves into the other through the conjugation bridge.
- The exchanged genetic material undergoes recombination, leading to the formation of new genetic combinations.
- After conjugation, both amoebas separate and continue their individual growth and reproduction.

Conjugation in amoeba allows for genetic variation, which can be advantageous for survival and adaptation to changing environments.

Conclusion:
In conclusion, the mode of reproduction in amoeba primarily involves binary fission, where a single cell divides into two identical daughter cells. However, amoeba can also reproduce through multiple fission under unfavorable conditions and through conjugation for genetic diversity. These different modes of reproduction enable amoeba to adapt and survive in different environments.

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