iii.2. What are the various Asexual Reproduction techniques used by microorganisms?

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iii.2. What are the various Asexual Reproduction techniques used by microorganisms?

Asexual reproduction can happen in various ways, which are explained below:

Diverse patterns of Microorganism Reproduction through Fission	Fission is a form of asexual reproduction where a single cell divides to produce two or more separate daughter cells. Patterns of Fission in Unicellular Organisms: For unicellular organisms, fission results in the creation of new individuals. Different patterns of fission have been observed among various organisms: Binary Fission: It is common in many bacteria and protozoa. The organism splits into two roughly equal halves. In organisms like the Amoeba, the split can occur in any plane. In more organized unicellular organisms, such as Leishmania (which causes kala-azar), the division occurs in a specific orientation due to the presence of structures like a whip-like tail. Multiple Fission: It is observed in organisms like the malarial parasite Plasmodium. The organism divides into many daughter cells simultaneously.
Fragmentation in Microbial Asexual Reproduction	Fragmentation is a form of asexual reproduction where an organism breaks into fragments, and each fragment develops into a mature, fully-grown individual. Fragmentation in Simple Multicellular Organisms: In multicellular organisms with basic body organisation, like Spirogyra, simple reproductive methods such as fragmentation are effective. Upon maturation, Spirogyra breaks into smaller fragments. These fragments then grow into new individual organisms.
Regeneration in Microorganisms and the intricate mechanisms behind new individual formation	Regeneration is the ability of fully differentiated organisms to develop into new individuals from their body parts. Regenerative Abilities of Organisms: Many organisms can regenerate or grow into complete beings from their body fragments. For instance, simple animals like Hydra and Planaria exhibit this ability. If these animals are cut or broken into multiple pieces, each fragment has the potential to grow into a complete organism. Mechanism of Regeneration: Regeneration is facilitated by specialised cells. These cells undergo proliferation, creating a large number of cells. From this collective cell mass, differentiation occurs, where cells transform into various cell types and tissues. This transformation process, where cells follow an organized sequence to form different tissues, is termed development.
Budding: Asexual Reproductive process in Hydra and the emergence of independent organisms	Budding is a form of asexual reproduction in which a new organism develops from an outgrowth, or bud, due to cell division at one particular site on a parent organism. Budding Process in Hydra: Hydra is an organism that utilizes regenerative cells for reproduction through budding. A bud emerges as an outgrowth on the hydra due to consistent cell division at a specific location. These buds grow and evolve into small, individual organisms. Upon reaching maturity, these buds detach from the parent organism and transform into new, independent individuals.

Difference between regeneration and reproduction
Criteria	Regeneration	Reproduction
Definition	Growth of an organism from a fragment of its body.	Natural process of producing offspring.
Dependence on Fragmentation	Yes (organisms can grow from their body fragments).	No (organisms typically don’t rely on being fragmented).

Story of Dolly, the First Cloned Mammal

Cloning refers to the production of an exact replica of a cell, a specific living part, or an entire organism.

Dolly’s Historic Birth

Dolly, a sheep, holds the distinction of being the first mammal to be cloned.
She was born on 5th July 1996, a significant achievement by Ian Wilmut and his team at the Roslin Institute in Edinburgh, Scotland.

Process of Cloning Dolly

A cell was extracted from the mammary gland of a Finn Dorsett sheep.
Concurrently, an egg was taken from a Scottish blackface ewe.
The nucleus of this egg was removed and replaced with the nucleus from the Finn Dorsett sheep’s mammary gland cell.
This modified egg was then implanted into the Scottish blackface ewe.
Dolly developed from this egg, and although she was born by the Scottish blackface ewe, she was genetically identical to the Finn Dorsett sheep.

Significance and Legacy of Dolly

Dolly did not exhibit any traits of the Scottish blackface ewe, demonstrating the complete genetic influence of the Finn Dorsett sheep.
Dolly lived a relatively normal life, producing offspring through regular reproductive means.
Unfortunately, she passed away on 14th February 2003 due to a specific lung ailment.

Cloning Post-Dolly

Following the success of Dolly, numerous efforts have been undertaken to clone other mammals.
However, many of these cloned animals either perish before reaching full term or shortly after birth.
Notably, many clones have manifested severe abnormalities, indicating the challenges and complexities inherent in the cloning process.