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Fragmentation can be defined as the process in which a larger fragment gets broken into smaller parts or chunks. It is an asexual form of reproduction which is seen processes such as DNA cloning and apoptosis. Fragmentation is seen happening in multicellular organism.
When a living organism gets broken into smaller pieces which are similar to the actual one is called as Fragmentation, in reproductive biology. Those broken parts are termed as fragments. The broken fragments again reassembles after its life cycle is completed and grows out as an adult that has the same shape, size and other characteristic similar to the parent.
What is Fragmentation?
The fragmentation process can happen due to natural as well as due to man made issues created. Example of fragmentation happening naturally is inappropriate climate conditions or stress from the outer environment can lead to fragmentation happening and those would further develop into adults that are identical to the parent.
Fragmentation can be seen in animals such as sponges, sea stars, worms, and plants such as fungi, lichens, molds and etc. A point to kept in mind that not the whole organism undergoes fragmentation but only a small part of it undergoes fragmentation to form a new organism.
Fragmentation is also called as splitting as the organism loses its part which gets broken into smaller fragments and later after maturing forms and adult, identical to the parent cell.
What is Reproduction?
Reproduction can be defined as the process in which a new organism is formed from the parent organism. Reproduction can be of two types, sexual and asexual reproduction.
Sexual reproduction occurs when two parent mate to produce an offspring is called as sexual reproduction. The male gives the sperm whereas the females give the egg which gets fertilized and a zygote is formed which then matures to an embryo which will further form into an adult.
Some other types of sexual reproduction are allogamy, autogamy and external fertilization.
In asexual reproduction only one parent is responsible for the formation of an offspring. Examples are budding, binary fission, fragmentation and parthenogenesis. When a single bacterium is divided into two it is called as binary fission.
Formation of tiny organs within the parent’s body and after some time it separates out is called as budding. Examples are amoeba, paramecium, yeast and etc. parthenogenesis is seen occurring in fishes, amphibians and reptiles.
Fragmentation is an asexual mode of reproduction, where a part of the parent organism get detached and further grows into a matured adult, upon the completion of cycle.
Example are sponges, flatworm – planaria. During the fragmentation process organism’s body is splitted which forms the daughter cell.
Fragmentation and Regeneration
Fragmentation is when a part of the organism is detached from the parent, maturing into an adult. This is called as fragmentation. Regeneration is when the broken fragment tends to regrow the part which was lost. In fragment new organism is formed whereas new organs are formed in regeneration. Only few organisms have the ability to undergo fragmentation but regeneration is possible by all organism.
a) Requires only a single parent.
b) The time taken by the juvenile to turn into a mature adult is quite less. Thus, less time consuming.
c) The number of offspring after fragmentation is quite huge.
d) Fragmentation can take place in varying climatic condition.
e) Maintains homeostasis.
a) Since in fragmentation the offspring is formed from one parent, thus, the genes and the characteristics would also come from one parent which decreases the genetic biodiversity.
b) As the same traits have been passed on from various generation, thus the same disease genes will be inherited thus, increasing the extinction chances.
c) With less biodiversity, the chances to stand against the attackers and to survive would be minimal, thus, they might get extinct.
d) Large number of offspring from one parent.
a) Algae and Fungi: Usually fragmentation is majorly seen in lichens and fungi. Asexual fragmentation is seen in yeast, mushroom, smuts, molds and others. A special structure seen in fungi are the hyphae which are the branched structures and from them exist the mycelium. When hyphae are young, they procure food from the fungi. When it matures, it can reproduce and procure food on its own. Examples of algae that undergo fragmentation are Spirogyra.
b) Plants: Vegetative fragmentation is seen in plants. As plants produces new roots and new shoots, through the dispersion of stolon from ferns and perennial trees the colony diameter is increased. Thus, once the root is separated it grows on it own to form a new root system. The other examples are:
1. Woody Plants: Example are sheds, twigs and willows, which grows into a new plant. The shedding of twigs naturally is called as cladoptosis.
2. Detachment from the parent plant is also seen in non woody plants such as Kalanchoe daigremontiana. The plants fall off and occupy the ground where they form new plant.
3. Nonvascular plants examples are the liverworts, mosses which produce through fragmentation produces gemmae which fall off and become a new plant.
c) Animals: In animals it is seen in corals, which are hard and soft and can be fragmented. Examples are Euphyllia, Acropora, Caulstrea and Pocillopora. Other animals are sea anemone, starfish and nematodes.
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