Preview of the note
1) Definition of cell division
2)Factors affecting cell division
3) Importance of cell division
It's quite interesting to know that every large or minute organisms that we see around us are made of minute units called cells. But have you ever thought this minute unit has its own cycle
Well, Cell division is one of its cycle, Cell division refers to the means of reproduction by which mature cells divides and forms new cells which may or may not resemble mother cells in its characters.It was first studied by Prevost and Dumas (1824 AD) in zygote of frog.
There are major three types of cell divisions :
Factors affecting cell division
Cell size: A metabolically efficient cell has high nucleocytoplasmic ratio(i.e.the ratio of volume of nucleus to the volume of cytoplasm).Increase in size lowers the ratio. Hence to regain its metabolic efficiency cell undergoes division
Kernplasma or Karyoplasmic ratio :Rise in cell volume disturbs Kernplasma ratio, it stimulates cell to divide.
Mitogens: Mitogen are the agents or substances that trigger cell division.The common mitogen hormone in plant is is cytokinin. There are several mitogenic substances known in human beings like lymphocytes, EGF( Epidermal Growth Factor), PDGF( Platelet derived Growth Factor) which stimulates cell to initiate it's division.
Importance of Cell division
1) It plays a great role in Growth and development of zygote into adult.
2) Mitosis keeps the chromosome number constant and provide genetic stability to daughter cells.
3)Cell division keeps a check on cell size as overgrown cell is induced to divide.
4) Meiosis is the major facilitator for the production of continuous type of variations which helps organisms to fight against natural selection.
5) Cell division provides new cells for repair and regeneration of lost parts and healing of wounds.
Thus, cell division is important from various aspects.