Cell Division: Meaning and Definition, Types of Cell Division, Mitosis (For CBSE, ICSE, IAS, NET, NRA 2022)

Get unlimited access to the best preparation resource for competitive exams : get questions, notes, tests, video lectures and more- for all subjects of your exam.

Meaning and Definition of Cell Division

  • Cell division is the process by which a parent cell divides into two or more daughter cells.
  • It occurs as a part of a larger cell cycle.
  • Each parental cell gives rise to the two daughter cells.

Types of Cell Division

Mitosis

  • Exact replicas are made by the process cells.
  • This is observed in all the body՚s cells that includes eyes, skin, hair, and muscle cells.

Meiosis

  • Sperm or egg cells are produced instead of identical daughter cells in this type of cell division.
  • Meiosis results in four haploid daughter cells by undergoing one round of DNA replication.
  • In Meiosis-I, the homologous chromosomes are paired and then separated and distributed into daughter cells.
  • In Meiosis-II, the chromatids are separated.
  • In case of human՚s meiosis gives rise to gametes and is also known as gametic meiosis.
  • In case of plants, meiosis is called sporic meiosis i.e.. the meiosis gives rise to kind of spores that germinates into haploid vegetative phase (gametophyte) .

Binary Fission

  • The division of a single entity into two or more parts including the regeneration of those parts to separate entities resembling the original.
  • Taking example of a single celled organisms like bacteria which replicate themselves for reproduction.

Eukaryotes

  • Eukaryotes are those organisms whose cells have a nucleus enclosed within a nuclear envelope.
  • A vegetative division and a reproductive cell division are the two distinct types of cell division.
  • In a vegetative division each daughter cell is genetically identical to the parent cell (mitosis) .
  • In a reproductive cell division, the number of chromosomes in the daughter cells is reduced by half to produce haploid gametes (meiosis) .
Forms of Mitosis of Karyokinesis Step in Eukaryotes
Forms of Mitosis of Karyokinesis Step in Eukaryotes

Prokaryotes (Bacteria and Archaea)

  • A prokaryote is that cellular organism which lacks an envelope-enclosed nucleus.
  • Usually undergo a vegetative cell division known as binary fission.
  • For most of the prokaryotes, binary fission is the means of division apart from alternative manners of division, such as budding.
  • Budding is defined as a type of asexual reproduction in which a new organism develops from an outgrowth or bud due to cell division at a site.
Simple Unicellular Microorganisms
  • One cell division is equivalent to reproduction i.e.. an entire new organism is created as in case of amoeba.
  • Mitotic cell division can create progeny (Collective offspring may be known as a brood or progeny) from multicellular organisms.
  • From the one-celled zygote, mitotic cell division enables sexually reproducing organisms to develop.
  • The human body experiences about 10 quadrillion cell divisions in a lifetime.
Simple Unicellular Microorganisms

Cell Division in Bacteria

  • The cell division happens through binary fission or budding.
  • The divisome is a protein complex in bacteria.
  • This is responsible for cell division, constriction of inner and outer membranes during division, and peptidoglycan (PG) synthesis at the division site.
Cell Division in Bacteria

Developed by: