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Reproduction

Bacteria reproduce by two methods

  1. Asexual reproduction
  2. Genetic recombination

1. Asexual reproduction

(i) Binary fission -

  • This is the most common method of bacterial reproduction. Binary fission takes place by amitosis. (Amitosis is characteristic of prokaryotes. Mitosis and Meiosis never occur in prokaryotes. )
  • First of all DNA replication takes place in bacterial cell. Under favourable conditions the bacterial cells divide into two cells due to formation of transverse septum in the centre of the cell. Each daughter cell grows into a new bacterium.
  • Under favourable conditions, the cells of bacteria divide after every 20 minutes.
Image showing binary fission.

Image Showing Binary Fission.… (630 more words) …

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Heterotrophs

  • Most of the bacteria are heterotrophic i. e. , they cannot manufacture their own food.

  • They receive their own food from dead organic matter or living organism.

These are of following types

  1. Saprotrophic bacteria - These bacteria obtain food from dead and decaying organic matter.

    These are of two types

    1. Obligate saprotrophic - These bacteria obtain food only from dead organic matter.

      These are completely saprotrophs

      e. g. Bacillus vulgaris, Clostridium botulinum

    2. Facultative parasite - These are normally saprophytic in nature, but in the absence of dead organic matter they can become parasitic.

    e. g. Pseudomonas, Staphylococcus

  2. Parasitic bacteria -… (87 more words) …

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