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History of genetics
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Learn introductory genetics with Braimy- B.Sc agriculture
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a) Binary Fission:

  • In binary fission, a single bacterial cell divides into two daughter cells. At first, the bacterial cell reaches critical mass in its form and cell components.
  • The circular double-stranded DNA of the bacteria undergoes replication and new complementary strands are formed.
  • These two strands of DNA are then moved to the different poles of the cell and a transverse septum then takes place and develops in the middle region of the cell which separates the two new daughter cells and thus binary fission I completed.
  • It is a rapid process and takes minutes to complete.

Binary fission of bacteria - YouTube

b) Conidia Formation:

  • The formation of conidia takes place in filamentous bacteria such as Streptomyces through the formation of a transverse septum at the apex of the filament.
  • The part bearing the conidia is called the conidiophore and after it is detached from the mother cell, in a suitable substratum it germinates giving rise to new mycelium.
  • This type of asexual reproduction is also called fragmentation.

How To Draw Penicillium Diagram | Diagram of Conidia in Penicillium in Very  Simple & Easy Way - YouTube

c) Budding:

  • In this method of reproduction, the bacterial cell develops a small swelling at one side which continuously increases in size.
  • At the same time, the nucleus also undergoes division where one part with some cytoplasm enters the swelling and the other part remains with the mother cell.
  • The outgrowth is called the bud and it eventually gets separated from the mother cell by a partition wall. This method of reproduction also comes under vegetative reproduction in bacteria.
  • Example: Rhodomicrobium vannielii

Budding Cells - Fungi, Plants, Bacteria, Yeast, and Hydra

d) Cysts:

  • Cysts are formed by the deposition of additional layers around the mother cell and are the resting structure during unfavorable conditions.
  • When conditions are favorable again, the mother cell behaves like its normal self again. Example: Azotobacter.

Characterization of cyst cell formation in the purple photosynthetic  bacterium Rhodospirillum centenum. | Semantic Scholar

e) Reproduction through endospore formation:

  • Endospores in a bacterial cell are formed during stressful conditions such as desiccation and starvation.
  • They contain a central protoplast, and a core consisting of DNA, ribosomes, enzymes and the t-RNA, everything necessary for the formation of a new cell.
  • Only one endospore is formed in one bacterial cell and on germination, it gives rise to a new bacterial cell.

Endospore formation in bacteria | Structure of endospore | endospore forming  pathogenic bacteria - YouTube

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