Binary Fission

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Binary fission
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What is Binary Fission?

• Binary fission is a type of asexual reproduction
  where a parent cell divides, resulting in two
  identical cells, each having the potential to
  grow to the size of the original cell.
• In the process of binary fission, an organism
  duplicates its genetic material, or
  deoxyribonucleic acid (DNA), and then divides
  into two parts (cytokinesis), with each new
  organism receiving one copy of DNA.
• Binary fission is the primary method of
  reproduction of prokaryotic organisms.

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Types of Binary Fission

• In protists, binary fission is often
  differentiated into types, such as transverse or
  longitudinal, depending on the axis of cell
  separation.
• Regular transverse fission in some organisms,
  such as tapeworms and scyphostome polyps, is
  called strobilation.
• A few metazoan (multicellular) species regularly
  undergo a body division into several units
  simultaneously, a process called fragmentation.
  Planarian fission and fragmentation generally
  represent direct reproduction in which each
  portion regenerates missing parts to become a
  complete new animal.

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Binary Fission in Bacteria

• The process of binary fission is usually rapid,
  and its speed varies among species.
• The time required by bacteria to double the
  number of cells it has is called doubling time.
• Furthermore, each species requires specific
  conditions for its growth.
• These conditions include pH levels, temperature,
  oxygen, light, moisture, osmotic pressure.
• For instance, mesophiles thrive at moderate
  temperatures ranging from 20 C to 45 C. The
  ambient temperature of the human body is 37 C,
  which means many of the disease-causing bacteria
  are mesophiles.

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Steps involved in the binary fission in bacteria

• Step 1- Replication of DNA
• The bacterium uncoils and replicates its
  chromosome, essentially doubling its content.

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Steps involved in the binary fission in bacteria

• Step 2- Growth of a Cell
• After copying the chromosome, the bacterium
  starts to grow larger in preparation for binary
  fissions. It is followed by an increase in
  cytoplasmic content. Another prominent trait of
  this stage is that the two strands migrate to
  opposite poles of the cell.

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Steps involved in the binary fission in bacteria

• Step 3-Segregation of DNA
• The cell elongates with a septum forming at the
  middle. The two chromosomes are also separated in
  this phase.

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Steps involved in the binary fission in bacteria

• Step 4- Splitting of Cells
• A new cell wall is formed at this phase, and the
  cell splits at the centre, dividing the parent
  cell into two new daughter cells. Each of the
  daughter cells contains a copy of the nuclear
  materials as necessary organelles.

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