Sexual and Asexual Reproduction

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Sexual and Asexual Reproduction
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reproduction

• It is a biological process where the living
  organism produces new individuals of the same
  kind and thus, ensuring its continuity

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Asexual reproduction

• Asexual reproduction occurs by only one living
  organism.
• It mostly occurs in single-celled living
  organisms such as budding in a yeast and binary
  fission in Amoeba.

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Sexual reproduction

• Sexual reproduction occurs in most higher living
  organisms of plants and animals.
• It occurs through two living organisms, one of
  them is a male and the other is a female.

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First Asexual reproduction

• Asexual reproduction occurs in unicellular living
  organisms and some multicellular animals and
  plants where a living organism produces new
  individuals that have genetic traits identical to
  the parents.
• Asexual reproduction includes mitosis that does
  not require special systems or structures in the
  living organism.

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Types of asexual reproduction

• 1 Binary fission
• 2 Budding
• 3 Regeneration
• Spore propagation
• Vegetative propagation

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1 - Binary fission

• This type of division occurs in unicellular
  protozoans such as amoeba, paramecium and euglena
  and also in simple algae and bacteria.

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2 Budding

• Bud in yeast emerges as a lateral bulge in the
  cell then the cell nucleus is divided (mitosis)
  into two nucleuli.
• One of them remains
• in the parental cell and
• the other immigrates to the bud.

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3 - Regeneration

• Regeneration is the ability of animals to
  compensate their missing parts.
• The living organism can reproduce by one of its
  parts. Starfish arms could be revived and give
  out a complete animal
• if they contain a part of the
• central disc of the animal.

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4 - Spore propagation

• It is a type of asexual reproduction which is
  more common in some fungi such as bread mould and
  mushrooms. Fungi have special organs called
  sporangia
• When spores find a suitable
• environment, they starts
• growing to gives out
• a new organism.

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5 - Vegetative propagation

• plants reproduce vegetatively without needing
  seeds
• by their vegetative organs and the cells (tissues
  culturing) to produce new plants very similar to
  the parent plant
• From the above, you see that the asexual
  reproduction produces offspring identical to
• their parents. It is caused by (mitosis

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Second Sexual reproduction

• It is the type of reproduction in the higher
  living organisms.
• Sexual reproduction occurs between two parental
  individuals. One of them is a male and the other
  is a female.
• Sexual reproduction depends on two main
  processes
• formation of gametes and fertilization.

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Formation of gametes

• Gametes in organisms are formed of reproductive
  cells by the meiotic division (reduction
  division).
• Gametes resulted from this
• division contain
• (N) of chromosomes

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Fertilization

• It means the combination of the male
• gamete and female gamete to form a zygote
• This zygote contains genetic material from each
  parent
• The resulted offspring have new genetic traits
  that combine the parents traits.
• Thus, sexual reproduction is a source of genetic
  variation.

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