Asexual%20Reproduction

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Asexual Reproduction
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Asexual Reproduction

• Mitosis is the basis of asexual reproduction
• Involves only one parent individual
• Results in genetically identical offspring
• Clones

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Advantages

• Safe
• Dont need to find a mate
• Can give loads of offspring quickly

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Disadvantage

• All offspring genetically identical
• If environment changes in some way then
• could cause complete of a population

destruction
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Strategies for Asexual Reproduction

• Binary Fission
• Sporulation
• Regeneration
• Budding
• Vegetative Propagation
• Most important on WJEC

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Binary Fission

• Mitosis followed by splitting of the individual
• Only in the most simple of organisms
• Bacteria and Protoctists

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Sporulation

• Mitosis followed by the production of asexual
  spores
• Spores can survive adverse conditions
• Good for dispersal
• Fungi and lower plants (mosses / ferns)

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Regeneration
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Regeneration

• Rather Dramatic!
• Lizards shed tails
• Starfish can grow from only one arm!

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Budding

• Outgrowth from parents
• Produces miniature of parent
• This bud then drops off the parent and is
  independent.

Yeast
Hydra
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Vegetative Propagation

• Sophisticated version of budding that occurs in
  plants.
• May involve perennating organs
• bulbs, corms etc where stored food means can be
  dormant over winter

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Parthenogenesis

• Virgin birth!
• 70 species of vertebrates
• New Scientist Short Sharp Science Blog