Download Reproductive Strategies

Reproductive Strategies
Asexual Reproduction
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Def: Repro not involving genetic exchange
between organisms
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No gametes involved
No genetic variety between generations
Examples: budding, binary fission,
fragmentation
Asexual Reproduction
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Advantages

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No need to find a mate (good for solitary
animals)
Can make many babies fast (opportunistic)
Disadvantages
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No variety, not very adaptable
Sexual Reproduction
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Def: involves fusion of gametes to form
offspring
Hermaphrodites
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Def: individuals can produce both eggs
and sperm
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Advantages
Each individual encountered is a potential mate
 Twice as much reproductive potential
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Disadvantage
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Cost lots of energy to produce both eggs and
sperm
Sequential Hermaphrodites
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Reverses sex during lifetime
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Ex. Whiptail lizards
Wrasse
Mechanisms of Reproduction
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External fertilization: takes place in the
environment
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Environment must prevent gametes drying up
and overheating
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Timing must be perfect

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WATER
Behaviorally or environmentally cued
Eggs and zygotes are not cared for (and good
food)

Produce MANY
Mechanisms of Reproduction
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Internal Fertilization: sperm deposited in
or near female reproductive tract
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Often produce fewer zygotes
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Protected and cared for
Amniotic eggs
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Look up: what animals have them (3
animal classes)?
How are they an adaptation for life on
land?
Make a labeled diagram, and include the
purpose of each structure (p819)