IB Biology D3.1 Definitions
This page contains our IB Biology definitions for D3.1. By learning each one of these definitions, you will fully cover the content for IB Biology 'Further reproduction'.
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external fertilization
The fusion of an egg and sperm outside the body, such as in fish and frogs
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fertilization
The fusion of an egg and sperm
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fetus
An embryo that has developed skeletal tissue by 8 weeks
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gamete
Sex cell
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internal fertilization
The fusion of an egg and sperm inside the body, such as in humans
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oogenesis
The production of female gametes in the ovaries, commencing in puberty and lasting until the eggs are run out
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polyspermy
The fertilization of an egg by more than one sperm, which increase chromosome number, usually resulting in cell death or birth to sterile offspring
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spermatogenesis
The production of male gametes in the testes, commencing during puberty and lasting indefinitely
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