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'.

All Topic 3 Sub-topics A3.1: Diversity Of Organisms (HL)A3.1: Further diversity (HL)A3.2: Classification & cladistics B3.1: Gas Exchanges (HL)B3.1: Further gas exchange B3.2: Transport (HL)B3.2: Further transport (HL)B3.3: Muscle & motility C3.1: Body Systems (HL)C3.1: Plant systems C3.2: Defence Against Infectious Disease D3.1: Reproduction (HL)D3.1: Further reproduction D3.2: Monogenic Inheritance (HL)D3.2: Polygenic inheritance D3.3: Homeostasis (HL)D3.3: Further homeostasis

external fertilization

The fusion of an egg and sperm outside the body, such as in fish and frogs

fertilization

The fusion of an egg and sperm

fetus

An embryo that has developed skeletal tissue by 8 weeks

gamete

Sex cell

internal fertilization

The fusion of an egg and sperm inside the body, such as in humans

oogenesis

The production of female gametes in the ovaries, commencing in puberty and lasting until the eggs are run out

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

spermatogenesis

The production of male gametes in the testes, commencing during puberty and lasting indefinitely

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