IB Biology B3.1 Definitions

This page contains our IB Biology definitions for B3.1. By learning each one of these definitions, you will fully cover the content for IB Biology 'Further gas exchange'.

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

Allostery

A structural change in haemoglobin when oxygen binds to one of its haem groups, increasing the affinity of the other subunits for oxygen

Bohr Shift

The change in the oxygen dissociation curve due to variations in pH, carbon dioxide levels, and temperature, affecting haemoglobin's oxygen affinity

Cooperative Binding

The phenomenon where the binding of oxygen to one haemoglobin subunit increases the affinity of the other subunits for oxygen

gas exchange

The process of oxygen and carbon dioxide diffusing across the walls of the alveoli

Myoglobin

A protein in muscle tissue composed of one α chain with one haem group, having a higher affinity for oxygen and storing it for muscle respiration

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