Estimating the Size of a Population Measuring all the different levels of biodiversity within an ecosystem could be very time consuming Finding out which species live in an ecosystem and the...
Edexcel IGCSE Biology 复习笔记 2.7.2 Leaf Structure Leaf Structure The structure of the leaf is adapted to carry out both photosynthesis and gas exchange The different cell types (palisade m...
Carrying Capacity The maximum stable population size of a species that an ecosystem can support is known as the carrying capacity Every individual within a species population has the potenti...
Edexcel IGCSE Biology 复习笔记 2.7.1 Diffusion in Gas Exchange Diffusion in Gas Exchange Diffusion is the movement of molecules from a region of its higher concentration to a region of its l...
Abiotic & Biotic Conditions Niche The place where a species lives within an ecosystem is its habitat The role that a species plays within its habitat is known as its niche, including: Th...
Edexcel IGCSE Biology 复习笔记 2.6.3 Practical: Investigating Respiration Practical: Investigating Respiration We can investigate the production of carbon dioxide and heat from respiration through ...
Practical Skill: Investigating the Effects of Random Sampling on Allele Frequencies Investigations to mimic the effects of random sampling on allele frequencies in a population can be devised using...
Edexcel IGCSE Biology 复习笔记 2.6.2 Types of Respiration Aerobic Respiration Aerobic respiration requires oxygen It is defined as the chemical reaction in cells that uses oxygen to break down nutr...
Allopatric & Sympatric Speciation Evolution causes speciation: the formation of new species from pre-existing species over time, as a result of changes to gene pools from generation to g...
