Edexcel IGCSE Biology 復(fù)習(xí)筆記 4.2.3 Food Pyramids & Transfer of Energy Food Pyramids A pyramid of numbers shows?how many organisms?we are talking about at each level of a food chain. Th...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 4.2.2 Food Webs Food Webs A?food web?is a network of interconnected food chains Food webs are more realistic ways of showing connections between organisms with...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 4.2.1 Trophic Levels & Food Chains Trophic Levels & Food Chains Trophic levels Trophic levels are used to describe the?feeding relationships between or...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 4.1.4 Abiotic & Biotic Factors Abiotic & Biotic Factors In Biology, ‘a(chǎn)biotic’ means non-living An?abiotic?factor is a?non-living?factor within an envir...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 4.1.3 Biodiversity Biodiversity Biodiversity is the?range and variety of different species?of organisms on?Earth, or within an?ecosystem It considers not only ...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 4.1.2 Practical: Investigating Population Size Practical: Investigating Population Size Ecology?is the branch of biology that studies: The?distribution?...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 4.1.1 Key Terms in Ecology Key Terms in Ecology There are several key terms that we use when referring to the various different components of an ecosystem and ...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 3.2.8 Natural Selection Darwin's Theory of Evolution by Natural Selection Charles Darwin proposed the?theory of evolution by natural selection He came up with this th...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 3.2.7 Mutation Mutations Mutations are?rare,?random changes?that occur in the?sequence of DNA bases?in a gene or a chromosome Mutations occur?continuously As t...
