AQA A Level Biology复习笔记7.4.5 Ecosystems
Ecosystems are Dynamic Ecosystems Species do not exist by themselves in their own isolated environment, they interact with other species forming a community The species within a community in...
AQA A Level Biology复习笔记7.4.4 Estimating the Size of a Population
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...
AQA A Level Biology复习笔记7.4.3 Carrying Capacity
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...
AQA A Level Biology复习笔记7.4.2 Abiotic & Biotic Factors
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...
AQA A Level Biology复习笔记7.3.8 Investigating the Effects of Random Sampling on Allele Frequencies
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...
AQA A Level Biology复习笔记7.3.7 Types of Speciation
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...
AQA A Level Biology复习笔记7.3.6 Reproductive Separation
Reproductive Separation Reproductive separation In order for evolution to occur the new species population must be genetically and reproductively separated from the pre-existing species popu...
AQA A Level Biology复习笔记7.3.5 Evolution
Evolution The allele frequencies (within the gene pool) of a population can change over time due to processes such as natural selection When the allele frequencies of a population change suf...
AQA A Level Biology复习笔记7.3.4 Types of Selection
Types of Selection & Their Effects Environmental factors that affect the chance of survival of an organism are referred to as selection pressures For example, there could be high levels ...
