10 investigating diversity

what does genetic diversity refer to?

the variety of alleles within or between species

how can genetic diversity be assessed?

by comparing:

• the frequency of measurable or observable characteristics (e.g. flower colour)

• the base of DNA, which provides a direct measure of genetic differences

• the base sequence of mRNA, which reflects the DNA coding sequence that has been transcribed

• amino acid sequence of proteins, which results from translation of the mRNA and reflects genetic differences at the functional level

which methods are the most reliable for investigating diversity?

comparing the base sequence of DNA and mRNA

why isn’t comparing the frequency of measurable or observable characteristics a less reliable method for investigating diversity?

characteristics may be influenced by environmental factors as well as genes

why are samples taken when measuring variation within a population?

it’s too time consuming and impossible to record data on every individual within a population

how is an investigation into variation carried out scientifically?

• data should be collected using random sampling to avoid bias

• take large samples to ensure results are representative of the population

• a mean is calculated to summarise the data

• the standard deviation is calculated to show the spread of values around the mean, which helps assess how much variation exists

• statistics and standard deviation values can be used to interpret and compare whether the variation between groups is significant