Investigating Genetic Diversity Flashcards
how can genetic diversity be investigated?
- the frequency of measurable or observable characteristics
- the amino acid sequence of the proteins encoded by DNA and mRNA
- the base sequence of DNA
- the base sequence of mRNA
why is sample size important?
if the sample size is small , the results may not be representative of the population
how would you avoid/prevent sampling bias + describe a method ?
Random sampling
- divide study area into a grid of numbered lines
- use random numbers to obtain a series of coordinates
- take samples at the intersection of each pair of coordinates
what are the benefits of using a large sample size
- there is a smaller probability that chance will influence the results
- statistical tests are able to be carried out to analyse the data collected
what is intraspecific variation?
the variation between organisms of the same species
(same species possesses the same genes but not necessarily the same alleles)
what is interspecific variation?
the variation between organisms of different species
how would you use variation in the DNA/mRNA or amino acid sequence of organisms to investigate relation/genetic diversity?
- the more similar the DNA, mRNA or amino acid sequence is between two organisms, the closer related they are to each other
- this is because there has been less time for mutations to occur and build up if they come from a recent common ancestor
why is comparing DNA sequences preferred to comparing Amino Acid sequences?
- the degeneracy of the genetic code means the same amino acid can be coded by different base triplets
- eukaryotic DNA contains introns that can also be compared
why is comparing mRNA base sequences sometimes preferred to comparing DNA base sequences ?
it is sometimes easier to isolate the mRNA from cells than DNA
