exam qs (biodiversity)

• the scottish wildcat can interbreed successfully with domestic cats

  explain how the effect this could have on the genetic diversity of the Scottish wildcat

  increases size of gene pool

  because of introduction of new alleles
• presence of a cell wall in eukaryota? yes, no or some

  some
• allele - alternative form of a gene
• use the hardy-weinberg equation to show that more than 50% of the forest elephant population are homozygous for the GBA gene

  freq of allele in forest elephant = 0.43 and 0.57

  p^2 + 2pq + q^2 = 1

  p^2 and q^2 = 0.43^2 and 0.57^2 = 0.185 and 0.325 respectively

  0.185 + 0.325 = 0.51

  freq = 51% (greater than 50%)
• SGSV is a seed bank

  seeds from 3 varieties of maize were tested to see the effects of long periods of storage

  explain how SGSV could make use of these results

  seeds that have been kept for long periods will not be useful

  diff types of seed lose viability at diff rates

  therefore regular testing is needed (to ensure seeds are still viable)
• explain how breeding programmes in zoos maintain the genetic diversity of captive populations

  they exchange animals between zoos

  they use a stud book to keep a record of all breeding events

  animals are selected to prevent breeding between closely related individuals
• state suitable conditions for keeping seeds in a seed bank

  cold dry area
• many different types of anti freeze protein are produced by ray-fin fishes

  analyse the data to explain when these ray-fin fish are likely to have evolved the ability to produce anti-freeze proteins

  anti-freeze proteins are advantageous only when there is sea ice

  so anti-freeze proteins are likely to have increased in freq during an ice age

  the only ice ages since the existence of the ray-fin fish are the quaternary and karoo

  therefore ray-fin fish producing anti freeze proteins are likely to have evolved in the last 2.6 million years