10 - Biodiversity

• What is the definition of a species?

  A group of similar organisms that can interbreed to make fertile offspring.
• What is courtship behaviour & give two reasons it is important?

  The different behaviours that animals demonstrate to attract a mate.

  It is important for

  • successful mating
  • species recognition.
• What is meant by the binomial system?

  Individuals are named after their genus and species, eg, Homo sapiens and humans.
• What is meant by a hierarchy (2 marks)?

  Smaller groups arranged within larger groups. There are no overlaps between groups
• A phylogenetic classification system arranges species into groups based on which two factors?

  1. Evolutionary origins
  2. Evolutionary relationships
• Fill in the name of each taxa:

  Domain

  Kingdom

  Phylum

  Class

  Order

  Family

  Genus

  Species
• The accuracy of classification & phylogenetic trees is improving due to advances in what?

  1. Immunology sequencing
  2. Genome sequencing
• What does the phylogenetic tree show you about the relationship between humans and chimpanzees?

  • Humans and chimpanzees share a recent common ancestor.
  • Humans are most closely related to chimpanzees.

  
• What is a habitat?

  The range of physical, biological, and environmental factors in which a species can live.
• What is species richness?

  The number of different species in a particular area at a particular time.
• What in the index of diversity?

  The relationship between the number of species in a community and the number of individuals in each species
• What is does the N & n represent in the index of diversity formula?

  • N = the total number of organisms of all the species
  • n= the population size 1 is the lowest value for D.
  • The larger the value for D, the greater the species diversity. It is typically between 1-10

  
• Farming techniques can reduce biodiversity. What are some farming practices which may decrease biodiversity?

  1. Destruction of hedgerows
  2. Selective breeding
  3. Monocultures
  4. Over-grazing
  5. Filling in ponds and draining wetlands
• What are some methods that can be used to compare genetic diversity with or between species?

  1. The frequency of measurable or observable characteristics
  2. the base sequence of DNA
  3. the base sequence of mRNA
  4. the amino acid sequence of the proteins encoded by DNA and mRNA.
• Why is comparing the DNA base sequence better than simply comparing observable features to determine genetic diversity (1 mark)?

  More accurate measurement
• Why do different species who are distantly related have very different DNA base sequences?

  Mutations will accumulate in the DNA of a species overtime, creating different alleles. The longer ago a species diverged, the more time for mutations to occur and therefore the more different the DNA base sequence.
• When measuring variation within a population, samples are taken. This is because it would be too time-consuming and potentially impossible to record data on every individual within a population. To ensure your sample is representative of the population you must take a large sample and to avoid bias you should randomly sample. By collecting a large sample, you can calculate a mean and do a statistical test to see if any differences of correlations you see are significant.
• What does this data showing the mean number of clovers found in different fields show?

  The difference in the means of sites A and B is not significantly different because the standard deviations overlap.