Biological

Cards (51)

  • What are the assumptions of the Biological Approach?
    Genetic determinism, biological basis of behavior, and the influence of evolution.
  • What is the biological Approach?
    explanation of our behaviours mainly in terms of biological factors
  • How long has the biological study of the brain and behaviour been going on?

    In parallel with the history of experimental psychology
  • Understanding Genetics
    The body is made up of cells and each cell contains 23 pairs of chromosomes
  • What does DNA stand for?
    Deoxyribonucleic acid
  • What is DNA?
    • the substance that chromosomes are made of
    • a chain of two or more nucleotides joined together
  • each cell in your body has the exact same DNA
  • What is a gene?
    A gene is a segment of DNA that contains the production of one specific protein.
    • control our physical traits
  • Animals of the same species broadly have the same set of genes, and different species have different sets of genes.
  • What do we call different versions of a gene?
    Alleles
  • if there is different versions of a gene (alleles) we say there is genetic variation in that characteristic e.g. hair colour.
  • what are sex cells?
    • either a sperm or egg
    • have 23 chromosomes
  • What occurs in reproduction?
    Where a males sex cell (sperm) meets a women's sex cell (eggs) to form a new cell that has 46 chromosomes
  • what is genetic inheritance?
    when traits are passed down from parent to child
  • what is a genotype?
    A description of all of the genes and alleles in a body
  • what is a phenotype?
    The observable characteristics or behaviours of a person (physical traits)
  • Genotype + environment = phenotype
  • What do we call Environmental factors?
    things in the environment can affect our physical traits e.g. sun
  • behaviours and psychological traits are partly inherited
  • To sum up, the biological approach studies the extent to which behaviours are determined by genetics and genes determine behaviour by affecting processes inside the brain.
  • Environmental factors have a bigger impact on behaviour than they do on physical traits
  • What are the two types of twin?
    MZ / Mono-zygotic (same genotypes, 100%)
    DZ / Di-zygotic (different genotypes, 50%)
  • What type of twins are Monozygotic?
    identical twins
  • What type of twins are dizygotic?
    un-identical twins
  • Monozygotic twins come from one Zygote, which splits into two identical zygotes, whereas dizygotic twins come from two different zygotes.
  • Both monozygotic and dizygotic twins have some shared and some non-shared environments
  • The concordance rate is how often we see a trait or disorder within a group of people who share genes compared with those who do not share genes.
  • Concordance rates for MZ twins tend to be higher than for DZ twins because they share more genetic material.
  • Assumptions
    • Both MZ and DZ have a similar amount of shared environment
    • Shared environment has a similar impact on phenotype
  • What is a shared environment?
    the environment that a pair of twins share in common.
  • what is a non-shared environment?
    the environment that a pair of twins don't share in common.
  • what do we say for twins that have the same phenotype?
    concordant
  • In twin study's, we don't include sets of twins where neither twin has the trait we're studying.
  • what is the concordance rate?
    The percentage of twins who share a characteristic, given that at least one twin has the characteristic.
  • Genetic variation contributes to a trait if....
    the concordance rate for monozygotic twins is bigger that the concordance rate for dizogotic twins
  • The bigger the difference in concordance rates between monozygotic and dizygotic twins, the more influence genetic variation has on the trait.
  • In 1996, McGuffin performed a twin study on the presence of depression in twins
  • McGuffin found that if one monozygotic twin had major depression, there was a 46% chance the other twin had depression too. They had a concordance rate of 46%.
  • For Dizygotic twins, McGuffin found that if one twin had major depression, there was a 20% chance that the other twin did too, having a concordance rate of 20%
  • McGuffin could conclude genetic variation does contribute to depression because the concordance rate was bigger for monozygotic (46%) than dizygotic (20%) twins.