biological approach

• 4 main parts to the biological approach

  1=the influence of genes on behaviour

  2=the influence of the brain on behaviour

  3=the influence of neurochemistry on behaviour

  4=evolution and behaviour
• genes 


  bits of DNA which make proteins - cause physiological responses in the body

  carry instructions for the developments of a certain characteristic
• genetics 


  heredity - traits and characterises inherited from parent/ancestors

  genetics - is the study of how genes influence physical and behavioural characteristics
• heritability 


  extent to which genetic individual differences contribute to individual differences in observed behaviour

  the more a trait is influences by genetic factors, the greater its heritability
• genotype vs phenotype 


  Geno - whole set of genetic info carried by organism

  pheno - physical manifestation (appearance) of genotype
• recessive vs dominant genes

  recessive only shows if the individual has 2 copies of recessive allele

  dominant always shows even if the individual only has 1 copy of allele
• influence on the brain

  largest part = cerebrum, , 85% of total mass of the brain. outer surface of cerebrum is called cerebral cortex - responsible for higher order functions (thought and language)

  cerebrum is divided into 2 halves = hemispheres , each hemisphere is divided into 4 different parts = lobes
• the influence of neurochemistry

  neurotransmitters are chemicals in the brain, when released they trigger nerve impulses which stimulate the brain
• evolution 


  over time animals adapt to their environment , leads to a change over successive generations in the genetic make up of the animal , natural selection is one way evolution occurs
• natural selection


  individuals within a species differ from each other

  individua must compete for resources

  those who survive this competition will have characteristics and behaviours that are more likely to lead to survival - these behaviours are then passed on to their offspring and become widespread in the population
• sexual selection 


  traits evolve because they were attractive to the opposite sex

  this increases reproductive success (more offspring) and will leaf to survival of the genes into the next generation
• strength 


  its scientific , explanations are based on biological facts which is scientific and objective - means the theories within biological approach are falsifiable
• weakness 


  reductionist

  reduces complex human behaviour down to simplistic biological processes , ignoring the role of other factors

  more likely behaviour is determined by an interaction of both genes and environment - idea known as the diathesis stress-model
• strength 


  real life application - knowledge of neurotransmitters has led to effective treatments fir mental illness - shows approach has positive implications
• weakness


  deterministic , suggests that an individuals behaviour is shaped or controlled by internal forces with no freewill - saying behaviour id caused by genetics is often used as an excuse for undesirable behaviour - socially insensitive