Biological approach

• The Somatic Nervous System transmits information received by the senses to the central nervous system and sends messages from the central nervous system to the muscles.
• The DNA on each chromosome carries the units of information called genes.
• The Peripheral Nervous System is made up of neurons that transmit messages or information to and from the central nervous system.
• The nucleus of every cell (apart from sex cells) contains 46 structures called chromosomes (23 pairs of chromosomes which have been inherited from their parents these are our genotype and form the basis for our development).
• Phenotype: This is the product of what happens when the genotype interacts with the environment.
• The central nervous system is made up of the brain and spinal cord.
• Chromosomes are made up of a complex chemical called DNA.
• In response to a signal from the brain, hormones are secreted directly into the bloodstream by the endocrine glands, where they travel to their “target cells” and exert their influence by stimulating receptors on the surface of or inside cells.
• Inhibitory neurotransmitters inhibit nerve impulses in order to calm the brain and balance mood.
• Examples of hormones include testosterone (male) and oestrogen (female).
• Natural selection occurs simply because some genetically inherited traits give the possessor certain advantages.
• Some hormones such as adrenaline are also classed as neurotransmitters.
• There are many different types of neurotransmitter s, some trigger the receiving neuron to send an impulse and some stop it from doing so.
• The effects of hormones are slow in comparison with the nervous system, but very powerful.
• Biological psychologists agree that genes influence behaviour.
• Serotonin is an inhibitory transmitter, adequate amounts of which are necessary to maintain a stable mood.
• The pituitary gland and adrenal glands are examples of glands.
• The main principle of the Evolutionary Theory of Behaviour is that any genetically determined behaviour that enhances an individual’s survival and reproduction will be passed on in the genes to future generations, i.e. be naturally selected.
• Many biological psychologists would accept that much of human behaviour depends upon an interaction between inherited factors (nature) and the environment (nurture).
• Neurotransmitters travel from one neuron to the next across a junction called a synapse.
• Excitatory neurotransmitters trigger nerve impulses in the receiving neuron and stimulate the brain into action.
• High levels of dopamine are related to schizophrenia.
• Hormones are biochemical substances that are produced by glands in the endocrine system.
• This aggressive behaviour is then passed on in the genes to its offspring.
• Dopamine is an excitatory neurotransmitter associated with our “drive” and motivation.
• Hormones are produced in large quantities but disappear very quickly.
• When a nerve impulse reaches the end of a neuron, a chemical called a neurotransmitter is released.
• Intelligence, psychological disorders and male and female differences are psychological characteristics that are thought to be influenced by genes.
• Neurotransmitters are seen as very important by biological psychologists as they are thought to affect behaviour.
• The transmission of these chemicals is via the cerebral fluid.
• The possessor is more likely to survive, reproduce and pass on these genes/ traits to future generations.
• Low levels of serotonin are related to depression.