The Biological Approach Flashcards
What are the assumptions?
psychology is a science and should be studied scientifically
brain and mind are same, we can study the mind by studying the brain
behaviours have an evolutionary basis; genes have adapted over many years
no genes for behaviours, genes synthesise proteins which affect behaviour
behaviours are influenced by heredity, genetics, biological structures, chemical processes and evolution
what is a genotype?
- actual genetic makeup.
- shown by 23 pairs of chromosomes.
- 50% is identical to our siblings and parents, but identical twins share 100%.
- dictates characteristics such as hair colour and eye colour
- someone is born with this
what is a phenotype?
- product of what happens when someone interacts with the environment
- e.g. height is a genotype, but nutrition and diet affects the likelihood of someone reaching that potential height
- can be physical, behavioural or psychological
what is a dominant gene?
controls expression of characteristics of both pairs are dominant or if one is recessive
what is a recessive gene?
only influences expression of a characteristic if both pairs of genes are recessive
what is monozygotic (MZ)?
identical twins.
share 100% of genetic makeup
develop from one fertilised egg
what is dizygotic (DZ)?
non identical twins
develop from 2 fertilised eggs
share 50% of genetic makeup
what does concordant mean?
the presence of the same trait in both members of a pair of twins
what does discordant mean?
when one twin shows a trait the other doesn’t
strengths of biological approach?
uses scientific methods (EEG etc); technological advancements means it’s not open to bias
quantitative data
real life applications such as development of psychoactive drugs
twin studies have lots of data
explanations in terms of neurotransmitters
limitations of biological approach?
only discovers association between 2 factors, can’t be sure one causes the other
quantitative data
deterministic- sees behaviour as out of our control: implications for legal system
reasons for behaviour can’t be explained
cannot separate nature and nurture in twin/family studies
cannot account for why DZ twins show higher concordance than normal siblings
what is the central nervous system (CNS)?
made up of the brain and spinal cord
the brain ensures life is maintained and is responsible for planning, problem solving, thinking etc
the spinal cord facilitates messages to and from the brain and PNS and is involved in reflex actions
what is a motor neuron?
part of CNS
carry’s information about movement out from the brain
have long axons
carries nerve impulses to muscles
what is a sensory neuron?
part of CNS
carries sensory information inward to the CNS
carries nerve impulses from receptors in the PNS to the CNS
what are the stages of a reflex behaviour?
- sensory information about the heat is detected and passed to the CNS by sensory neurons
- they pass the message on to a relay/interneuron in the spinal cord
- this sends a message down a motor neuron to the muscles, which contract, causing you to move your arm
what is the peripheral nervous system (PNS)?
the nerves that are outside the brain and spinal cord
transmits messages via the millions of neurons to the whole body from the brain and vise versa
broken down into the somatic and autonomic systems
what does the somatic system do?
transmits and recieves messages from the senses
e.g. visual from the eyes
also controls muscle movements and receives information from sensory receptors
what does the autonomic system do?
transmits and receives messages from the organs
governs vital functions like breathing, digestion, heart rate and stress responses (automatic processes)
broken down into the parasympathetic and the sympathetic systems
what is the parasympathetic system?
Constricts pupils Stimulates tear glands Strong stimulation of salivary flow inhibits heart, dilates arterioles Constricts bronchi Stimulates stomach motility and secretion stimulates pancreas Stimulates intestinal motility Contracts bladder Stimulates erection
what is the sympathetic system?
prepares the body for action
Dilates pupils No effect on tear glands Weak stimulation of salivary flow Accelerates heart, constricts arterioles Dilates bronchi Inbibits stomach motility and secretion inhibits pancreas and adrenals. Inhibits intestinal motility Relaxes bladder Stimulates ejaculation
what is the axon?
takes information away from the cell body
what is the axon terminals?
hair like ends of the axon
what is the cell body (soma)?
contains the nucleus