biopsychology lessons 1-5 Flashcards
THE NERVOUS SYSTEM DIAGRAM
nervous system
central nervous system. peripheral nervous system
brain. spinal cord. somatic nervous system. autonomic nervous system
sympathetic nervous system parasympathetic NS
what is CNS
made up of brain and spinal cord. brain split into two hemispheres. spinal cord is extension of brain responsible for reflex actions also connects nerves to PNS
what is PNS
transmits messages to and from the CNS. divided into autonomic and somatic.
ANS - vital unconscious functions such as breathing and heart rate
SNS - controls conscious functions such as muscle movement
what are the brain components
cerebrum - split into 4 lobes - frontal, temporal, parietal, occipital. two hemispheres which communicate via corpus callosum
cerebellum - back of cerebrum which controls skills and balance
diencephalon - sits above brain stem and split into 4 - thalamus, hypothalamus, epithalamus, subthalamus. coordinates endocrine system.
brain stem - regulates automatic functions such as breathing and heart rate
what is the somatic nervous system
facilitates communication between the CNS and the outside world through muscle movement
what is the autonomic nervous system
regulates involuntary actions such as heart beats and digesting food. ANS control centre is in the brain stem
what is the sympathetic nervous system
involved in responses that help us deal with fight and flight such as increasing heart rate etc.
what is the parasympathetic nervous system
relaxes body after an emergency has passed by slowing the heart beat and is involved in energy conservation
what are structure of neurone components
cell body: contains nucleus and has dendrites attached
axon: has myelin sheath to speed electrical transmission which are segmented by nodes of ranvier
axon terminal: at end of axon which communicates with next neurone
what are the 3 types of neurones
sensory: carry messages from PNS to CNS. has nucleus on axon
relay: connect sensory to motor. has short dendrites and no myelin sheath
motor: connects CNS to effectors has short dendrites and myelin sheath
what is synaptic transmission
process by which neighbouring neurones communicate with each other by sending chemical messages
describe the process of synaptic transmission
when a neurone is activated by a stimulus the inside becomes positively charged causing an action potential to occur which creates an electrical impulse which travels down axon. once action potential reaches axon terminal it crosses gap between pre-synaptic neurone and post synaptic neurone which is the synapse. axon terminal has synaptic vessels which contain neurotransmitters.
what are inhibitory neurotransmitters
responsible for calming the mind and body. eg. serotonin and GABA. inhibitory neurotransmitter binding to post synaptic cell results in an inhibitory post synaptic potential making neurone less likely to fire.
what are excitatory neurotransmitters
likely to increase your chances to activate or carry out a behaviour. eg. adrenaline and dopamine. when excitatory neurotransmitter binds to post synaptic receptor it causes electrical charge on membrane of post synaptic neurone resulting in excitatory post synaptic potential meaning post synaptic cell is more likely to fire
what is summation
the net result of adding up the excitatory and inhibitory synaptic input
how can the strength of EPSP’s be increased
by spatial summation whereby a large number of EPSP’s are generated at many different synapses.
by temporal summation whereby a large number of EPSP’s are generated at the same synapse by a series of high frequency action potentials.
what is the role of the endocrine system
network of glands and hormones which control vital functions. slower but more long lasting changes than the nervous system.
pituitary gland function
master gland which controls the release of hormones from other glands
hypothalamus role
stimulates and controls release of hormones from pituitary gland.
thyroid role
releases thyroxine which regulates metabolic rate
adrenal medulla role
releases adrenaline which induces a fight or flight response
adrenal cortex role
releases glucocorticoids such as cortisol which release stored glucose and suppresses immune system
releases mineralocorticoids which regulate water balance
testes role
releases androgens mainly testosterone which develops male sexual characteristics and promotes muscle mass.
ovaries role
releases oestrogens mainly oestradiol which regulates female reproductive system and menstrual cycle.