AS biopsychology Flashcards
what are the two parts of the nervous system
central nervous system
peripheral nervous system
what are the two parts of the central nervous system
brain
spinal cord
what are the two parts of the peripheral nervous system
somatic nervous system
autonomic nervous system
what are the two parts of the autonomic nervous system
sympathetic nervous system
parasympathetic. nervous system
what are the two main functions of the nervous system
collect, process and respond to information in the environment
coordinate the working of different organs and cells in the body
what does the connection between the brain and spinal cord allow for
messages to be sent from brain to body for the body to respond
what is the spinal cord responsible for
reflex actions
what does the SNS do
controls muscle movement and receives information from sensory receptors
what does the ANS do
Governs vital functions in the body such as breathing, digestion, stress responses etc
what does the sympathetic nervous system do
controls ‘fight or flight’ phenomenon, kicks in instantly preparing for fight or escape
what does the parasympathetic nervous system do
slow acting response, tries to reverse the effects of fight or flight response after the scare
what does the endocrine system do
work with nervous system tomaintain homeostasis
how does the endocrine system work
the PNS collects info regarding state of the body
if anything abnormal picked up it is sent to the CNS to make a decision
a signal is then sent to major endocrine glands to secrete the right hormones to maintain homeostasis
what is the master gland
pituitary gland
what does the thyroid gland do
produces thyroxine which effects metabolic rates and in turn affects growth rates
what does the pituitary gland do
controls release of hormones from all other glands- affects growth and many other things
what do the ovaries do
secrete oestrogen and progesterone which control the development of female sex characteristics, puberty and the menstrual cycle
what do the testes do
secrete testosterone- aids development of testes and penis, regulates libido
what does the pancreas do
secretes insulin and glucagon- allows body to use sugar from food for energy, regulates blood sugar levels
what is stress
a physical and psychological response when a person feels like they cannot cope with a stressor
what systems does the stress response use
endocrine and nervous
how is the stress response ‘adaptive’
aids survival
how does the sympathetic nervous system prepare your body for fight or flight
sets down body actions that aren’t essential for fight or flight (digestion etc) and enhances functions necessary (heart rate etc)
what happens when stress subsides
the PNS restores body to resting levels, this is slow-acting and may take several minutes
how does the sympathetic nervous system effect stomach/gut during FFF
slows digestion
how does the sympathetic nervous system effect saliva glands during FFF
inhibits saliva production
how does the sympathetic nervous system effect heart during FFF
increases heart rate
how does the sympathetic nervous system effect bladder during FFF
inhibits urination
how does the sympathetic nervous system effect eyes during FFF
dilates pupils
how does the sympathetic nervous system effect lungs during FFF
dilates bronchi
what deals with acute stress
sympathetic adrenal medullary system
how does the fight or flight mechanism work
hypothalamus triggers activity in the sympathetic branch of the autonomic nervous system
ANS changes from resting parasympathetic state to the physiologically aroused sympathetic state
adrenaline is produced by adrenal medulla in the bloodstream
adrenaline causes physiological changes in target organs in the body and causes increased HR, dilated pupils etc- this is fight or flight
once over the PNS returns body to resting state
where are motor neurone found
CNS
what is the key function of motor neurons
controlling muscle movements
what are the physical features of motor neurons
short dendrite
long axons
where are sensory neurons found
receptor cells (skin, eyes etc)
what is the key function of sensory neurons
carry nerve impulses to the spinal cord and brain which turn impulses into sensations
what are the physical features of sensory neurons
long dendrites
short axons
where are relay neurons found
in between sensory and motor neurons
what is they function of relay neurons
allow sensory and motor neurons to communicate
what are the physical features of relay neurons
short dendrites
long or short axons
how are signals within neurons transmitted
electrically
how are signals between neurons transmitted across synapses
chemically
where are motor neurons located
cell body may be in CNS but long axons form part of the PNS
where are sensory neurons located
located outside on the CNS and in the PNS in clusters called ganglia
where are relay neurons located
make up 97% of all neurons and are located mainly in the brain and visual system
how do neurons fire
when a neutron is in resting state the inside of the cell is negatively charged compared to the outside
when the neutron is activated by a stimulus the inside becomes positively charged for a second causing an action potential to occur.
this creates an electrical impulse which travels down the axon to the end of the neutron
what do the cell body of neurons do
contain the nucleus
have dendrites coming off it
what do dendrites do
carry nerve impulses from other neurons to the cell body
what does the axon do
carry impulses from the cell body to the end of the neutron
what does the myelin sheath do
protect the axon
speeds up electrical transmission
what do the nodes of Ravanier do
speed up electrical transmission by making impulses jump across them
without them the myelin sheath would slow down transmission
explain synaptic transmission
electrical impulse reaches pre synaptic terminal which triggers neurotransmitters to be released by synaptic vesicles
this neurotransmitter diffuses across the synapse
reaches the post synaptic receptors where it is converted back to an electrical impulse
what is an example of an inhibitory neurotransmitter
serotonin
what is an example of an excitatory neurotransmitter
adrenaline
what do inhibitory neurotransmitters do
makes neurons more negatively charged and less likely to fire
what do excitatory neurotransmitters do
make neurons more positively charged and more likely to fire
what determines if a neutron fires or not after synaptic transmission
summation
why can neurotransmitters only travel one way
synaptic vesicles only present at pre synaptic membrane
post synaptic receptors only present on post synaptic membrane- it is binding to post synaptic receptor which allows neutron to fire
diffusion means neurotransmitters can only go from high to low concentration
