biopsychology content Flashcards
name the components of the nervous system
divides into central nervous system (CNS) and peripheral nervous system (PNS).
CNS divides into brain and spinal cord
PNS divides into autonomic nervous system (ANS) and somatic nervous system (SNS).
ANS divides into the sympathetic and parasympathetic nervous systems.
describe the role of the somatic nervous system
consists of sensory and motor neurones to carry senseroy and motor information to and from the CNS.
enables reflex actions.
what are the roles of the sympathetic and parasympathetic nervous systems?
sympathetic - involved in fight/ flight
parasympathetic -involved in ‘rest and digest’ functions
name the parts of a typical neurone
- dendrites
- cell body
- nucleus
- axon
- myelinated sheath
- nodes of ranvier
- axon terminal
describe the structure and function of a neuron
- neurones enable communication within the nervous system.
- The cell body (soma) contains the genetic material (in nucleus)
- branch like dendrites extend from the cell body
- dendrites carry functional information towards the cell body
- dendrites can receive info from other neurones
- axons carry messages away from the cell body
- axons can be myelinated to increase speed of nerve transmission
- nodes of ranvier allow for saltatory conduction
- terminal boutons are at the end of axons and make the synaptic connections with other cells
- axon terminal contain neurotransmitters.
describe the divisions of the nervous system
- the nervous system is divided into the central and peripheral nervous systems
- the CNS comprises of the brain and spinal cord
- The PNS divides into the somatic nervous system and autonomic nervous system.
- somatic nervous system consists of sensory and motor neurones to carry sensory and motor information to and from the CNS and enables reflex actions
- the ANS acts involuntarily
- ANS divides into the sympathetic and parasympathetic nervous systems.
- sympathetic nervous system involved in fight or flight response
- parasympathetic nervous system involved in ‘rest and digest’ functions.
what is the function of the sensory neurone?
receives information from the receptors (e.g. skin) and sends the info towards the relay neurone in the brain
from receptors to brain
what is the function of the relay neurone?
takes information from the sensory neurone and passes it around the brain, towards the appropriate motor neurons
in the brain
what is the function of the motor neurones?
receives info from the relay neurones and passes down to the effectors to make muscle movements e.g. dropping a pan.
from brain to muscles
which neurone goes towards the brain?
sensory
which neurone goes away from the brain?
motor
which neurone is in the CNS?
relay
outline synaptic transmission
- an action potential comes down from the axon
- stimulates calcium ions and the production of vesicles which contains neurotransmitters.
- the vesicles release neurotransmitters which diffuse across synaptic gap from an area of high conc to low.
- neurotransmitters bind to complementary receptors in post synaptic membrane, allowing sodium ions to move into post synapse
- this creates an action potential in the post synapse
- neurotransmitters are released and taken back into presynapse through a reuptake process and enzymes break down any remaining neurotransmitters in presynapse and synaptic gap
Zapurpain acts like an inhibitory transmitter at the synapse.
explain how Zurpurpain might affect the process of synaptic transmission through inhibition
Zapurpain mimics the effects of inhibitory neurotransmitters, stimulation of postsynaptic receptors by an inhibitory neurotransmitter result in inhibition (hyperpolarisation) of the post synaptic membrane.
when an inhibitory neurotransmitter binds to postsynaptic receptors, it makes the post synaptic cell less likely to fire (IPSP)
summation- if inhibitory inputs are higher than excitatory they can cancel out excitation and inhibit an action potential occurring (Zapurpain would decrease overall activity)
- Zapurpain would make the post-synaptic cell less likely to fire
what does an inhibitory neurotransmitter (IPSP) do?
- slows down the firing rate on the post synapse as it increases the threshold at which an action potential can be reached at the post synapse (hyperpolarisation)
