Synaptic Transmission Flashcards
Explain why neurons Kelly transmit information in One Direction at a synapse
The synaptic vesicles containing the neurotransmitters are only released from the presynaptic membrane.
The receptors from the neurotransmitters are only present on the postsynaptic membrane
Diffusion of the neurotransmitters mean they can only go from a high to low concentration so can only travel from the presynaptic to the postsynaptic membrane
Explain the process of the synaptic transmission
Electrical impulses reach the presynaptic terminal
electrical impulses to the release of Neurontransmitters
Neuron transmitters cross the synapse from vesicles
Neurotransmitters combined with receptors on the postsynaptic membrane
breifly outline how exitation and inhibitation are invloved in synaptic transmission
neuontransmitters can be excitatory or inhibitory
if NT are EXI then the post synaptic neuron are more lilely to fire and impulse if its an INH then the posy synaptic neurons are less likely to fire an impulse.
EXI and INH are summed
what is relay neuron
they are found between sensory input and motor ouput response. they are found is the brain and spinla cord and allows sensory and motor neurons to communicate.
what is a motor neuron
they are found in the cns and controls muscle movements . when motor neurons are stimulated they release neuronstransmitters that bind to the recptors on mucles to trigger a response
what is a sensory
found in receptors such as the eye and carry nerve impulses to the spinal cors and brain . when nerve impulses reach the brain , they are translated into sensations such as vision
hearing taste and touch . not all neurons reach the brain some stop as spinal cord which allows qucik reflexes
electric transmission
When a neuron is resting, the inside of the cell is negatively charged compared to the outside
- The neuron is activated by a stimulus
- The inside of the cell becomes positively charged
- This causes action potential to occur
- This creates an electrical impulse which travels down the axon
synaptic transmission
Nerve impulse travels down an axon (electrical transmission).
- Nerve impulse reaches the presynaptic nerve terminal.
- Electrical impulse triggers the release of neurotransmitters from tiny sacs called synaptic vesicles.
- The neurotransmitters are fired into the synaptic gap where they diffuse across the synapse.
- Neurotransmitter binds with receptors on the dendrite of the adjacent neuron.
- If successful the neurotransmitter is taken up by the post-synaptic neuron.
jermemy was digging hit rock stopped digging all of a sudden
sensory N sends infor from senses to the brain. receptos in jem hands would sense the jolt and sends infor via periphernal NS
Relay N connect with other N they anyalse the sensations deciding how to respond to it, . acting between the sensory and motor N
moror neurons send messages via long axons from the brain to the muscles making movement stop.
outline the structure and processes involved in synaptic transmission6 marker
The synaptic cleft; pre and postsynaptic membranes; postsynaptic receptor sites, neurotransmitters in vesicles in the presynaptic terminal, release of neurotransmitters into the synaptic cleft when stimulated by nerve impulses (action potentials) arriving at the presynaptic terminal, combination of neurotransmitters with postsynaptic receptors; postsynaptic effects either excitatory (depolarisation) or inhibitory (hyperpolarisation).
breif summary of synaptic transmission
3 marker
Transmission involves impulses crossing a space or gap between an axon terminus and the adjacent neuron (the synapse/synaptic cleft)
- Neurotransmitters are chemicals released from vesicles on the presynaptic neuron
- They travel/diffuse across the synapse and lock onto receptor sites on receiving/postsynaptic neuron
- Some neurotransmitters increase the rate of firing in the receiving neurons and others decrease the rate of firing
- Psychoactive drugs work by affecting (increasing or inhibiting) the transmission of neurotransmitters across the synapse
synaptic transmission 2 marker
Up to 2 marks for an outline of synaptic transmission. One mark for reference to the release of neurotransmitter into the synapse. One mark for reference to neurotransmitter binding with receptors on the dendrite or next neuron to binding another impulse. Credit a diagram that illustrates the process above.
