Chemical And Electrical Synapses Flashcards
What are some characteristics of electrical synapses
Neuronal to non-neuronal transmission
3nm gap (smaller then that of the chemical synapses)
Direct transfer of ion current
Connexion pores that connect the gap junctions
Cardiac and uterine muscle
Brain development
What are characteristics of chemical synapses
Receptors of pre and post synapses
20-50nm gap (larger then the electrical synapses at 3nm)
Vesicles containing the neurotransmitter
What are some amino acid transmitters
GABA
Glutamate
Glycine
What are some amine transmitters
Noradrenaline
Dopamine
Histamine
What are some peptide transmitters
Substance p
Neuropeptide y
What are the difference between the AA/amine and the peptide transmitters
AA/Amine would be in the vesicles that would released at the axon terminal
Peptide would move in secretory granules from the axon to the terminal in axoplasmic transport
What is a QUANTA
The lowest amount of neurotransmitter realised from the vesicles
What is temporal and spatial summation
Temporal: Acton potentials coming from the same neurone over time
Spatial: action potentials coming from different neurones all at once
What is presynaptic modulation
A way to stop transmission
Alpha 2 receptor on the pre synaptic binds to noradrenaline
Hyper polarisation (opening of the k+ or closing of the ca++)
Would have no ca++ influx
How would you stop the effect of neurotransmitters and why would you need to do this?
-reuptake
-enzyme degradation
-diffusion
So would not have desensitisation (where the receptors would not longer recognise the transmitters)
What is axodendritic
Axon terminal connecting to the dendrite of another neurones
What is axosomatic
Axon terminal connecting to the soma (cell body) of another neurone
What is axoaxonic
Axon terminal connecting to the axon of another neurone
What do the GABA neurotransmitters do and what do they make the channels permeable to
Inhibitory receptors of the brain
Permeable to CL- so would cause hyperpolerisation
What do the glutamate neurotransmitters do and what do they make channels permeable to
Stimulatory of the brain
Permeable to na+ so leads to depolarisation
What do the glycine transmitters do
Inhibitory of the action potential in the spinal cords
What is the difference between convergence and divergence
Convergence is many neurones to one neurone
Divergence is one neurone to many neurones
What is the difference between symmetrical and asymmetrical synapses
Symmetrical would be the same size (inhibitory)
Asymmetrical would be different sizes (stimulatory)
What is Carpal tunnel syndrome
The median nerve that would run down the forearm and to the metacarpal would be twisted
What is motor neurones disease
Degradation of the Motor neurones in the body
What is cubital syndrome
The ulna nerve in the neurones would be twisted
What is the difference between the heteroreceptors and the auto receptors
Heteroreceptors can use different neurotransmitters then ones that would have been released at the terminal
Auto receptors would use the same neurotransmitters that would be released at the terminal
What are the subunits of the nicotinic receptors
2 alpha (the ach would bind to them)
1 beta
1gamma and 1 delta
Total of 5 units
