Synaptic Transmission

> synapse: spaces between neurons, or between neurons and effectors

> vesicles containing chemical neurotransmitters are located at the end of neuron axons

Electrical Signals:

> electrical impulses moving along the axon stimulate the release of neurotransmitters

Chemical Signals:

> neurotransmitters are released from the presynaptic neuron and diffuse across the synaptic cleft

> neurotransmitters reaching the postsynaptic neuron depolarize it’s dendrites

Acetyolcholine and Cholinesterase:

Acetylcholine

> is an excitatory neurotransmitter -> causes depolarization on the postsynaptic neuron by opening Na+ ion channels

Cholinesterase

> destroys acetylcholine free floating and bound to receptors in a synapse

> causes Na+ ion channels to close and repolarization to occur -> neuron can be depolarized again

> not all neurotransmitters may be excitatory, some may be inhibitory -> preventing depolarization

> inhibitory neurotransmitters open more K+ gates, making the inside of the neuron even more negative; hyperpolarized

Summation

> the effect produced by the accumulation of neurotransmitters from two or more neurons

Excitatory and Inhibitory Neurotransmitters:

> both are used by your body to coordinate complex bodily functions

Example: throwing a ball

> excitatory neurotransmitters contract your triceps and inhibitory neurotransmitters relax your bicep, this prevents both muscles from pull against each another

Example: listening to a biology lecture

> excitatory neurotransmitters focus the lecture skills (listening, writing, eye movement, etc)

> inhibitory neurotransmitters suppress non essential information (temperature, pressure from clothes, etc)

> both types of neurotransmitters allow your CNS to prioritize information