Synapses and Neurotransmitters 1-3

Question 1

Compare and contrast the key features, functions, and capabilities of chemical vs. electrical synapses.

Answer 1

Electrical synapses
-Signals pass in both directions
-Signals passed directly
-Good for fast communication and synchronising neurons
-Formed of gap junctions, very small spaces

Chemical synapses
-Signals pass in one direction
-Signals can be transformed
-Slower

Both
-Can be modified, “plastic”
-Allow summing up inputs by postsynaptic neuron

Question 2

Define the criteria that a molecule must meet to be a neurotransmitter.

Answer 2

-Must be present in presynaptic terminals
-Must be released in response to stimulation
-Must act on the postsynaptic neuron
-Blocking the neurotransmitter should prevent synaptic transmission

Question 3

Describe disorders where neurotransmitter systems are impaired, and explain why these neurotransmitter systems are linked to the identified disorders.

Answer 3

Parkinsons
-The nigrostriatal pathway facilitates the initiation of voluntary movement
-These neurons die in parkinsons, leading to motor dysfunction
-Can be treated by increasing dopamine