Neuron Signalling

Question 1

Parts of the Synapse

Answer 1

Presynaptic membrane
Postsynaptic membrane
Vesicles
Synpatic cleft
Autoreceptors
Receptors

Question 2

Seven Processes in NT Action

Answer 2

1. Synthesized from precursors
2. Stored in Vesicles
3. Leaked NT are broken down by enzymes
4. AP trigger release into synaptic cleft
5. Bind with autoreceptors
6. Diffuse across cleft and bind with receptors
7. Deactivated

Question 3

Properties of a NT

Answer 3

Produced and stored in neuron
Released into synaptic cleft
Deactivated down by enzymes
Able to bind to receptors

Question 4

Ionotropic Receptor

Answer 4

Contains binding site for NT and ion channel

Channel opens when bound to allowing influx of ions to cross membrane into cell

Question 5

Metabotropic Receptor

Answer 5

Contains binding site for NT which activates a secondary messenger (enzyme) that begins a series of events, eventually opening ion channels somewhere else on the membrane

Question 6

Neurotransmitter vs. Hormones

Answer 6

Neurotransmitter:
Signals short distance
Precise and direct location
Rapid messaging - milliseconds
Can be voluntary
All-or-none

Hormones:
Signals long distances
Released into bloodstream and picked up anywhere w/ receptor
Slower messaging - seconds/minutes
Involuntary
Continuously variable

Question 7

Six steps of Hormonal Signalling

Answer 7

1. Synthesized in Endocrine glands
2. Stored and secreted from glands
3. Transported to target cells via bloodstream
4. Bind to receptors
5. Signal relayed and amplified by target cells
6. Breakdown of hormone