psych neuron pop quiz

What is the main job of the nervous system?

To receive and process information and coordinate the body's responses.

What are the two main parts of the nervous system?

Central nervous system (brain and spinal cord) and peripheral nervous system.

What does the somatic nervous system control?

Voluntary movements of skeletal muscles.

What does the autonomic nervous system control?

Involuntary functions like heartbeat and digestion.

What is the sympathetic nervous system?

The fight-or-flight system; it prepares the body for action.

What is the parasympathetic nervous system?

The rest-and-digest system; it calms the body.

What are the three main parts of a neuron?

Dendrites, cell body (soma), and axon.

What do dendrites and axons do?

Dendrites receive messages; axons carry impulses away from the cell body.

What is the myelin sheath?

A fatty covering around axons that speeds up neural impulses.

What is a neurotransmitter?

A chemical messenger that carries signals between neurons.

What is a synapse?

The tiny gap between neurons where neurotransmitters travel.

What are receptors?

Proteins that neurotransmitters bind to in order to pass along signals.

What is the threshold?

The minimum stimulation needed to trigger a neural impulse.

What is the all-or-nothing principle?

A neuron either fires completely or doesn't fire at all.

What is an action potential?

A brief electrical impulse that travels down the axon.

What is the refractory period?

A brief period after firing when a neuron cannot fire again or is less likely to fire.

What is reuptake?

When the sending neuron reabsorbs neurotransmitters from the synapse.

What is the difference between an agonist and an antagonist?

An agonist increases or mimics a neurotransmitter's effects; an antagonist blocks or reduces them.

How do SSRIs work?

They block serotonin reuptake, leaving more serotonin available in the synapse.