Peripheral Nervous System

What are the two main divisions of the nervous system?

The Peripheral Nervous System (PNS) and the Central Nervous System (CNS).

What structures are included in the Central Nervous System (CNS)?

The brain and spinal cord.

What structures are included in the Peripheral Nervous System (PNS)?

Nerves (cranial and spinal) and ganglia.

How many pairs of cranial nerves are there?

12 pairs.

How many pairs of spinal nerves are there?

31 pairs.

What is the function of sensory neurons?

To carry signals to the brain.

What is the function of motor neurons?

To carry signals from the brain to the body.

What is the role of interneurons in the nervous system?

To bridge sensory and motor signals in the CNS.

What is a reflex arc?

An involuntary response to a dangerous stimulus.

What are the steps of a reflex arc?

1. Stimulus, 2. Sensory signal travels to spinal cord, 3. Interneuron is activated, 4. Motor impulse is created, 5. Muscle fires/moves.

What are dermatomes?

Divisions of sensory regions in the body.

What are the two divisions of the Autonomic Nervous System?

Sympathetic (fight or flight) and Parasympathetic (rest and digest).

What is the function of the sympathetic nervous system?

To prepare the body for 'fight or flight' responses.

What is the function of the parasympathetic nervous system?

To promote 'rest and digest' activities.

What are the main parts of a neuron?

Dendrites, cell body (soma), axon, and myelin sheath.

What is the role of the myelin sheath?

To insulate the axon and speed up signal transmission.

What is a synapse?

The junction where signals are passed from the axon terminal of one neuron to the dendrites of another.

What is gray matter?

Unmyelinated nerve fibers and cell bodies.

What is white matter?

Myelinated nerve fibers that facilitate communication across different parts of the nervous system.

What are the functions of the frontal lobe?

Decision making, smell, speech filter/creation, and higher-level thinking.

What are the functions of the parietal lobe?

Spatial awareness and touch interpretation.

What are the functions of the temporal lobe?

Hearing and short-term memory.

What are the functions of the occipital lobe?

Vision.

What is the longest nerve in the body?

The sciatic nerve.

What is the purpose of the Homunculus?

To show how certain areas of the body are more sensitive than others.

What is the role of the olfactory nerve?

To provide the sense of smell.

What is the role of the optic nerve?

To provide the sense of vision.