Unit 12: Nervous System

These flashcards cover key terminology and concepts from the nervous system lecture.

Neuron

A nerve cell that receives signals, transfers messages, and stimulates responses.

Dendrites

Parts of a neuron that receive nerve stimuli and start nerve impulses.

Soma (Cell Body)

Contains organelles and is a part of a neuron.

Axon

An extension of a neuron that carries nerve impulses away from the neuron.

Myelin Sheath

Insulates the axon and prevents the loss of nerve impulses.

Action Potential

A change in charges during depolarization, sending messages down the neuron.

Resting Potential

The state of a neuron when it is not firing, with a negative inside and positive outside.

Neurotransmitter

A chemical substance released from vesicles at the axon terminus, triggering a response.

Synapse

The gap between the axon terminus of one neuron and the effector (nerve, gland, or muscle).

Cerebrum

Part of the brain responsible for thought, motor skills, sensory processing, and pain.

Hypothalamus

Brain structure that regulates primal needs such as hunger, thirst, and body temperature.

Cerebellum

Part of the brain responsible for balance and coordination.

Spinal Cord

Structure that communicates signals between the brain and body.

Sensory Neurons

Neurons that carry signals from sensory structures to the brain.

Motor Neurons

Neurons that carry signals from the brain to the muscles.

Reflex Arc

An involuntary protective reaction that reduces response time.

Autonomic Nervous System

Part of the nervous system that controls involuntary actions.

Sympathetic Nervous System

Part of the autonomic nervous system responsible for the 'Fight or Flight' response.

Parasympathetic Nervous System

Part of the autonomic nervous system that manages normal reactions.

Mechanoreceptors

Sensory receptors that respond to physical changes.

Photoreceptors

Sensory receptors that respond to light.

Chemoreceptors

Receptors that detect chemicals, located in the mouth and nose.

Astigmatism

A visual defect caused by irregular curvature of the cornea.

Cataracts

A condition in which the lens of the eye becomes cloudy.