Nervous System Overview

These flashcards cover essential vocabulary related to the structure and function of the nervous system.

Central Nervous System (CNS)

Consists of the brain and spinal cord; serves as the integration and control center of the body.

Peripheral Nervous System (PNS)

Part of the nervous system outside the CNS; consists mainly of nerves that extend from the brain and spinal cord.

Sensory Input

Information gathered by sensory receptors about changes in internal and external environments.

Integration

The processing and interpretation of sensory input by the nervous system.

Motor Output

Activation of effector organs (muscles and glands) to produce a response.

Neuroglia

Small cells that support and protect neurons in the nervous system.

Neurons

Excitable cells that transmit electrical signals throughout the nervous system.

Myelin Sheath

A protective covering around axons, formed by glial cells, that increases the speed of nerve impulse transmission.

Astrocytes

Star-shaped glial cells in the CNS that support and brace neurons, control the chemical environment, and influence synaptic transmission.

Oligodendrocytes

Glial cells in the CNS that form myelin sheaths around axons.

Somatic Nervous System

A subdivision of the PNS that controls voluntary movements by activating skeletal muscles.

Autonomic Nervous System

A subdivision of the PNS that regulates involuntary control over smooth muscle, cardiac muscle, and glands.

Dendrites

Branch-like structures of neurons that receive signals from other neurons.

Axon

A long projection of a neuron that transmits impulses away from the cell body.

White Matter

Regions of the brain and spinal cord containing myelinated nerve fibers.

Gray Matter

Regions of the brain and spinal cord composed mainly of neuron cell bodies and unmyelinated fibers.

Cerebrospinal Fluid (CSF)

Fluid that cushions the CNS, nourishes the brain, and removes waste.

Blood-Brain Barrier

A selective barrier that protects the brain from harmful substances in the bloodstream.

Reflex Arc

The neural pathway that controls a reflex action, involving a receptor, sensory neuron, integration center, motor neuron, and effector.