Ch. 17 definitions

Amygdala

An almond shaped structure in the limbic system, Responsible for feelings of fear, avoidance, and anger

Action potential

A rapid change in polarity across the membrane of an axon as a nerve impulse occurs

Broca’s area

A part of the brain, that’s crucial for the ability to speak

Central canal

Innermost part of the spinal cord containing cerebrospinal fluid

Axon

The part of a neuron that conducts nerve impulses away from the cell body and towards other neurons

Dendrites

The part of a neuron that receives signals from other neurons and sends them to the cell body

The cell body

Contains the nucleus and other organelles

The cerebellum

Maintains posture and balance, and ensures that muscles work together to produce smooth coordinated voluntary movements (Located at the back bottom part of the brain)

The cerebrum

The largest portion of the brain separated into two hemispheres (left and right) It communicates and coordinates the activities of the other parts of the brain

Corpus callosum

An extensive bridge of nerve tracks separating the left and right cerebral hemispheres

ganglion

Swelling’s associated with nerves that contain collections of cell bodies

The hippocampus

A seahorse shaped structure in the lymbic system responsible learning and memory

Hypothalamus

A center in the diencephalon that helps maintain homeostasis and Controls the pituitary gland

The Thalamus

Receives all sensory input (except for smell) to send to the cerebrum. Located in the Diencephalon

Interneuron

Lie entirely in the central nervous system and receive input from sensory neurons and other interneurons to later communicate with motor neurons

Motor neurons

Take messages away from the central nervous system to an effector

Sensory neurons

Take messages away from the central nervous system, Their receptors detect changes in the environment

Neuron

A cell that transmits nerve impulses between parts of the nervous system

Medulla oblongata

A part of the brain stem that regulates vital functions and reflexes (coughing, sneezing)

Pons

Contains bundles of axons travelling between The cerebellum and the rest of central nervous system. It works with the medulla oblongata

Midbrain

A critical part of the brain stem responsible for Visual and audio responses

Myelin sheath

A protective layer around some axons formed when Schwann cells wrap themselves around an axon

Synaptic cleft

A tiny gap That separates to neurons from physically touching

Synapse

The region of close proximity between