parts of the nervous system chapter 12

Overview of the Nervous System

Includes parts such as Brain, Central Nervous System, Cranial Nerves, Glands, Muscles, Nerves, Peripheral Nervous System, Sensory Receptors, Spinal Cord, and Spinal Nerves.

Neurons

Cells in the nervous system that transmit impulses; consists of Axon, Nerve Cell Body, and Dendrites.

Dendrites

Parts of a neuron that receive impulses.

Axon

The part of a neuron that creates nerve impulses.

Myelin

Fatty insulation for neurons that enhances the speed of impulse transmission.

Neurotransmitters

Chemical messengers carrying signals for electrical impulses between neurons.

Grey Matter

Regions of the CNS composed of unmyelinated cells and dendrites.

White Matter

Regions of the CNS composed of myelinated nerve fibers, appearing white.

Meninges

Three protective connective tissue layers surrounding the brain and spinal cord: Dura Mater, Arachnoid Layer, Pia Mater.

Cerebrum

Largest part of the brain; responsible for higher functions such as thought and action.

Frontal Lobe

Part of the brain responsible for motor function, personality, and speech.

Afferent Neurons

Also known as sensory neurons; carry sensory information from receptors to the brain.

Efferent Neurons

Also known as motor neurons; send signals from the brain to the rest of the body.

Autonomic Nervous System

Part of the peripheral nervous system that controls involuntary actions; includes sympathetic and parasympathetic branches.

Sympathetic Branch

Part of the autonomic nervous system that controls the fight or flight response.

Parasympathetic Branch

Part of the autonomic nervous system that controls rest and digest functions.

Somatic Nerves

Nerves that serve the skin and skeletal muscles, controlling voluntary movements.

Ganglion

A collection of nerve cell bodies in the peripheral nervous system.

Spinal Cord

Pathway for impulses to and from the brain, composed of 33 vertebrae.

Synapse

Junction between dendrites of one neuron and another neuron; where electrical impulses do not pass.

Central Nervous System (CNS)

Composed of the brain and spinal cord, integrates and processes information.

Thalamus

Grey matter in the brain that processes special senses.

Hypothalamus

Region of the brain that manages sleep, emotions, body temperature, appetite, and autonomic functions.