Nervous System: Neural Tissue Practice Flashcards

Vocabulary-style flashcards derived from anatomical lecture notes on the nervous system, covering structural and functional classifications, cell types, and information flow.

Central Nervous System (CNS)

Includes the brain and spinal cord.

Peripheral Nervous System (PNS)

Includes cranial nerves, spinal nerves, and sensory receptors; it communicates between the CNS and peripheral tissues.

Neurons

Specialized cells that transfer and process information in the nervous system.

Neuroglia

Specialized cells (glial cells) that support and protect neurons, acting as the connective tissue of the nervous system.

Soma

The nerve cell body containing the nucleus and most organelles.

Dendrites

Neuronal processes that receive information and are NEVER myelinated.

Axon

A neuronal process that carries information; it may be myelinated.

Axon hillock

The initial segment of an axon.

Synaptic bulb

Also called the terminal button, synaptic knob, or synaptic terminal; it is the end of the axon where information transfer occurs.

Anaxonic neuron

A neuron that lacks cell processes; found in the brain and retina.

Bipolar neuron

A neuron with a single dendrite and a centrally located soma between the axon and dendrite; found in special senses like vision, smell, and hearing.

Pseudounipolar neuron

A neuron with continuous axon-dendrite processes and a soma off to the side; locations include visceral sensory neurons.

Multipolar neuron

A neuron with multiple dendrites and a single axon; the most common type in the CNS and found in somatic motor neurons.

Astrocytes

CNS glial cells that regulate the microenvironment, form the blood-brain barrier, provide structural support, and repair damaged tissue.

Oligodendrocytes

Glial cells that myelinate CNS axons, though not all nerves in the CNS are myelinated.

Microglia

The macrophage of the Central Nervous System (CNS).

Ependymal cells

Glial cells that secrete cerebral spinal fluid (CSF).

Schwann cells

Cells that myelinate peripheral nerve axons; in the PNS, all peripheral nerve axons are myelinated.

Satellite cells

The macrophage of the Peripheral Nervous System (PNS).

Gray matter

Comprised of nerve cell bodies and unmyelinated fibers (including all dendrites and unmyelinated axons).

White matter

Comprised of myelinated axons.

Nucleus

A grouping or collection of nerve cell bodies within the CNS.

Ganglia

A grouping or collection of nerve cell bodies within the PNS.

Neural cortex

Superficial gray matter divided into functional regions.

Columns/Tracts

White matter organization found in the spinal cord or brain.

Ascending pathways

Pathways that carry sensory information toward the CNS.

Descending pathways

Pathways that carry motor commands away from the CNS toward peripheral effectors.

Somatic Motor Neurons

Multipolar neurons that innervate skeletal muscle, usually under conscious control.

Autonomic Motor Neurons

Also called visceral motor neurons; multipolar neurons that innervate cardiac muscle, smooth muscle, and glands.

Sympathetic Division

The division of the autonomic nervous system responsible for the "Fight or Flight" response.

Parasympathetic Division

The division of the autonomic nervous system responsible for the "Rest and Repose" (digest) response.

Chemical Synapse

A connection where neurotransmitters are released from the synaptic bulb and bind to receptors on the postsynaptic membrane.

Electrical Synapse

A connection where cells are connected by gap junctions, allowing nerve impulses to travel from cell to cell.

Afferent

A term meaning "going towards," used for division in the PNS that carries sensory info from receptors to the brain.

Efferent

A term meaning "going away from," used for division in the PNS that carries motor commands from the CNS to effectors.

Somatosensory cortex

Located in the postcentral gyrus of the brain, where general sensory information is processed.

Preganglionic neuron

The first neuron in the autonomic system; its soma is in the CNS and its axon extends to a ganglion.

Postganglionic neuron

The second neuron in the autonomic system; its soma is in the ganglion and its axon extends to effector cells.

Interneurons

Mostly multipolar neurons that connect neurons within the CNS to analyze sensory inputs and coordinate motor outputs.