Lecture on the Nervous System and Neuronal Structure

A collection of flashcards covering key concepts related to the autonomic nervous system, neuronal structure, and related histology.

Sympathetic Nervous System

Associated with the fight or flight response, increasing heart rate and dilating pupils.

Parasympathetic Nervous System

Associated with rest and digest, reducing heart rate and promoting digestion.

Enteric Plexus

A network of neurons within the digestive system, containing as many neurons as the brain.

Central Nervous System (CNS)

Composed of the brain and spinal cord, responsible for processing information.

Action Potential

An electrical impulse that travels down the axon of a neuron.

Neuroglia (Glial Cells)

Supporting cells of the nervous system that maintain homeostasis, form myelin, and provide support and protection for neurons.

Dendrites

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

Axon

A long projection of a neuron that transmits electrical impulses away from the soma to other neurons or effectors.

Myelin Sheath

A protective insulating covering around the axon that increases the speed of impulse transmission.

Saltatory Conduction

The process by which nerve impulses jump from one node of Ranvier to another along the axon, speeding up transmission.

Schwann Cells

Cells in the peripheral nervous system that wrap around axons to form myelin sheath.

Oligodendrocytes

Cells in the central nervous system that form myelin sheath around multiple axons.

Astrocytes

Star-shaped glial cells in the CNS that support neurons, regulate blood flow, and form the blood-brain barrier.

Microglia

Small glial cells in the CNS that act as immune defenders, cleaning up debris and pathogens.

Ependymal Cells

Ciliated cells lining the ventricles of the brain that produce cerebrospinal fluid.

Soma (Cell Body)

The central part of a neuron that contains the nucleus and organelles.

Internal Urethral Sphincter

Muscle controlling the release of urine from the bladder; under involuntary control.

External Urethral Sphincter

Skeletal muscle controlling the release of urine; under voluntary control.

Neurons

Excitable cells that transmit electrical signals in the nervous system.

Multipolar Neuron

A neuron with one axon and multiple dendrites, most common type in the CNS.

Bipolar Neuron

A neuron with two distinct processes: one axon and one dendrite, found in special senses.

Pseudo Unipolar Neuron

A sensory neuron with one process that splits into two, found in dorsal root ganglia.

Synapse

The junction between two neurons where neurotransmitters are released.

Axodendritic Synapse

A synapse in which the axon of one neuron connects to the dendrite of another.

Axosomatic Synapse

A synapse where the axon of one neuron connects to the soma of another.

Gray Matter

Regions of the CNS primarily composed of neuronal cell bodies.

White Matter

Regions of the CNS primarily composed of myelinated axons.

Nerve

A bundle of axons in the peripheral nervous system.

Tract

A bundle of axons in the central nervous system.