Cells of the nervous system - neurons and glia

A set of flashcards covering key terms and definitions related to the structure and function of cells in the nervous system, based on the lecture notes for MEDU3300.

Neuron

A nerve cell that receives stimuli and transmits action potentials.

Glia

Support and protect neurons; produce myelin sheath for insulation.

Astrocyte

Glial cell type that maintains blood-brain barrier and supports neuronal function.

Oligodendrocyte

Glial cell type in the CNS that generates and maintains myelin sheath.

Ependymal cells

Glial cells that line brain ventricles and spinal cord central canals.

Microglia

Immune cells of the CNS that act as macrophages and respond to injury.

Schwann cells

Glial cells in the PNS that form myelin sheath around axons.

Node of Ranvier

Gaps in the myelin sheath that facilitate saltatory conduction.

Saltatory conduction

The jumping of action potentials between nodes of Ranvier.

Neuron doctrine

The concept that neurons are distinct anatomical and functional units.

Dendrites

Branching extensions that receive signals from other neurons.

Axon

A single, long extension that transmits action potentials to other cells.

Soma (cell body)

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

Synapse

The junction between two neurons where signals are transmitted.

Neuromuscular junction

The synapse between a motor neuron and a skeletal muscle fiber.

Excitability

The ability of a neuron to respond to stimuli and generate action potentials.

Conductivity

The ability of neurons to transmit electrical signals over distances.

Secretion

The process by which neurons release neurotransmitters at synapses.

Chromatolysis

The breakdown of Nissl bodies after axonal injury.

Nissl bodies

Rough endoplasmic reticulum in neurons involved in protein synthesis.

Afferent neurons

Neurons that carry signals toward the central nervous system.

Efferent neurons

Neurons that carry signals away from the central nervous system.

Interneurons

Neurons that connect other neurons within the CNS.

CNS

Central Nervous System, comprising the brain and spinal cord.

PNS

Peripheral Nervous System, composed of all nerve tissues outside the CNS.

Myelin sheath

An insulating layer around axons that enhances signal transmission speed.

Axon hillock

The conical part of a neuron where action potentials are initiated.

Neurotransmitter

Chemical substances that transmit signals across a synapse.

Acetylcholine

A neurotransmitter involved in muscle activation at the neuromuscular junction.

Myasthenia Gravis

An autoimmune disease affecting synaptic transmission at the neuromuscular junction.

Blood-brain barrier

A selective permeability barrier that protects the brain from harmful substances.

Gliosis

The reactive change of glial cells in response to CNS injury.

Neurotrophins

Proteins that support neuron growth and survival.

Regeneration

The process of neural repair following injury.

Inflammation

The body's response to injury which can sensitize neurons.

Chronic pain

Pain that persists after the initial injury has healed.

Glutamate

An excitatory neurotransmitter involved in synaptic transmission.

Cytokines

Signaling molecules that mediate inflammation in the nervous system.

Peripheral nerve sheath

Connective tissue that surrounds and protects peripheral nerves.

Action potential

An electrical signal that travels along the axon of a neuron.

Synaptic cleft

The space between the presynaptic and postsynaptic neurons.

Motor end plate

The specialized postsynaptic membrane at the neuromuscular junction.

Phagocytosis

The process by which microglia engulf and digest debris.

Neurons

Cells in the nervous system responsible for receiving and sending signals.

Reactive astrocytes

Astrocytes that become active in response to CNS injury.

Axonal transport

The process of transporting materials along axons.

Neuroscience

The study of the nervous system, its structure, functions, and diseases.

Neural hypersensitivity

Increased sensitivity to stimuli following nerve injury.

Phenotype

The observable physical and physiological traits of an organism,

Differentiation

The process by which cells develop specific functions.

Ciliary beating

The coordinated movement of cilia found on ependymal cells.

Cellular transport channels

Proteins that enable movement of substances across cell membranes.