NEU_LEC_4

Neuron

A nerve cell that receives and transmits information to other neurons or muscles.

Glial cells

Cells that support, nourish, and protect neurons; they outnumber neurons in the nervous system.

Myelin

A lipid covering formed by glial cells that insulates axons and increases the speed of action potentials.

Astrocytes

Star-shaped glial cells that support neurons and regulate blood flow in response to neural activity.

Oligodendrocytes

Glial cells in the CNS that produce myelin for axons.

Microglia

Immune cells in the CNS that clean up debris and damaged neurons.

Dendrites

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

Axon hillock

The part of a neuron that integrates incoming signals and generates action potentials.

Synapse

The junction between the presynaptic and postsynaptic neurons, where neurotransmitters are released.

Sensory Neurons

Neurons that carry information from sensory receptors to the brain.

Motor Neurons

Neurons that carry commands from the brain to muscles or glands.

Interneurons

Neurons that connect sensory neurons and motor neurons; they primarily function within the CNS.

Nodes of Ranvier

Gaps in the myelin sheath along the axon that facilitate rapid conduction of action potentials.

Cranial Nerves

Nerves that arise from the brain; there are 12 pairs, each serving different sensory and motor functions.

Peripheral Nervous System (PNS)

Part of the nervous system outside the CNS that includes sensory and motor nerves.

Central Nervous System (CNS)

The part of the nervous system that includes the brain and spinal cord.

Action Potential

An electrical signal that travels down the axon and triggers the release of neurotransmitters.

Autonomic Nervous System

Part of the PNS that controls involuntary bodily functions.

Sympathetic Nervous System

Part of the autonomic nervous system that prepares the body for 'fight or flight' responses.

Parasympathetic Nervous System

Part of the autonomic nervous system that conserves energy and promotes 'rest and digest' functions.

Lamina

A row or layer of cell bodies in the nervous system, separated by layers of axons and dendrites.

Tract

A set of axons within the CNS that project from one region to another.

Nucleus (neuroscience)

A cluster of neuronal cell bodies within the CNS.

Ganglion

A cluster of neuronal cell bodies found in the PNS.

Gyrus

A protuberance on the surface of the brain.

Sulcus

A fold or groove separating gyri in the brain.

Fissure

A long, deep sulcus in the brain.