Neuroscience: CNS, PNS, Neurons, Glia, and Blood-Brain Barrier

CNS (Full Name)

Central Nervous System[cite: 2]

PNS (Full Name)

Peripheral Nervous System[cite: 2]

Motor Division (PNS)

The part of the PNS that carries signals from the CNS to muscles or glands[cite: 2]

Sensory Division (PNS)

The part of the PNS that carries signals toward the CNS[cite: 2]

Somatic Nervous System

The division of the motor system that provides voluntary control[cite: 2]

Autonomic Nervous System

The division of the motor system that provides involuntary control[cite: 2]

Dendrites

The parts of a neuron that receive communication from other cells[cite: 2]

Soma

The cell body of a neuron[cite: 2]

Axon Hillock

The initial segment of the axon where the nerve impulse begins[cite: 2]

Axon

The long, slender projection of a neuron that conducts electrical impulses[cite: 2]

Myelin

The insulating layer around an axon that increases signal speed[cite: 2]

Node of Ranvier

Gaps in the myelin sheath along the axon[cite: 2]

Axon Terminal

The end of an axon branch that forms a synapse[cite: 2]

Pre-Synaptic Knob

The distal tip of an axon terminal that releases neurotransmitters[cite: 2]

Neuron Polarity Definition

Refers to the direction of a nerve impulse[cite: 2]

Pseudo-Unipolar Neurons

Neurons that are exclusively sensory in function[cite: 2]

Pseudo-Unipolar Location

Somas are located in the spinal ganglia[cite: 2]

Bipolar Neurons

Neurons found only in the olfactory epithelium and the retina[cite: 2]

Multipolar Neurons

Neurons with one axon and two or more dendrites[cite: 2]

Multipolar Neuron Prevalence

The structure used by nearly all neurons in the body[cite: 2]

Astrocytes (CNS)

Glial cells that support neurons and maintain their surrounding environment[cite: 2]

Oligodendrocytes (CNS)

Glial cells that produce myelin sheaths in the central nervous system[cite: 2]

Microglia (CNS)

Glial cells responsible for immune surveillance and acting as resident macrophages[cite: 2]

Ependymal Cells (CNS)

Glial cells responsible for the production of cerebrospinal fluid (CSF)[cite: 2]

Satellite Cells (PNS)

Glial cells in the PNS that support neurons and maintain their environment[cite: 2]

Schwann Cells (PNS)

Glial cells that produce myelin sheaths in the peripheral nervous system[cite: 2]

Blood-Brain Barrier (BBB)

A highly selective semipermeable barrier between the blood and brain[cite: 2]

BBB Component: Endothelial Cells

Capillary cells joined by tight junctions to form the barrier[cite: 2]

BBB Component: Astrocyte Foot Processes

The "end-feet" of astrocytes that help form the barrier[cite: 2]

BBB Permeability: Simple Diffusion

Molecules like O2, CO2, alcohol, caffeine, and nicotine can cross[cite: 2]

BBB Permeability: Facilitated Transport

Molecules like glucose and amino acids require transport to cross[cite: 2]

BBB Excluded Substances

Toxins, pathogens, white blood cells, and antibodies[cite: 2]