Untitled Flashcards Set

Central Nervous System (CNS)

Core control – brain and spinal cord.

Peripheral Nervous System (PNS)

Peripheral pathways – connects CNS to the body.

Sensory Neuron

Carries info to CNS, senses signals.

Motor Neuron

Sends commands to muscles and glands.

Interneuron

Bridges sensory and motor neurons, an internal link.

Neuron

Basic nerve cell, the neural unit.

Cell Body (Soma)

Support hub that holds the nucleus.

Dendrite

Data branches that receive signals.

Axon

Action line that sends signals away.

Myelin Sheath

Speed layer that speeds up signal transmission.

Node of Ranvier

Gaps in myelin for faster conduction, where signals jump.

Axon Terminal (End Buttons)

Signal stop that releases neurotransmitters.

Synapse

Signal space where neurons connect.

Presynaptic Membrane

Pre-release area that sends neurotransmitters.

Postsynaptic Membrane

Post-receive area that receives neurotransmitters.

Synaptic Vesicle

Signal pack that stores neurotransmitters.

Neurotransmitter

Chemical signal carrier, the neural messenger.

Reuptake

Recycle process that reabsorbs neurotransmitters.

Enzymatic Deactivation

Chemical cleanup that breaks down neurotransmitters.

Resting Potential

Neuron at rest, ready to fire.

Action Potential

Signal spike, an electrical impulse.

Depolarization

Signal activation phase, less negative.

Hyperpolarization

Inhibits firing, more negative.

Threshold of Excitation

Voltage needed to fire, trigger point.

All-or-None Law

Fires completely or not at all, full send or none.

Astrocyte

Star helper that provides nutrients and cleans debris.

Oligodendrocyte

Many myelin maker that creates myelin for CNS axons.

Schwann Cell

Single wrapper that creates myelin for PNS axons.

Microglia

Tiny cleaners that remove waste and fight invaders.

Sodium-Potassium Pump

Ion balancer that maintains neuron charge.

Ion Channel

Selective gate that allows ions to pass through.

Electrostatic Pressure

Opposites attract, likes repel; charge attraction.

Diffusion

Spread out; molecules move to lower concentration.

Ligand

Binds to receptors, like a lock and key.

Ionotropic Receptor

Fast gate that directly opens ion channels.

Metabotropic Receptor

Signal relay that triggers a slower chain reaction.

G-Protein

Message helper that relays receptor signals.

Excitatory Postsynaptic Potential (EPSP)

Go signal that excites neuron to fire.

Inhibitory Postsynaptic Potential (IPSP)

Stop signal that inhibits neuron from firing.

Neural Integration

Combines inputs to decide firing, crucial for reaching threshold potential.