C2.2 (Neural Signalling)

Neuron

A specialised cell that receives, processes and transmits electrical or chemical signals.

Nerve Fiber

A long projection of a neuron, usually an axon, that carries nerve impulses.

Dendrite

Branched neuron extension that receives signals from other cells and carries them toward the cell body.

Axon

Long neuron projection that carries nerve impulses away from the cell body.

Axon Terminal

End of an axon where neurotransmitters are released to communicate with another cell.

Sensory Neuron

Neuron that carries impulses from sensory receptors to the central nervous system.

Interneuron

Neuron within the central nervous system that connects sensory and motor neurons.

Sensory Neuron

Neuron that carries impulses from sensory receptors to the central nervous system.

Resting Potential

Electrical potential difference across a neuron's membrane when it is not transmitting an impulse.

Sodium-Potassium Pump

Membrane protein that uses ATP to actively transport Na⁺ out of the neuron and K⁺ into it.

Nerve Impulse

Electrical signal transmitted along a neuron.

Action Potential

Rapid, temporary change in membrane potential that travels along an axon.

Myelin

Lipid-rich insulating material surrounding some axons, increasing the speed of nerve impulse transmission.

Myelinated Axons

Axons surrounded by a myelin sheath, allowing impulses to travel rapidly between nodes of Ranvier.

Non-myelinated Axons

Axons without a myelin sheath, where impulses travel continuously along the membrane.

Correlation

A statistical relationship showing how two variables change in relation to each other; it does not necessarily indicate causation.