Anatomy & Physiology Part 5: The Nervous System & Sensory Organs

An advanced quiz on the body's command center and its detectors.

📖 Core Concepts Review

SystemComponentPrimary FunctionKey Concepts
⚡ Nervous SystemNeuron & SynapseTransmit electrical & chemical signalsAction Potential, Myelin, Neurotransmitters
🧠 CNS vs. PNSDivisionsCNS integrates; PNS communicatesBrain, Spinal Cord, Nerves
☯️ Autonomic NSSympathetic vs. ParasympatheticControls involuntary actionsFight-or-Flight vs. Rest-and-Digest
👁️ Sensory OrgansEye & EarTransduce physical stimuli into nerve signalsRods/Cones (Vision), Cochlea/Vestibular System (Hearing/Balance)

Problem 1: The Action Potential

Medium
Nervous SystemAction PotentialIons

An action potential is a rapid, all-or-nothing electrical impulse. The repolarization phase (the falling phase) is primarily caused by what ionic movement?

A

The rapid influx of sodium ions (Na⁺) into the cell.

B

The slow closing of potassium ion (K⁺) channels.

C

The rapid efflux of potassium ions (K⁺) out of the cell.

D

The influx of chloride ions (Cl⁻) into the cell.