Ion Transport Across Cell Membranes - Selective Permeability Explained #100299 (License: Personal Use)

The image illustrates two aqueous environments separated by a semipermeable membrane. On the left, ions (Na⁺, Cl⁻, H⁺) are uniformly distributed; on the right, the membrane allows only protons (H⁺) to pass, creating an ion gradient. This visual model clarifies concepts like electrochemical gradients, passive diffusion, and the role of membrane selectivity in biological systems.

Used in biology, physiology, or chemistry educational content-especially for explaining cell membrane function, nerve impulse transmission, or kidney filtration. Matches user intent for learning foundational biophysics or preparing for exams like AP Biology or MCAT.