03 ⚖️ Governing Scientific Laws, Theorems & Mathematical Models:
★ Van 't Hoff Osmotic Equilibrium Principle: [ Formula: Ψ_cell = Ψ_s + Ψ_p ] Total cellular water potential (Ψ_cell) equals the sum of osmotic/solute potential (Ψ_s, negative) and hydrostatic turgor pressure potential (Ψ_p, positive). Water moves spontaneously from higher water potential (dilute soil) to lower water potential (concentrated vacuolar sap).
★ Huxley Sliding Filament Theorem & All-or-None Law: [ Formula: F_twitch = max if V_stimulus ≥ V_threshold ] An individual skeletal muscle fiber or motor unit responds to an electrical stimulus maximally or does not respond at all. When activated, myosin heads hydrolyze ATP to form cross-bridges that slide actin filaments inward, narrowing the H-zone and I-band while keeping the A-band length constant.