Cooperative Binding — Hill Equation & Hemoglobin

Oxygen Dissociation Curves — θ(pO₂)

Hill plot — ln(θ/(1-θ)) vs ln(pO₂)

MWC model — subunit states

Bohr effect (pH shift)

Free energy landscape

Hill exponent n 2.70 Half-saturation P₅₀ (mmHg) 26.0 pH (Bohr effect) 7.40 Temperature T (°C) 37.0 MWC ratio L (T/R states) 2000

Cooperative binding: Hill equation θ = pO₂ⁿ/(P₅₀ⁿ + pO₂ⁿ). Hemoglobin (n≈2.7, P₅₀≈26 mmHg) loads O₂ in lungs (100 mmHg) and unloads in tissues (40 mmHg). Bohr effect: H⁺ and CO₂ shift P₅₀ rightward (deoxygenation where needed). MWC model: n subunits in T (tense, low affinity) or R (relaxed, high affinity) states — allosteric cooperativity emerges.
Delivery efficiency: — % | O₂ loading: —% | O₂ unloading: —%