Biology — Receptor–Ligand Binding

K_d = \frac{[\text{R}][\text{L}]}{[\text{RL}]}

\theta = \frac{[\text{L}]}{K_d + [\text{L}]}

B = \frac{B_{max}[\text{L}]}{K_d + [\text{L}]}

\text{lower } K_d \Rightarrow \text{higher affinity}