ECO-01 Five Must-Know Facts

Pyramid of energy is ALWAYS upright — no exception exists; this is the most-tested single ecology fact in NEET.
Logistic growth equation: dN/dt = rN $\frac{K−N}{K}$ ; maximum growth rate at N = K/2 — the inflection point of the sigmoid curve.
Phosphorus cycle has NO gaseous phase — it is the only major biogeochemical cycle that is purely sedimentary.
Pioneer species in primary succession on bare rock = crustose lichens — not mosses, not grasses.
NPP = GPP − Respiration — the energy available to herbivores, not gross production; energy flow is unidirectional (10% law, Lindeman).