Energy flow and food chains
Structure and function · Biology
Study notes
Eating plants vs meat is an energy choice: ~90% of energy is lost per trophic level, so 1 kg of beef needs ~10 kg of grain — vegetarian diets feed more people per acre. DDT biomagnified up food chains — spraying killed mosquitoes but poisoned eagles (thinning eggshells), banning it saved raptors. Deep-sea vent chains run on chemical energy, not sunlight — life's alternate power grid.