पारिस्थितिकी तंत्र में ऊर्जा का प्रवाह किस दिशा में होता है?

उत्तर: (A) एकदिशीय / Unidirectional — Energy flow is unidirectional — from Sun → Producers → Primary consumers → Secondary consumers → Tertiary consumers. At each level, about 90% energy is lost as heat (10% rule). Energy doesn't cycle; n...