Same chapter3 marksDifficulty: Medium
Describe the carbon cycle in outline.
Ecosystem
3 marksDifficulty: Medium
Explain the ten per cent law and why ecological pyramids of energy are always upright.
Original Khojo Papers practice question — not from a past board paper.
Answer
Only about ten per cent of the energy at one trophic level is passed on to the next, the rest being lost as heat in respiration and in the incomplete consumption and digestion of the food. Because energy is lost at every transfer and can never increase upwards, a pyramid of energy is always upright.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Pyramids of number and of biomass can be inverted, but a pyramid of energy cannot.
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