4.7 Explain why only about 10% of energy is transferred from one trophic level to the next.

• Some energy is used at the current trophic level in life processes
• Some food the organism takes up is undigested and passed as faeces
• Organism might not eat everything (i.e. a rabbit won't eat a cabbage's roots, so won't gain 100% of its energy even if no energy was used by the cabbage)

4.6 Understand the transfer of substances and of energy along a food chain

When one organism eats another, the substances and energy from it get transferred to its consumer. I.e. if you eat a kilo of spinach, the energy and nutrients from that are transferred to you (don't try that please)

2.90 understand the sources, roles and effects of the following hormones: ADH, adrenaline, insulin, testosterone, progesterone and oestrogen

Basically everything you need to know is above, sorry if my handwriting is unreadable and messy ↑