science fusion grade 7
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7 - The animal in the picture is developing, which can be translated into growing. It does that with the nutrients and energy it obtains from food.
8 - So that our muscles and bones can grow and their cells can develop, we need energy and nutrients which are obtained through our digestive system (see metabolism) from the food we eat.
→ Metabolism is basically what was said above: the obtainment of nutrients and energy.
Hope it helped,
BioTeacher101