1. for the exchange of ions 2. for making food 3. to grow 4. for balancing water and SALT balance 5. for nutirtion 6. for reparation 7. for respiration
the uses of metals and non metals in animals are 1. for nutrition 2. for DIGESTION of food 3. as medicines 4. as ADDITIVE in foods 5. for other biological PURPOSES such as respiration,transportation.