Digestion, enzyme, catalyst, amylase, maltose, oesophagus, peristalsis, fibre, stomach, organ, small intestine, liver, bile, pancreas, large intestine, faeces, egestion, plasma, haemoglobin, antibodies, platelets, arteries, veins, capillaries, cardiac, pulse, atria, ventricles, pulmonary, inhale, exhale, respiration, excretion, trachea, bronchus, bronchiole, alveolus, diaphragm, health, single – gene disorder, multi gene disorder, balanced diet, food pyramid, energy value, micro- organisms, pathogens, viruses, parasites, antibodies, bacteria, antibiotics, fungi, immunisation, vaccination