Food/Dietary constituents: are organic or inorganic constituents of food or diet ingested by man e.g. starch, proteins, fats, vitamins etc.
Carnivores: the animals who obtain their food by eating other animals e.g. cat, dog etc.
Herbivores: are the animals who obtain their food from plants or plant products e.g. cow, buffalo, horse, rabbit. Omnivores are the animals who partly obtain their food from plants and partly from animals e.g. man, poultry, pigs.