Nutrition

Animals use the organs of their digestive systems to extract important nutrients from food they consume, which can later be absorbed.

Carbohydrates, which break down to glucose, are a major source of energy for humans, but are not an essential nutrient.

Fats store energy, facilitate absorption of fat-soluble vitamins, aid brain growth and development, and protect against many diseases.

Proteins are composed of 20 different amino acids, about half of which are essential, meaning they must be obtained from the diet.

Essential nutrients are those that cannot be created by an animal's metabolism and need to be obtained from the diet.