Vitamins furnish additional lubrication and grease to allow efficient functioning. Water provides all the interlinking support systems like electrical, cooling, braking, exhaust, etc. All physical and chemical processes used to break down the feed and make it ready for absorption. Elements of the digestive process. Particle size reduction increases the surface area of feedstuffs.
Enzymes are organic catalysts.
Nutrients and their components. Carbohydrates are composed of simple sugars. Proteins are composed of amino acids. Digestive System Organs and their functions. Beak and mouthparts merely pick up feed particles and force them down throat.