The digestive system:

provides body with nutrients, water, and minerals.

Alimentation:

process of providing nutrition for the body

4 main digestive activities

Ingestion, digestion, absorption, and elimination

Ingestion (1)

oral intake of substances into body

Digestion (2)

mechanical and chemical conversion of food into substances that are eventually absorbed by cells.

Absorption (3)

process in which the digested food molecules pass through the lining of the small intestine into the blood or lymph capillaries.

Elimination (4)

removal of undigested food particles and defection, elimination of waste in the form of feces.

3 major classes of nutrients

Carbohydrates, proteins, and lipids.