ANATOMY

Detailed explanation-1: -Large food molecules (for example, proteins, lipids, nucleic acids, and starches) must be broken down into subunits that are small enough to be absorbed by the lining of the alimentary canal. This is accomplished by enzymes through hydrolysis.

Detailed explanation-2: -Digestion is important for breaking down food into nutrients, which the body uses for energy, growth, and cell repair. Food and drink must be changed into smaller molecules of nutrients before the blood absorbs them and carries them to cells throughout the body.

Detailed explanation-3: -In either case, the large polymeric molecules in food are broken down during digestion into their monomer subunits-proteins into amino acids, polysaccharides into sugars, and fats into fatty acids and glycerol-through the action of enzymes.

Detailed explanation-4: -Lysosomes are membrane-enclosed organelles that contain an array of enzymes capable of breaking down all types of biological polymers-proteins, nucleic acids, carbohydrates, and lipids.

Detailed explanation-5: -Along the way, food is broken down into tiny molecules so that the body can absorb nutrients it needs: Protein must be broken down into amino acids. Starches break down into simple sugars. Fats break down into into fatty acids and glycerol.