Digestive juices break down food into the tiniest nutrient components. Proteins are broken down to amino acids; fats are broken down to fatty acids and glycerol; and carbohydrates are broken down into simple sugars for absorption of these vital nutrients. The animal diet needs carbohydrates, protein, and fat, as well as vitamins and inorganic components for nutritional balance. Digestive enzymes are enzymes that break down polymeric macromolecules into their smaller building blocks, in order to facilitate their absorption by the body.
Eukaryotic cells do not have a nucleus. The nucleus is where DNA, your genetic material, is usually stored. Prokaryotic cells do not have a nucleus. The DNA just floats around the cell instead of staying in one designated area.