to Speak On Ava 1 Lily visits her family doctor because she experlences an upset stomach after drinking milk. The doctor teils her that this symptoms caused by a lack of the enzyme lactase. Lactase breaks down lactose, the sugar in milk which is made of several parts. What does lace breakdom monosaccharides B. amino acids C. fatty acids D. nucleotides Reset Next 2021 Edmentum. All rights reserved.