Question

3. Maya loves milkshakes, but every time she drinks one, she feels bloated and has stomach cramps. Her friend Alex drinks the same milkshake with no problems. In science class, Maya learns that this difference has to do with enzymes and how our bodies digest milk.

Milk contains a sugar called ( ) that must be broken down by an enzyme called ( ) in order to be absorbed by the small intestine. Some people’s bodies stop producing this enzyme after early childhood, meaning the sugar in milk ( ) and becomes food for bacteria in the small intestine. This process produces ( ) , causing bloating, cramps, and discomfort. People who continue making the lactase enzyme throughout life have a genetic trait known as ( ).

Answer 1

Milk contains a sugar called lactose that must be broken down by an enzyme called lactase in order to be absorbed by the small intestine. Some people’s bodies stop producing this enzyme after early childhood, meaning the sugar in milk remains undigested and becomes food for bacteria in the small intestine. This process produces gas (e.g., hydrogen, methane, carbon dioxide), causing bloating, cramps, and discomfort. People who continue making the lactase enzyme throughout life have a genetic trait known as lactase persistence.