B.11B_Enzymes_approaching – 02
Each day on the way to lunch, Ben stops by the nurse’s office to take a pill. When asked why he needs the pill, Ben said that he is lactose intolerant. He gets an upset stomach when he eats or drinks dairy products. Lactose is a sugar molecule naturally found in milk. He said that the pill keeps him from getting sick when he eats ice cream during lunch. Most of his friends said that they know people who are also lactose intolerant. They do not understand exactly what that means. But they are happy that there is a pill that lets Ben eat his ice cream every day.
What Ben’s classmates may not know is the pill that he takes to digest lactose has a substance called lactase. The -ase ending in a name means that it is an enzyme. Enzymes belong to the group of molecules called catalysts. Catalysts are substances that speed up chemical reactions without being used up. Enzymes are catalysts that occur in all living things.
There are thousands of different enzymes in organisms. Some are digestive enzymes, like the lactase in Ben’s pill. They break down foods and nutrient molecules. Other enzymes control cellular processes that occur in organisms. Some of the processes build molecules. Other processes break molecules apart. DNA replication is a process that involve a series of reactions. It relies on many enzymes to control the reactions from start to finish.
