Catabolic processes include which of the following activities?

Catabolic processes involve the breakdown of larger molecules into smaller ones, releasing energy that can be used by the body. Each of the activities listed in the options reflects a catabolic process contributing to energy metabolism.

Using glycogen stores during exercise is a prime example of a catabolic process. Glycogen, which is stored in muscles and the liver, is broken down into glucose molecules that can be used for energy during physical activity.

Chewing food during digestion, while primarily a mechanical process, facilitates catabolism. The act of chewing breaks down food into smaller pieces, making it easier for enzymes to further break down the macronutrients into absorbable units. Although chewing itself isn't a catabolic process, it prepares food for subsequent catabolic enzymatic reactions.

Breaking down starch in the intestines is another clear illustration of catabolic activity. In this case, enzymes such as amylase convert the polysaccharide starch into simpler sugars like maltose and glucose, which can then be absorbed into the bloodstream for energy.

Thus, the inclusion of all these activities as catabolic processes highlights their interconnectedness in the overall metabolism of food and energy production in the body.