Final answer:
The oral cavity primarily uses the enzyme amylase to break down carbohydrates, starting with complex starches into smaller sugar molecules like maltose. Proteins and lipids are not digested in the oral cavity, with proteins being digested by pepsin in the stomach.
Step-by-step explanation:
The oral cavity utilizes several enzymes to begin the process of digestion. The primary enzyme found in saliva is amylase, which is instrumental in the chemical digestion of carbohydrates. Amylase starts the breakdown of complex carbohydrates into smaller sugar molecules like maltose. Contrary to the incorrect information that amylase breaks down proteins, its actual role is specific to carbohydrates. Saliva also contains an enzyme called maltase that further aids in carbohydrate digestion within the oral cavity.
Although not part of the oral cavity, the stomach uses an enzyme called pepsin, which is involved in protein digestion, breaking down protein molecules into amino acids. It is important to note that lipases, which break down lipids, and proteases, which break down proteins, are also present in the digestive system but are not active in the oral cavity.
Overall, the salivary enzymes (mainly amylase and maltase) play an essential role in initiating the digestion of carbohydrates, preparing them for further breakdown and absorption in the small intestine.