Final answer:
The FALSE statement about lysozyme is that it is not antimicrobial; in reality, lysozyme is a crucial antimicrobial enzyme found in saliva and part of the innate immune system.
Step-by-step explanation:
The statement that is FALSE about lysozyme is: 3) Lysozyme is not antimicrobial. In fact, lysozyme is an antimicrobial enzyme. Looking at the other options: 1) Lysozyme is indeed an enzyme; 2) It is found in saliva; and 4) Lysozyme is a type of protein. Therefore, among the provided statements, the third one is the incorrect statement about lysozyme.
Lysozyme plays a significant role in the first line of defense in the innate immune system by cleaving the B-(1,4) glycosidic linkages between N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) in bacterial peptidoglycan, which damages microbial cells. In the context of digestion, the salivary glands also produce other enzymes such as salivary amylase, which starts the digestion of carbohydrates, and lipase, which begins the breakdown of fats. Together, these enzymes contribute to the antimicrobial and digestive properties of saliva.