AP BIOLOGY

Detailed explanation-1: -Saliva contains special enzymes that help digest the starches in your food. An enzyme called amylase breaks down starches (complex carbohydrates) into sugars, which your body can more easily absorb.

Detailed explanation-2: -Answer and Explanation: The kidneys are not part of the digestive system.

Detailed explanation-3: -Option:C – Glucose is not present in saliva instead saliva contains amylase enzyme which breaks the starch in the food we eat to simpler fragments in the oral cavity initializing the process of digestion. Thus, this option is correct as glucose is not the constituent of saliva.

Detailed explanation-4: -It is composed of water, mucus, proteins, mineral salts, and amylase. As saliva circulates in the mouth cavity it picks up food debris, bacterial cells, and white blood cells. One to two litres of fluid are excreted daily into the human mouth.