Question

Lactase is found in:
A. Saliva
B. Bile
C. Pancreatic juice
D. Intestinal juice

Answer 1

Lactase is responsible for breaking down lactose into its two basic sugars, glucose and galactose. Lactose can be processed and used by the body after it is broken down into simple sugars in the small intestine. Lactose can pass through the digestive tract without being absorbed if it is not broken down.

Complete explanation:
Option A: The main enzyme in the saliva is salivary amylase. Salivary amylase is a digestive enzyme that breaks down carbohydrates into smaller molecules, such as sugars. Lingual lipase is a salivary enzyme that catalyses the digestion of lipids by breaking down triglycerides into glycerides and fatty acid components.
Hence, option A is incorrect.
Option B: The liver manufactures bile, which is a digestive juice. The bile has no enzymes. Even though it lacks digestive enzymes, it plays an important role in fat digestion. Bile salts like bilirubin and biliverdin can be found in bile juice. Big fat globules are broken down into smaller globules so pancreatic enzymes can quickly work on them.
Hence, option B is incorrect.
Option C: Exocrine glands in the pancreas produce enzymes that aid in digestion. These enzymes encompass trypsin and chymotrypsin for protein digestion, amylase for carbohydrate digestion, and lipase for fat digestion.
Hence, option C is incorrect.
Option D: Lactase is an enzyme present in the human digestive system that is formed by the small intestine. It is essential to digest whole milk fully. Lactase is a digestive enzyme that breaks down lactose, a simple sugar that gives milk its sweetness.

Hence, option D is the correct answer.

Note:
Intestinal juice is clear to fade yellow, watery secretion composed of hormones, digestive enzymes, mucus, and neutralizing substances that are produced by the glands and mucous membrane lining of the small and large intestines. Intestinal juice helps digestion and absorption by neutralizing hydrochloric acid from the stomach, releasing gastrointestinal hormones into the bloodstream, and containing digestive enzymes. Hormones, the vagus nerve, and mechanical stimulation caused by the presence of food all affect the secretion of intestinal juice.