Digestion and absorption practice · Medium

The correct answer is B (In human being, four pair of salivary gland secretes saliva) because humans have three pairs of major salivary glands: parotid, submandibular, and sublingual.

Option D (Vitamin-C) is correct because Vitamin C is both water-soluble and an antioxidant.

Option C (Amylase) is correct because amylase is secreted in saliva and pancreatic juice, not as a brush-bordered enzyme on the intestinal lining.

The correct answer is D (Above pH 5) because pepsin is most active in a highly acidic environment (pH 1.5-2.5) and becomes inactive at a pH above 5.

Option D (Cutting) is correct because carnassial teeth are modified for shearing or cutting flesh.

Option B (Cholecystokinin) is correct because cholecystokinin stimulates the contraction of the gall bladder, leading to the release of bile.

Option A (Oxyntic cells - A secretion with pH between 2.0 and 3.0) is correctly matched because oxyntic cells secrete HCl, which creates a highly acidic environment with a pH between 2.0 and 3.0 in the stomach.

Option A (Enamel) is correct because enamel is the hardest substance in the body and forms the outer layer of the tooth, directly involved in the mastication (chewing) of food.

Option C (Cardiac sphincter) is correct because the cardiac sphincter prevents backflow from the stomach into the esophagus.

Option D (All of these) is correct because bile aids in fat digestion through emulsification, alkalinity, and micelle formation.

Option C (Proteases → Dipeptide) is correct because enterokinase activates trypsinogen to trypsin, which then activates other proteases.

Option C (Due to the bile pigment of bile juices) is correct because bilirubin, a bile pigment, is excreted in the stool, giving it a yellowish color.

Option A (Stomach, intestine and mouth, respectively) is correct because protein digestion starts in the stomach, fat digestion starts in the small intestine, and carbohydrate digestion starts in the mouth.

Option D (Sucrose) is correct because Ptyalin, Maltase, and Lactase are digestive enzymes, while Sucrose is a disaccharide.

Option D (If both Assertion and Reason are false) is correct because minerals are biologically active (e.g., enzyme cofactors), and copper deficiency can cause anemia.

Option D is correct because both the assertion and reason are true, and the reason correctly explains why proteins are called body-building biomolecules due to their role in metabolism and growth.

Option D (Salivary amylase → Pancreatic amylase → Disaccharidases) is correct because this is the correct sequence of enzyme action on carbohydrates as food moves through the alimentary canal.

Option A (Goat’s liver and spirulina) is correct because goat's liver and spirulina are known to be exceptionally rich sources of vitamin B12.

Option A (Gap between the teeth) is correct because diastema refers to a space or gap between two teeth, most commonly between the upper front incisors.

Option C is correct because both saturated and unsaturated fats can contribute to increased cholesterol levels in the blood, although saturated fats generally have a more significant impact.

Option D (Yeast) is correct because yeast is a good source of B vitamins but not Vitamin A, while carrots, mangoes, and apples contain Vitamin A or its precursors.

Option C (Glisson’s capsules and Kupffer’s cells) is correct because Glisson's capsule is a connective tissue layer surrounding the liver, and Kupffer's cells are specialized macrophages within the liver.

Option C (Colon) is correct because E. coli is a common bacterium found in the colon of the large intestine.

Option C (Enterokinase) is the odd one out because it is not a component of pancreatic juice itself, but rather an enzyme that activates trypsinogen, which is secreted by the pancreas.

Option B (Digestion and absorption of fat) is correct because bile salts emulsify fats, aiding both digestion and subsequent absorption.

Option D (Cholecystokinin) is correct because cholecystokinin stimulates both pancreatic secretion and gall bladder contraction.

Option C (Specific endopeptidases acting upon peptide & polypeptide chains) is correct because all three are endopeptidases that break internal peptide bonds.

Option C (Both (a) and (b)) is correct because both intrinsic and extrinsic neural systems control GI tract functions.

Option A (Six, four) is correct because trypsinogen, chymotrypsinogen, lipase, amylase, nucleases, and procarboxypeptidases are secreted by the pancreas, while nucleosidases, enteropeptidase, sucrase and lipase are secreted by the intestinal mucosa.

Option D (Bile) is correct because bile is synthesized in the liver, while chylomicrons, LDLs, and glycogen are synthesized in intestinal cells or liver cells.