Mucus is produced by the salivary glands and the:

Correct Answer: A

Rationale: Mucus is produced by the salivary glands to moisten food and aid in swallowing. Additionally, the intestinal glands secrete mucus to protect the lining of the intestines. The other choices, esophageal glands, pineal gland, and islets of Langerhans, are not involved in the production of mucus in the digestive system.

Correct Answer: B

Rationale: The correct answer is B: nonessential amino acids. Nonessential amino acids can be synthesized by the body, so they do not need to be obtained through the diet. Essential amino acids, choice A, must be obtained from the diet because the body cannot produce them. Choices C and D, complete and incomplete amino acids respectively, do not accurately describe the classification of amino acids based on synthesis by the body.

Correct Answer: A

Rationale: Mucus is produced by the salivary glands to moisten food and aid in swallowing. Additionally, the intestinal glands secrete mucus to protect the lining of the intestines. The other choices, esophageal glands, pineal gland, and islets of Langerhans, are not involved in the production of mucus in the digestive system.

Correct Answer: C

Rationale: Probiotics are live bacteria that are beneficial for gut health and are often taken as supplements. They are not indigestible carbohydrates (Choice A), antibiotics (Choice B), or commercial fiber supplements (Choice D). Probiotics contain live strains of good bacteria that help maintain a healthy balance in the gut microbiome.

Correct Answer: A

Rationale: The correct answer is A: kwashiorkor. Kwashiorkor is a form of protein-energy malnutrition that arises due to a protein-deficient diet. This condition leads to symptoms such as edema, skin lesions, and fatty liver. Choice B, marasmus, is a form of PEM caused by overall malnutrition (protein and calorie deficiency), resulting in severe wasting and muscle loss. Choice C, anemia, is a condition characterized by a deficiency of red blood cells or hemoglobin, not specifically related to protein deficiency. Choice D, beriberi, is a disease caused by thiamine (Vitamin B1) deficiency, not a form of PEM related to protein deficiency.

Correct Answer: A

Rationale: Bacteria found in the colon are important because they synthesize important vitamins, such as vitamin K. This aids in the body's overall health and functioning. Choice B is incorrect because absorption primarily occurs in the small intestine, not the colon. Choice C is incorrect as the synthesis of minerals is not a primary function of colon bacteria. Choice D is incorrect as the digestion process mainly occurs in the stomach and small intestine.

Correct Answer: D

Rationale: Eggs are considered a source of complete protein because they contain all the essential amino acids required by the body. The other options, cereal grains, beans, and nuts, do not provide all the essential amino acids in the necessary proportions to be classified as complete proteins.

Correct Answer: B

Rationale: The correct answer is B: Presence of fat in the duodenum. Cholecystokinin (CCK) is released in response to the presence of fat in the duodenum to aid in digestion by stimulating the release of bile from the gallbladder and enzymes from the pancreas. Options A, C, and D are incorrect because CCK is specifically released in response to the presence of fat in the duodenum, not food in the stomach, acid chyme in the ileum, or bile in the gallbladder.

Correct Answer: D

Rationale: The correct answer is D: gastroesophageal reflux disease (GERD). GERD occurs when stomach acid flows back into the esophagus, causing symptoms like heartburn and regurgitation. Choice A, hiatal hernia, is a condition where part of the stomach pushes up into the chest through an opening in the diaphragm. Choice B, diverticulitis, is inflammation or infection of small pouches that can form in the lining of the digestive system. Choice C, gastroenteritis, is inflammation of the stomach and intestines typically caused by a viral or bacterial infection. Therefore, only choice D accurately describes the regurgitation or reflux of acidic stomach contents back into the esophagus.