Nokea
Which of these ingredients in saliva is responsible for activating salivary amylase?
- A. mucus
- B. phosphate ions
- C. chloride ions
- D. urea
Correct Answer: B
Rationale: The correct answer is B: phosphate ions. Phosphate ions present in saliva help activate salivary amylase by providing the necessary environment for the enzyme to function optimally. Salivary amylase works best at a slightly alkaline pH, which is facilitated by the presence of phosphate ions. Mucus (choice A) primarily helps with lubrication and binding of food particles but does not activate enzymes. Chloride ions (choice C) are not directly involved in activating salivary amylase. Urea (choice D) is a waste product and not related to enzyme activation in saliva. In summary, the correct answer is B because phosphate ions create the optimal pH environment for salivary amylase activity, while the other choices are not directly involved in enzyme activation.
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The coronary ligament attaches the
- A. liver to the diaphragm.
- B. liver to the anterior abdominal wall.
- C. colon to the posterior body wall.
- D. lesser curvature of the stomach and proximal end of the duodenum to the liver and diaphragm.
Correct Answer: A
Rationale: The correct answer is A because the coronary ligament attaches the liver to the diaphragm. This ligament forms part of the peritoneal ligaments that secure the liver to the diaphragm, supporting its position in the abdominal cavity. The other choices are incorrect because: B) The liver is attached to the anterior abdominal wall by the falciform ligament, not the coronary ligament. C) The colon is attached to the posterior body wall by the mesocolon, not the coronary ligament. D) The lesser curvature of the stomach and proximal end of the duodenum are attached to the liver and diaphragm by the lesser omentum, not the coronary ligament.
What contributes to increased protein-calorie needs?
- A. Surgery
- B. Vegan diet
- C. Lowered temperature
- D. Cultural or religious beliefs
Correct Answer: A
Rationale: The correct answer is A: Surgery. Surgery increases protein-calorie needs due to the body's increased demand for nutrients to support healing and recovery. The body requires more protein and calories to repair tissues and maintain immune function post-surgery.
Choice B: A vegan diet does not necessarily contribute to increased protein-calorie needs as it is possible to meet nutritional requirements with proper planning.
Choice C: Lowered temperature does not directly affect protein-calorie needs.
Choice D: Cultural or religious beliefs do not inherently increase protein-calorie needs, as dietary choices can still meet nutritional requirements.
Which hormone stimulates the release of digestive enzymes from the pancreas?
- A. Insulin
- B. Glucagon
- C. Secretin
- D. Cholecystokinin (CCK)
Correct Answer: D
Rationale: The correct answer is D, Cholecystokinin (CCK). CCK is produced in the small intestine in response to the presence of fats and proteins. It stimulates the release of digestive enzymes from the pancreas to aid in digestion. Insulin (A) and Glucagon (B) are involved in regulating blood sugar levels, not digestive enzyme release. Secretin (C) primarily stimulates the release of bicarbonate from the pancreas to neutralize stomach acid, not digestive enzymes.
What role do the teeth play in digestion?
- A. chemical digestion
- B. mechanical digestion
- C. enzymatic digestion
- D. absorption
Correct Answer: B
Rationale: The correct answer is B: mechanical digestion. Teeth play a crucial role in breaking down food into smaller pieces through physical chewing, which is a form of mechanical digestion. This process increases the surface area of food particles, making it easier for enzymes to further break down nutrients during chemical digestion in the stomach and intestines. Choice A (chemical digestion) is incorrect because teeth do not directly participate in chemical breakdown of food. Choice C (enzymatic digestion) is incorrect as enzymes are not produced by teeth but by salivary glands and other digestive organs. Choice D (absorption) is incorrect as teeth are not involved in absorbing nutrients; absorption primarily occurs in the small intestine.
Which of the following cells in the stomach secrete pepsinogen?
- A. parietal cells
- B. chief cells
- C. mucous neck cells
- D. enteroendocrine cells
Correct Answer: B
Rationale: The correct answer is B: chief cells. Chief cells are responsible for secreting pepsinogen in the stomach. Pepsinogen is an inactive form of pepsin, which is an enzyme that helps in protein digestion. Parietal cells secrete hydrochloric acid, not pepsinogen. Mucous neck cells secrete mucus to protect the stomach lining. Enteroendocrine cells secrete hormones like gastrin, but not pepsinogen. Therefore, the correct answer is B as chief cells are the specific cells that secrete pepsinogen in the stomach.