The 'ball' of food that is swallowed and moved through the esophagus is called the

Correct Answer: C

Rationale: The correct answer is C: bolus. A bolus refers to the rounded mass of food that is formed in the mouth and swallowed, moving through the esophagus to the stomach. This process is essential for digestion to occur properly. Choice A, sphincter, is incorrect as it is a muscular ring that regulates the flow of substances. Choice B, cannula, is a tube used for medical purposes, not related to food digestion. Choice D, chyme, is the partially digested food mixed with stomach acid, not the initial mass of food swallowed.

Correct Answer: A

Rationale: Step-by-step rationale for choice A: 1. A chronic productive cough is a key symptom of COPD due to excess mucus production. 2. This cough is persistent and lasts for a prolonged period, reflecting airway inflammation. 3. Productive cough is often associated with sputum production in COPD patients. 4. The presence of a chronic productive cough aligns with the pathophysiology of COPD. Summary of why other choices are incorrect: B: A nocturnal cough may be seen in conditions like asthma but is not specific to COPD. C: A wheeze is more common in asthma and may occur in COPD exacerbations, but not a consistent feature. D: COPD typically develops after years of exposure to risk factors, so onset at 25 years old is unlikely.

Correct Answer: C

Rationale: The correct answer is C: Diabetic retinopathy. This is a microvascular complication of diabetes mellitus affecting the small blood vessels in the retina. It is caused by prolonged high blood sugar levels damaging the blood vessels, leading to vision problems and potentially blindness. Explanation: 1. Diabetic retinopathy specifically involves the microvasculature of the eye. 2. Abdominal aortic aneurysm (Choice A) and Coronary heart disease (Choice B) are macrovascular complications affecting larger blood vessels. 3. Peripheral artery disease (Choice D) involves blockages in larger arteries, not the microvasculature. In summary, diabetic retinopathy is the best description of a microvascular complication of diabetes mellitus as it involves damage to the small blood vessels in the retina, distinguishing it from macrovascular complications listed in the other options.

Correct Answer: C

Rationale: The correct answer is C: Peak flow <33% of normal. This indicates severe airflow obstruction. A: Hypotension is a sign of severe asthma but not specific enough to categorize it as severe. B: Peak flow <50% indicates moderate exacerbation. D: Bradycardia is not typically associated with asthma exacerbation. Therefore, C is the most appropriate choice because it directly reflects the severity of the patient's condition.

Correct Answer: C

Rationale: The correct answer is C. Eradication of H. pylori prevents adenocarcinoma of the stomach. This statement is incorrect because eradication of H. pylori has been shown to decrease the risk of gastric cancer but does not completely prevent it. A: H. pylori can invade the gastric epithelium, leading to inflammation. B: H. pylori actually reduces gastric acid secretion to help it survive in the stomach. D: H. pylori does produce urease, which helps it survive in the acidic stomach environment by neutralizing urea into ammonia and CO2.