What causes osteoporosis?

Correct Answer: C

Rationale: The correct answer is C. Osteoporosis is commonly caused by bone loss that occurs with aging, leading to brittle bones. Choice A, poor nutrition in infancy, is not a direct cause of osteoporosis. Choice B, regularly weight-bearing exercise, actually helps in maintaining bone density and strength, reducing the risk of osteoporosis. Choice D, cerebral palsy and associated disorders, is not a common cause of osteoporosis.

Correct Answer: B

Rationale: Passive immunity is the transfer of pre-formed antibodies from one individual to another, providing immediate but temporary protection. In this case, the correct answer is the transfer of antibodies from the mother to the baby, as it describes the concept of passive immunity. Choice A, vaccination against the disease, refers to active immunity where the individual's immune system is stimulated to produce antibodies. Choice C, cuts or wounds that are infected and heal, is unrelated to immunity. Choice D, having the disease in question, does not describe passive immunity but rather acquiring active immunity through exposure to the pathogen.

Correct Answer: C

Rationale: The correct answer is C: Appendicitis. The symptoms described - lower right quadrant abdominal pain, fever, nausea, diarrhea, and tenderness upon palpation - are classic signs of appendicitis. Appendicitis is an inflammatory condition of the appendix that often presents with these symptoms and requires immediate medical attention. Choice A, Pseudomembranous colitis, typically presents with watery diarrhea and is associated with antibiotic use. Choice B, Peptic ulcer disease, commonly presents with epigastric pain related to meals and can be accompanied by nausea or vomiting, but it does not typically cause right lower quadrant pain. Choice D, Esophageal cancer, usually presents with symptoms related to swallowing difficulties, weight loss, and sometimes chest pain, but it is not associated with the symptoms described in the scenario.

Correct Answer: A

Rationale: The correct answer is A: Tachycardia. Tachycardia, which is an increased heart rate, is a classic clinical manifestation of hyperthyroidism. In hyperthyroidism, there is an excess production of thyroid hormones, leading to an increased metabolic rate. This increased metabolism can cause symptoms such as a rapid heart rate. Choices B, C, and D are incorrect because constipation, weight gain, and fatigue are more commonly associated with hypothyroidism, where there is a deficiency of thyroid hormones leading to a slower metabolic rate.

Correct Answer: A

Rationale: The correct answer is A. Persistent chest pain that may radiate to the arm is a classic symptom of myocardial infarction. This pain is typically described as crushing, pressure-like, or squeezing. Choice B is incorrect because brief sternal chest pain on inspiration is not characteristic of myocardial infarction. Choice C is incorrect because rapid respirations with left-sided weakness and numbness are not typical symptoms of myocardial infarction. Choice D is incorrect because left upper quadrant abdominal pain that radiates to the back and shoulder is not a common presentation of myocardial infarction.