Which of the following is a clinical manifestation of hyperthyroidism?

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: C

Rationale: The correct answer is C: Weakness and confusion. Hypoglycemia is characterized by low blood sugar levels, leading to inadequate glucose supply to the brain, resulting in symptoms like weakness and confusion. Choices A, B, and D are incorrect. Rapid, deep breathing is not typically a sign of hypoglycemia but can be seen in other conditions like respiratory issues. Increased urination is more commonly associated with conditions like diabetes mellitus, while high blood pressure is not a typical sign of hypoglycemia.

Correct Answer: B

Rationale: The correct answer is B: Obstruction of the coronary arteries. Angina is primarily caused by a reduced blood flow to the heart due to blockages or narrowing in the coronary arteries. Choice A is incorrect because while increased oxygen demand can contribute to angina symptoms, it is not the primary cause. Choice C is incorrect as angina is not caused by a lack of oxygen in the lungs. Choice D is also incorrect as angina is not related to decreased blood supply to the liver.

Correct Answer: B

Rationale: The correct answer is B: Autoimmune destruction of the thyroid gland. In hypothyroidism, the thyroid gland does not produce enough hormones to meet the body's needs. This can be due to autoimmune destruction of the thyroid gland, where the body's immune system mistakenly attacks the thyroid tissue. Choices A, C, and D are incorrect. Overproduction of cortisol is associated with conditions like Cushing's syndrome, overactivity of the thyroid gland is a characteristic of hyperthyroidism, and insufficient iodine intake can lead to goiter but not necessarily hypothyroidism.

Correct Answer: A

Rationale: The correct answer is A: Erythropoietin. The kidneys produce erythropoietin to stimulate the production of red blood cells. Insulin and glycogen are not hormones secreted by the kidneys; insulin is produced by the pancreas, and glycogen is a stored form of glucose. Testosterone is a hormone primarily produced by the testes in males and to a lesser extent in females. Thyroid stimulating hormone is produced by the pituitary gland to regulate thyroid function, not red blood cell production.