ATI RN
Multiple Choice Questions on Endocrine System Questions
Question 1 of 5
An example of a hormone that under certain circumstances is regulated by positive feedback is:
Correct Answer: C
Rationale: Rationale: 1. Oxytocin is released during childbirth to stimulate uterine contractions. 2. As contractions increase, oxytocin secretion is further stimulated in a positive feedback loop. 3. This positive feedback mechanism amplifies the contractions until delivery. 4. Calcitonin regulates calcium levels, histamine is involved in allergic responses, and melatonin regulates sleep-wake cycles. Summary: - Calcitonin, histamine, and melatonin do not exhibit positive feedback regulation like oxytocin during childbirth.
Question 2 of 5
The hypersecretion of growth hormone leads to:
Correct Answer: C
Rationale: The correct answer is C: Acromegaly. Hypersecretion of growth hormone in adults leads to acromegaly, characterized by enlarged hands, feet, and facial features. This occurs due to excess GH after epiphyseal plate closure. A: Cretinism is caused by congenital hypothyroidism, not GH hypersecretion. B: Myxoedema is a severe form of hypothyroidism, not related to GH. D: Graves disease is an autoimmune disorder causing hyperthyroidism, not GH hypersecretion.
Question 3 of 5
Which gland is responsible for the production of insulin?
Correct Answer: D
Rationale: The correct answer is D: islets of Langerhans. These clusters of cells within the pancreas are responsible for producing insulin. Insulin is a hormone that regulates blood sugar levels. The ovaries (A) and testes (B) are not responsible for insulin production. The hypothalamus (C) plays a role in regulating many bodily functions, but it is not directly involved in insulin production.
Question 4 of 5
Which term describes the maintenance of a stable internal environment?
Correct Answer: C
Rationale: Homeostasis is the maintenance of a stable internal environment to support optimal physiological functioning. It involves mechanisms that regulate variables within a narrow range. Negative feedback is a key mechanism in maintaining homeostasis by counteracting deviations from set points. Positive feedback amplifies changes and is not involved in maintaining stability. Metabolism refers to the chemical processes in the body and is not specifically related to the maintenance of internal stability. Therefore, the correct answer is C (homeostasis) because it directly relates to the concept of maintaining a stable internal environment through regulatory mechanisms.
Question 5 of 5
A patient presents with a moon face, truncal obesity, hypertension, purple straiae, buffalo hump, fragile skin and impaired glucose tolerance. The opposite of the current increased levels of the prime hormone involved in this patient is seen in:
Correct Answer: A
Rationale: Step 1: Identify the symptoms described in the patient: Moon face, truncal obesity, hypertension, purple striae, buffalo hump, fragile skin, impaired glucose tolerance. Step 2: These symptoms are classic for Cushing's syndrome, which is caused by excess cortisol. Step 3: The opposite of increased cortisol levels is decreased cortisol levels. Step 4: Addison's disease is characterized by adrenal insufficiency, leading to decreased cortisol levels. Step 5: Therefore, the correct answer is A: Addison's disease. Summary: - B: Pheochromocytoma is a tumor of the adrenal medulla, causing excess catecholamines, not related to cortisol. - C: Hyperaldosteronism is excess aldosterone production, not related to cortisol. - D: Cushing's syndrome is characterized by excess cortisol, not the opposite.