Athletes may take synthetic EPO to boost their

Correct Answer: C

Rationale: Erythropoietin (EPO), from kidneys, stimulates red blood cell production, increasing oxygen-carrying capacity enhancing endurance. It doesn't affect calcium, growth hormone, or muscle mass directly (testosterone does). Oxygen boost distinguishes EPO's use, key to athletic performance, contrasting with skeletal or hormonal growth effects.

Correct Answer: C

Rationale: Melatonin, from the pineal gland, regulates sleep-wake cycles, peaking in darkness to induce sleep, reducing arousal and cortisol darkness triggers, light inhibits it. The false statement reverses this: light suppresses melatonin, resetting circadian rhythms, while darkness stimulates it. Heat loss and rhythm regulation are true effects; pineal production is accurate. This light-dark dynamic distinguishes melatonin's role, critical for circadian alignment, unlike inverted or correct functions.

Correct Answer: C

Rationale: Addison's disease, adrenocortical insufficiency, causes glucocorticoid/mineralocorticoid deficiency, leading to muscle weakness, tiredness, hypoglycemia (not hyperglycemia), and menstrual issues from cortisol lack. Hyperglycemia aligns with excess cortisol (Cushing's). Hypoglycemia distinguishes Addison's metabolic impact, critical for recognizing adrenal failure, contrasting with sugar-elevating conditions.

Correct Answer: A

Rationale: Endocrine glands (e.g., thyroid) are ductless, releasing hormones into blood for distant targets, while exocrine glands (e.g., sweat) use ducts to surfaces or cavities. Hormones versus waste oversimplifies exocrine products (e.g., saliva) aren't just waste. Both gland types are epithelial, not connective for exocrine. Interconnection isn't universal endocrine glands (e.g., adrenals) act independently, like exocrine. Ductless blood delivery distinguishes endocrine function, key to systemic reach, unlike ducted or mischaracterized traits.

Correct Answer: C

Rationale: The posterior pituitary stores and releases oxytocin (labor, lactation) and ADH (water balance), both hypothalamic-made. Growth hormone and prolactin are anterior pituitary products, not stored posteriorly. Prolactin isn't posterior oxytocin fits. ADH with GH mixes lobes incorrectly. Oxytocin-ADH pairing distinguishes neurohypophyseal function, critical for hypothalamic delivery, unlike anterior hormones.