Correct Answer: A

Rationale: Dermal hyperpigmentation, also known as hyperpigmentation of the skin, is commonly associated with conditions such as Addison's disease, hemochromatosis, and bronchogenic carcinoma. In Addison's disease, there is increased production of melanin due to elevated levels of adrenocorticotropic hormone (ACTH) which stimulates melanocytes. Hemochromatosis can cause hyperpigmentation due to excess iron deposits in the skin. Bronchogenic carcinoma can lead to a condition known as acanthosis nigricans, characterized by dark, velvety discoloration of the skin primarily around the neck and armpits. However, Conn's syndrome, which is a primary aldosteronism resulting from an adrenal adenoma or hyperplasia, is not typically associated with dermal hyperpigmentation.

Correct Answer: C

Rationale: Polycystic ovarian disease, also known as polycystic ovary syndrome (PCOS), is a common endocrine disorder characterized by increased levels of androgens (male hormones) and disrupted estrogen production in the ovaries. The hormonal imbalance seen in PCOS leads to increased gonadal production of estrogen. This condition is often associated with symptoms such as irregular menstrual cycles, infertility, acne, and excess facial or body hair growth. In contrast, the other options do not typically involve increased gonadal production of estrogen as seen in PCOS.

Correct Answer: D

Rationale: Oxytocin and antidiuretic hormone (ADH; vasopressin) are both synthesized in the hypothalamus, specifically in the supraoptic and paraventricular nuclei. After synthesis, they are transported along axons to the posterior pituitary where they are stored until they are released into the bloodstream when needed. This is why they are released from the posterior pituitary, not the anterior pituitary. These hormones have different functions in the body, with oxytocin being involved in labor and breastfeeding, while ADH plays a role in regulating water balance and blood pressure.

Correct Answer: A

Rationale: Cushing's syndrome is a condition characterized by excessive levels of cortisol in the body. Cortisol is a hormone produced by the adrenal glands that helps regulate various bodily functions, including metabolism, immune response, and stress response. When there is an overproduction of cortisol, either due to excessive production by the adrenal glands or prolonged use of corticosteroid medications, it can result in Cushing's syndrome. Symptoms of Cushing's syndrome include weight gain, particularly in the face and abdomen, high blood pressure, muscle weakness, and irregularities in menstruation. It is important to diagnose and manage Cushing's syndrome to prevent potential complications such as diabetes, osteoporosis, and cardiovascular disease.

Correct Answer: B

Rationale: In males, Leydig cells in the testes are stimulated to produce testosterone by luteinizing hormone (LH). LH is produced by the anterior pituitary gland and acts on the Leydig cells to promote the synthesis and release of testosterone. This hormone plays a crucial role in male reproductive function and the development of masculine characteristics. Follicle stimulating hormone (FSH) plays a role in spermatogenesis in males but does not directly stimulate Leydig cells to produce testosterone.