The receptors for non-steroid peptide hormones are found on the ______.

Correct Answer: A

Rationale: The receptors for non-steroid peptide hormones are typically found on the plasma membrane of target cells. These hormones are large or polar molecules that cannot easily diffuse through the cell membrane. Instead, they bind to specific receptors on the cell surface, initiating signaling pathways that eventually lead to changes within the cell. Once the peptide hormone binds to its receptor on the plasma membrane, secondary messenger systems are activated to relay the signal into the cell and initiate the appropriate cellular response. This distinct mechanism of action highlights the importance of the plasma membrane as the location of receptors for non-steroid peptide hormones.

Correct Answer: B

Rationale: Pseudohypoparathyroidism is a rare genetic disorder that mimics the symptoms of hypoparathyroidism, despite normal or elevated levels of parathyroid hormone (PTH). The condition is characterized by hypocalcemia, hyperphosphatemia, and normal or elevated PTH levels. However, it is not associated with a raised level of plasma PIH (Parathyroid Inhibiting Hormone). In pseudohypoparathyroidism, the body's tissues are resistant to the action of PTH, leading to impaired calcium regulation. Other common features of pseudohypoparathyroidism may include cataract formation, mental retardation, and reduced levels of plasma phosphate.

Correct Answer: B

Rationale: Excess prolactin typically causes gynecomastia in men. Prolactin is a hormone primarily responsible for milk production in women. However, in men, elevated levels of prolactin can lead to various symptoms, with gynecomastia being one of the most common. Gynecomastia is the development of breast tissue in males, which can result in swelling and tenderness of the breasts. It is important to investigate the underlying cause of elevated prolactin levels as it could be due to various conditions such as pituitary tumors, certain medications, or thyroid disorders.

Correct Answer: B

Rationale: Conn's syndrome, also known as primary hyperaldosteronism, is characterized by excess production of aldosterone by the adrenal glands. This leads to increased sodium retention and potassium excretion in the kidneys. As a result, patients with Conn's syndrome typically present with hypokalemia (low potassium levels), not hyperkalemia (high potassium levels). The other features of Conn's syndrome include alkalosis (metabolic), muscle cramps, and severe systemic hypertension.

Correct Answer: A

Rationale: Acromegaly most commonly affects individuals in the age group of 30-50 years. This condition is typically diagnosed in adults between these ages. Acromegaly is often caused by the overproduction of growth hormone in adults, which leads to excessive bone growth and tissue expansion. While acromegaly can develop at any age, it is more commonly seen in adults within the 30-50 age range.

Correct Answer: A

Rationale: Phaeochromocytoma may be associated with Medullary carcinoma of thyroid, Hyperparathyroidism, and Addison's disease as part of MEN Syndrome (Multiple Endocrine Neoplasia) Type 2. However, it is not typically associated with Neurofibromatosis. Neurofibromatosis is associated with the development of benign tumors of nerve tissue and is not directly linked to the presence of Phaeochromocytoma.

Correct Answer: A

Rationale: Addison's disease, also known as primary adrenal insufficiency, is a condition where the adrenal glands do not produce enough steroid hormones, mainly cortisol and sometimes aldosterone. This deficiency in steroid hormone production is typically caused by autoimmune destruction of the adrenal cortex. Without enough cortisol and aldosterone, various symptoms may arise, such as fatigue, weight loss, low blood pressure, and skin discoloration. Therefore, option A accurately describes the nature of Addison's disease.

Correct Answer: B

Rationale: Small cell (oat cell) carcinoma of the lung is most commonly associated with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). This paraneoplastic syndrome occurs in patients with small cell lung cancer due to the production of antidiuretic hormone (ADH) by the tumor cells. The excessive release of ADH leads to water retention and dilutional hyponatremia, causing symptoms such as nausea, confusion, seizures, and potentially life-threatening complications. Other types of lung cancer, such as squamous cell carcinoma, large cell carcinoma, and adenocarcinoma, are less commonly associated with SIADH.

Correct Answer: D

Rationale: Obesity is associated with an increased risk of developing various health conditions, including diabetes mellitus, cancer, and hypertension. However, chronic obstructive lung disease (COPD) is not directly linked to obesity. COPD is primarily caused by exposure to harmful particles or gases, most commonly from cigarette smoke. While obesity can impact lung function and worsen symptoms in individuals with COPD, it is not a direct cause of the condition. Therefore, the correct answer is D, chronic obstructive lung disease.