Nokea
Which of the following is NOT true of parathyroid hormone action?
- A. Releases calcium from bone to raise blood calcium levels.
- B. Decreases blood calcium levels.
- C. Promotes reabsorption of calcium in the kidneys to raise blood calcium levels.
- D. Activates Vitamin D to increase calcium absorption from nutrients in the intestines.
Correct Answer: B
Rationale: The correct answer is B because parathyroid hormone (PTH) actually increases blood calcium levels. PTH achieves this by releasing calcium from bone (A), promoting reabsorption of calcium in the kidneys (C), and activating Vitamin D for increased calcium absorption in the intestines (D). By decreasing blood calcium levels, it would go against the primary function of PTH. This choice is incorrect as PTH is known for its role in increasing blood calcium levels through the mentioned mechanisms.
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The most appropriate drug for treating myasthenia gravis is:
- A. Neostigmine
- B. Pilocarpine
- C. Succinylcholine
- D. Tubocurarine
Correct Answer: A
Rationale: Neostigmine is the correct choice for treating myasthenia gravis as it is an acetylcholinesterase inhibitor that increases acetylcholine levels, improving muscle strength. Pilocarpine is a muscarinic agonist used for glaucoma. Succinylcholine is a depolarizing neuromuscular blocker used for intubation. Tubocurarine is a non-depolarizing neuromuscular blocker.
Adrenaline can be used in the following EXCEPT:
- A. Allergic reactions
- B. Acute bronchial asthma
- C. Complete heart block
- D. Angina pectoris
Correct Answer: D
Rationale: Adrenaline is a sympathomimetic drug that acts on adrenergic receptors. In acute situations like allergic reactions, bronchial asthma, and heart block, adrenaline can be beneficial due to its bronchodilator and vasoconstrictor effects. However, in angina pectoris, which is caused by reduced blood flow to the heart muscle, the vasoconstrictor effect of adrenaline can worsen the condition by increasing the workload of the heart. Therefore, adrenaline should not be used in angina pectoris.
Bronzing:
- A. always accompanies hyperglycemia.
- B. is the most prominent symptom of Cushing syndrome.
- C. is characteristic of chronic adrenal cortical insufficiency (Addison’s disease).
- D. is a consequence of ADH insufficiency.
Correct Answer: C
Rationale: Rationale: Bronzing is a characteristic symptom of chronic adrenal cortical insufficiency (Addison's disease) due to increased production of melanin. In this condition, the adrenal glands do not produce enough steroid hormones, leading to skin hyperpigmentation. This differs from hyperglycemia (choice A), Cushing syndrome (choice B), and ADH insufficiency (choice D), which do not directly cause bronzing. Therefore, the correct choice is C.
Which of the following is NOT a gland in the endocrine system?
- A. Adrenal gland
- B. Thyroid gland
- C. Kidney gland
- D. Pituitary gland
Correct Answer: C
Rationale: The correct answer is C: Kidney gland. The endocrine system consists of glands that secrete hormones directly into the bloodstream to regulate various bodily functions. The kidney is not a gland; it is an organ responsible for filtering waste from the blood and producing urine. The adrenal gland, thyroid gland, and pituitary gland are all part of the endocrine system as they secrete hormones. In summary, the kidney does not secrete hormones and therefore is not considered a gland in the endocrine system.
Most endocrine secretions are controlled by _____.
- A. positive feedback.
- B. negative feedback.
- C. neural feedback.
Correct Answer: B
Rationale: Step 1: Negative feedback is the primary mechanism in endocrine system regulation to maintain homeostasis.
Step 2: When hormone levels reach a certain set point, negative feedback signals the gland to stop producing that hormone.
Step 3: This ensures that hormone levels remain within a specific range.
Step 4: Positive feedback would lead to further hormone secretion, disrupting homeostasis.
Step 5: Neural feedback is not a common mechanism for regulating endocrine secretions.