Blood levels of which of the following substances is decreased in Graves disease?
- A. Triiodothyronine (T3)
- B. Thyroxine (T4)
- C. Diiodotyrosine (DIT)
- D. Thyroid-stimulating hormone (TSH)
Correct Answer: D
Rationale: In Graves disease, there is an overproduction of thyroid hormones due to autoimmune stimulation. Thyroid-stimulating hormone (TSH) is decreased because the excessive thyroid hormones suppress its production through negative feedback. A and B are incorrect because both T3 and T4 levels are elevated in Graves disease. C is incorrect as DIT is a precursor to thyroid hormones and its levels may not necessarily be decreased in Graves disease.
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The bones, kidneys, and intestine are target organs of this calcium-regulator hormone.
- A. T3 and T4
- B. PTH
- C. ACTH
- D. Oxytocin
Correct Answer: B
Rationale: The correct answer is B: PTH. Parathyroid hormone (PTH) regulates calcium levels in the body by acting on bones, kidneys, and intestine. PTH stimulates release of calcium from bones, reabsorption of calcium in kidneys, and absorption of calcium in the intestine. T3 and T4 are thyroid hormones that do not directly regulate calcium levels. ACTH is adrenocorticotropic hormone that stimulates the adrenal glands. Oxytocin is a hormone involved in labor and lactation, not calcium regulation.
Which glands are responsible for the regulation of calcium levels in the blood?
- A. Parathyroid and thyroid
- B. Adrenal medulla and pancreas
- C. Testes
- D. Parathyroid and thymus
Correct Answer: A
Rationale: The correct answer is A: Parathyroid and thyroid. The parathyroid glands produce parathyroid hormone (PTH), which regulates calcium levels in the blood by increasing calcium absorption from the intestines and releasing calcium from bones. The thyroid gland produces calcitonin, which helps lower blood calcium levels by promoting calcium deposition in bones. The other choices (B: Adrenal medulla and pancreas, C: Testes, D: Parathyroid and thymus) are incorrect because they do not play a direct role in regulating calcium levels in the blood.
Mr. Olson, a 55-year-old, adult-onset, non-insulin-dependent diabetic is on a 1500 diabetic diet. He wants to have his nightly bourbon and water. The nurse should explain that
- A. each ounce of alcohol contains approximately 50 calories
- B. the bourbon should be mixed with 7-Up or ginger-ale rather than water
- C. the caloric content of the alcohol must be subtracted from the total diet prescription
- D. Fermented spirits (beer, wine) would be better if he insists on a nightly drink
Correct Answer: A
Rationale: Alcohol contains approximately 50 calories per ounce, and this must be considered in the patient's daily caloric intake.
Which of the following drugs selectively stimulates β2 adrenoceptors:
- A. Adrenaline
- B. Noradrenaline
- C. Isoprenaline
- D. Salbutamol
Correct Answer: D
Rationale: The correct answer is D: Salbutamol. Salbutamol is a selective β2 adrenoceptor agonist. It has a higher affinity for β2 receptors compared to β1 receptors, leading to bronchodilation without significant effects on the heart. A: Adrenaline and C: Isoprenaline stimulate both β1 and β2 receptors, causing increased heart rate and bronchodilation. B: Noradrenaline stimulates α1, α2, and β1 receptors, leading to vasoconstriction and increased heart rate. Therefore, salbutamol is the only drug that selectively stimulates β2 adrenoceptors, making it the correct choice.
The antagonistic hormone to aldosterone is ____.
- A. atrial natriuretic hormone (ANH).
- B. antidiuretic hormone (ADH).
- C. cortisol.
- D. glucagon.
Correct Answer: A
Rationale: The correct answer is A: atrial natriuretic hormone (ANH). ANH opposes the actions of aldosterone by promoting salt and water excretion, thus reducing blood volume and blood pressure. ANH is released in response to high blood pressure or high blood volume.
B: antidiuretic hormone (ADH) is not the antagonistic hormone to aldosterone; it acts on the kidneys to regulate water balance.
C: cortisol is a stress hormone and is not directly involved in regulating sodium and water balance.
D: glucagon is a hormone that increases blood sugar levels and is not related to the regulation of aldosterone.