Nokea
Which of the following drugs is a direct stimulant of β1 and β2 adrenoceptors:
- A. Noradrenaline
- B. Isoprenaline
- C. Salbutamol
- D. Amphetamine
Correct Answer: B
Rationale: The correct answer is B: Isoprenaline. Isoprenaline directly stimulates both β1 and β2 adrenoceptors. It is a non-selective β-adrenergic agonist, leading to increased heart rate (β1 stimulation) and bronchodilation (β2 stimulation).
Incorrect choices:
A: Noradrenaline mainly acts on α-adrenoceptors.
C: Salbutamol is a selective β2 agonist, not stimulating β1 receptors.
D: Amphetamine primarily acts on catecholamine release and reuptake inhibition, not direct β-adrenoceptor stimulation.
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A nurse is teaching a client regarding a hormone that is released by beta islet cells in the pancreas. Which hormone is it?
- A. Progesterone
- B. Glucagon
- C. Insulin
- D. Parathormone
Correct Answer: C
Rationale: Insulin is released by beta cells in the pancreas and helps regulate blood sugar levels by promoting glucose uptake into cells.
What is the origin of accessory pancreatic duct?
- A. Distal part of dorsal pancreatic bud
- B. Proximal part of dorsal pancreatic bud
- C. The distal part of ventral pancreatic bud
- D. The proximal part of ventral pancreatic bud
Correct Answer: B
Rationale: The correct answer is B: Proximal part of dorsal pancreatic bud. The accessory pancreatic duct originates from the dorsal pancreatic bud during embryonic development. This is because the dorsal pancreatic bud gives rise to the body and tail of the pancreas, which includes the accessory pancreatic duct. The proximal part of the dorsal pancreatic bud specifically gives rise to the proximal part of the accessory pancreatic duct. Choices A, C, and D are incorrect because they refer to the distal part of the dorsal pancreatic bud, the distal part of the ventral pancreatic bud, and the proximal part of the ventral pancreatic bud, respectively, which are not associated with the origin of the accessory pancreatic duct.
Melatonin is secreted by which gland?
- A. Pineal gland
- B. Thyroid
- C. Thymus
- D. Adrenal
Correct Answer: A
Rationale: The correct answer is A: Pineal gland. Melatonin is a hormone that regulates sleep-wake cycles and is primarily secreted by the pineal gland located in the brain. The pineal gland responds to darkness by releasing melatonin, which helps to induce sleep. The other choices, B: Thyroid, C: Thymus, and D: Adrenal, do not secrete melatonin. The thyroid gland produces hormones that regulate metabolism, the thymus gland is involved in immune function, and the adrenal glands secrete hormones like cortisol and adrenaline. Therefore, the pineal gland is the correct answer for melatonin secretion.
The “melting of flesh into urine,†an old-timey name, is most descriptive of untreated:
- A. diabetes mellitus.
- B. Addison’s disease.
- C. diabetes insipidus.
- D. Cushing syndrome.
Correct Answer: A
Rationale: The correct answer is A: diabetes mellitus. This term describes the breakdown of body tissues for energy due to lack of insulin, leading to the production of ketones in the urine. In diabetes mellitus, the body cannot use glucose properly, causing the breakdown of fats and proteins. Addison's disease (B) involves adrenal insufficiency, not tissue breakdown. Diabetes insipidus (C) is a disorder of water balance, not tissue breakdown. Cushing syndrome (D) is characterized by excess cortisol production, not tissue breakdown into urine.
Hypocalcemic tetany:
- A. causes a flaccid paralysis.
- B. resembles neuromuscular blockade by curare.
- C. may be caused by a deficiency of PTH.
- D. is caused by a deficiency of insulin.
Correct Answer: C
Rationale: Step-by-step rationale:
1. Hypocalcemic tetany is associated with low levels of calcium in the blood.
2. Parathyroid hormone (PTH) plays a crucial role in calcium regulation.
3. A deficiency of PTH can lead to decreased calcium levels, causing tetany.
4. Therefore, choice C is correct as hypocalcemic tetany may be caused by a deficiency of PTH.
Summary:
A: Incorrect. Hypocalcemic tetany leads to muscle spasms, not flaccid paralysis.
B: Incorrect. Curare blockade affects neuromuscular transmission, not calcium levels.
D: Incorrect. Insulin deficiency is associated with hyperglycemia, not hypocalcemia leading to tetany.