Nokea
The secretion of cortisol by the adrenal gland suppresses further secretion of ACTH by the anterior pituitary gland. What is this interaction called?
- A. Cerebral lateralization
- B. Circadian rhythm
- C. Cellular differentiation
- D. Negative feedback control
Correct Answer: D
Rationale: The correct answer is D: Negative feedback control. This interaction is a classic example of negative feedback control in the endocrine system. Cortisol inhibits the release of ACTH, which in turn reduces the stimulation of cortisol production, creating a feedback loop to maintain hormonal balance. Choice A, cerebral lateralization, refers to the specialization of brain function. Choice B, circadian rhythm, pertains to the 24-hour biological cycle. Choice C, cellular differentiation, involves the process of cells becoming specialized for specific functions. Thus, the correct answer is D because it accurately describes the feedback mechanism at play in the cortisol-ACTH interaction.
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Thyroxine:
- A. is mostly bound to albumin in the plasma, since this has the largest capacity
- B. is 2-5 times more potent that triiodothyronine (T3)
- C. stimulates TSH release
- D. ∼33% is deiodinated in the liver to T3
Correct Answer: D
Rationale: The correct answer is D. Thyroxine is deiodinated in the liver to T3, so approximately 33% of thyroxine is converted to the more active form, triiodothyronine. This conversion is important for regulating metabolic processes in the body. Choices A and C are incorrect because thyroxine is primarily bound to thyroxine-binding globulin in the plasma, not albumin, and it does not stimulate TSH release. Choice B is incorrect because T3 is actually more potent than thyroxine, not the other way around.
Since Adonis was unable lift the dumbbell, he decided to use the exercise bike for a cardiovascular workout. During maximum exertion on the exercise bike, Adonis began to breathe heavily and felt 'the burn' in his legs. The skeletal muscles of his legs were using primarily which form of respiration at maximum exertion?
- A. Aerobic respiration
- B. Electron transport chain
- C. Oxidative phosphorylation
- D. Glycolysis
Correct Answer: d
Rationale: The correct answer is D: Glycolysis. During maximum exertion, skeletal muscles rely on glycolysis to quickly generate ATP without oxygen. This process breaks down glucose into pyruvate, producing a small amount of ATP. Since Adonis was feeling 'the burn' in his legs, it indicates the accumulation of lactic acid from glycolysis. Choice A (Aerobic respiration) requires oxygen and is not efficient during high-intensity exercise. Choices B (Electron transport chain) and C (Oxidative phosphorylation) are part of aerobic respiration and occur in mitochondria, which are less active during intense exercise compared to glycolysis.
Which of the following evidences anticholinergic side effects:
- A. Excessive salivation
- B. Bradycardia
- C. Diarrhea and colic
- D. Tachycardia
Correct Answer: D
Rationale: The correct answer is D: Tachycardia. Anticholinergic medications block the action of acetylcholine, leading to increased heart rate (tachycardia) by inhibiting the parasympathetic nervous system. Excessive salivation (choice A) is a cholinergic effect, not anticholinergic. Bradycardia (choice B) is not consistent with anticholinergic side effects. Diarrhea and colic (choice C) are more commonly associated with cholinergic, not anticholinergic, effects.
A 35-year-old female presents to your office for a regular check-up. Her only complaint is recurrent migraine headaches, which have increased in frequency over the years. On examination, her blood pressure is elevated at 150/70. You decide to start her on antihypertensive therapy that is also used for prophylaxis of migraines. Which medication is it?
- A. Clonidine
- B. Prazosin
- C. Hydrochlorothiazide
- D. Propranolol
Correct Answer: D
Rationale: The correct answer is D: Propranolol. Propranolol is a beta-blocker that is commonly used for migraine prophylaxis. It helps reduce the frequency and severity of migraines by blocking the action of adrenaline on blood vessels in the brain. In this case, the patient has elevated blood pressure and migraines, so starting her on propranolol can address both issues effectively.
Choice A: Clonidine is an alpha-2 agonist used for hypertension, but it is not commonly used for migraine prophylaxis.
Choice B: Prazosin is an alpha-1 blocker primarily used for the treatment of hypertension, but it is not typically used for migraine prophylaxis.
Choice C: Hydrochlorothiazide is a diuretic used for hypertension by reducing blood volume, but it is not effective for migraine prophylaxis.
In summary, propranolol is the most appropriate choice as it addresses both the elevated blood pressure and the recurrent
The nurse is assessing a client who exhibits spontaneous spasm of the fingers or toes, mouth twitching or jaw tightening when he taps the cheek anteriorly to the earlobe. What sign does the nurse identify to document in the chart that is consistent with tetany?
- A. Lhermitte's sign
- B. Trousseau's sign
- C. Chvostek's sign
- D. Bulge sign
Correct Answer: C
Rationale: Chvostek's sign is a positive sign of tetany, where tapping the cheek causes twitching of the facial muscles, indicating low calcium levels.