In relation to noradrenaline, all of the following are true EXCEPT:
- A. It stimulates α and β receptors
- B. It decreases heart rate
- C. It decreases blood pressure
- D. Causes vasoconstriction
Correct Answer: C
Rationale: Rationale:
- Noradrenaline stimulates both α and β receptors, leading to increased heart rate and vasoconstriction.
- It does not decrease heart rate; it actually increases heart rate due to its actions on β receptors.
- Noradrenaline causes vasoconstriction by activating α receptors, leading to increased blood pressure.
- The incorrect statement is C, as noradrenaline actually increases blood pressure by causing vasoconstriction.
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Which drug is most likely to cause muscle tremor:
- A. Ipratropium
- B. Terbutaline
- C. Atenolol
- D. Nicotinic acid
Correct Answer: B
Rationale: The correct answer is B: Terbutaline. Terbutaline is a beta-2 adrenergic agonist used as a bronchodilator. It can stimulate beta-2 receptors in skeletal muscle, leading to muscle tremors as a common side effect. Ipratropium (A) is an anticholinergic bronchodilator and typically does not cause muscle tremors. Atenolol (C) is a beta-blocker and is not associated with muscle tremors. Nicotinic acid (D) is used to treat dyslipidemia and does not commonly cause muscle tremors. Therefore, Terbutaline is the most likely drug to cause muscle tremor among the options provided.
Identify a hormone that increases metabolic rate.
- A. thyroid hormone
- B. calcitonin
- C. aldosterone
- D. parathyroid hormone
Correct Answer: A
Rationale: The correct answer is A: thyroid hormone. The thyroid hormone plays a crucial role in regulating metabolism by increasing the body's metabolic rate. It accomplishes this by stimulating the production of proteins that control the rate at which cells use energy. Calcitonin (B) is involved in regulating calcium levels in the blood, not metabolic rate. Aldosterone (C) is a hormone that regulates electrolyte balance and blood pressure. Parathyroid hormone (D) regulates calcium and phosphorus levels in the blood, not metabolic rate. Thus, the correct choice is thyroid hormone as it directly affects metabolic rate.
The largest endocrine gland(s) that makes 3 hormones that affect the metabolism is the:
- A. pancreas
- B. adrenal glands
- C. thyroid gland
- D. pituitary gland
Correct Answer: C
Rationale: The correct answer is C: thyroid gland. The thyroid gland is the largest endocrine gland that produces 3 hormones (T3, T4, and calcitonin) that regulate metabolism. T3 and T4 control the body's metabolic rate, while calcitonin helps regulate calcium levels in the blood. The pancreas (A) primarily produces insulin and glucagon to regulate blood sugar levels. The adrenal glands (B) produce hormones like cortisol and adrenaline to regulate stress response. The pituitary gland (D) controls various other endocrine glands but does not primarily produce hormones affecting metabolism.
Which row identifies the chemical product of the fuel cell and the type of energy used to power the vehicles?
- A. hydrogen, electrical
- B. hydrogen, thermal
- C. water, electrical
- D. water, thermal
Correct Answer: C
Rationale: The correct answer is C because in a fuel cell, the chemical product is water (H2O) produced from the reaction of hydrogen and oxygen, and the energy used to power the vehicles is electrical energy generated from the electrochemical reaction in the fuel cell. Choice A (hydrogen, electrical) is incorrect because hydrogen is the input fuel, not the output product. Choice B (hydrogen, thermal) is incorrect because thermal energy is not the primary form of energy produced in a fuel cell. Choice D (water, thermal) is incorrect because while water is the product, the energy produced is electrical, not thermal.
This is a strange day for you in the emergency department. Now you have to treat another normovolemic patient with acute drug-induced hypotension, and give the usually correct and effective dose of phenylephrine. This time the drug causes a vasopressor response that is far greater than you've ever encountered: systolic pressure rises dramatically, if not dangerously. Which of the following drugs did the patient most likely take an overdose of?
- A. Atenolol
- B. Bethanechol
- C. Prazosin
- D. Reserpine
Correct Answer: D
Rationale: The correct answer is D: Reserpine. Reserpine is a drug that depletes catecholamines like norepinephrine and dopamine from nerve endings, leading to a prolonged and exaggerated response to sympathomimetic drugs like phenylephrine. This results in a dramatic increase in blood pressure when phenylephrine is given.
Rationale:
1. Atenolol (A) is a beta-blocker and would not lead to a vasopressor response.
2. Bethanechol (B) is a cholinergic agonist and would not lead to a vasopressor response.
3. Prazosin (C) is an alpha-1 adrenergic antagonist and would not lead to a vasopressor response.
In summary, Reserpine is the correct answer because it depletes catecholamines, leading to an exaggerated response to sympathomimetic drugs like phenylephrine, resulting in