Nokea
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.
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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.
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
ADH will stimulate _____ water reabsorption by the kidneys and ______ of the blood vessels; thus _____ blood pressure.
- A. decrease: constriction: increase
- B. decrease: dilation: decrease
- C. increase: constriction: increase
- D. increase: dilation: decrease
Correct Answer: C
Rationale: The correct answer is C because ADH (antidiuretic hormone) increases water reabsorption by the kidneys (increasing blood volume), causes vasoconstriction (narrowing of blood vessels), and ultimately leads to an increase in blood pressure. Choice A is incorrect because ADH does not decrease water reabsorption. Choice B is incorrect because ADH does not cause dilation of blood vessels, which would decrease blood pressure. Choice D is incorrect because ADH does not cause dilation of blood vessels, which would not lead to a decrease in blood pressure.
What is the speed of the wave?
- A. 1.5cm/s
- B. 3.0cm/s
- C. 300 cm/s
- D. 600 cm/s
Correct Answer: D
Rationale: The correct answer is D: 600 cm/s. The speed of a wave is determined by the formula speed = frequency x wavelength. Given that the frequency and wavelength are constant, the only way to increase the speed is to increase the frequency or the wavelength. Since both frequency and wavelength are fixed, the speed can only be increased by increasing both. Choice D, 600 cm/s, is double the speed of choice C, 300 cm/s, which indicates that both frequency and wavelength have been doubled, leading to the correct answer. Choices A and B are too low to be correct, as they are not consistent with the principles of wave speed calculation.
Oxytocin:
- A. is a neurohypophyseal hormone that stimulates the uterine muscle to contract, thereby assisting in labor.
- B. is a gonadotropin.
- C. stimulates the kidney to reabsorb Na+ and water, thereby expanding blood volume.
- D. is a mineralocorticoid.
Correct Answer: A
Rationale: Rationale:
1. Oxytocin is a neurohypophyseal hormone secreted by the posterior pituitary gland.
2. It plays a key role in stimulating uterine contractions during labor and childbirth.
3. This action helps in the progression of labor by promoting the expulsion of the fetus.
4. Oxytocin also stimulates milk ejection during breastfeeding.
5. Choice A is correct as it accurately describes the role of oxytocin in uterine muscle contraction.
Summary:
B: Oxytocin is not a gonadotropin; it does not directly affect gonadal function.
C: Oxytocin does not stimulate the kidney to reabsorb Na+ and water; that is the role of other hormones like aldosterone.
D: Oxytocin is not a mineralocorticoid; it does not regulate electrolyte balance like mineralocorticoids do.