Nokea
The following statements concerning prazosin and phentolamine are correct EXCEPT:
- A. Both antagonize alpha1-receptors
- B. Both cause the same degree of tachycardia
- C. Both decrease blood pressure
- D. Both are competitive antagonists
Correct Answer: B
Rationale: Correct Answer: B
Rationale:
1. Prazosin and phentolamine both antagonize alpha1-receptors, leading to vasodilation and decreased blood pressure.
2. Both drugs are competitive antagonists, competing with norepinephrine at alpha1-receptors.
3. However, phentolamine causes reflex tachycardia due to its non-selective alpha-adrenergic blockade, unlike prazosin.
4. Therefore, the statement that both cause the same degree of tachycardia is incorrect based on their pharmacological differences.
You may also like to solve these questions
Mrs. A., a 50-year-old female, has had symptoms of Cushing syndrome for several years. Mrs. A. states she is 5'5\ tall and weighs 160 lb but the nurse who measured and weighed Mrs. A. states she is only 5' tall. What is the best explanation for this discrepancy?"
- A. Mrs. A. is old and forgetful
- B. Mrs. A. has had previous back surgery
- C. The nurse has measured Mrs. A. incorrectly
- D. Osteoporosis and kyphosis have caused height loss
Correct Answer: D
Rationale: Osteoporosis and kyphosis are common in patients with Cushing syndrome, leading to a loss of height.
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.
You are preparing to review a teaching plan for a patient with type 2 diabetes. What will you check to determine the patient's level of compliance with his diabetic regimen?
- A. Patient's fasting glucose level
- B. Patient's oral glucose tolerance test results
- C. Patient's glycosylated hemoglobin assay
- D. Patient's fingerstick glucose check for 24 hours
Correct Answer: C
Rationale: The glycosylated hemoglobin assay (HbA1c) provides an average blood glucose level over the past 2-3 months and is the best indicator of long-term compliance with the diabetic regimen.
Which is a nutritionally essential amino acid?
- A. taunine
- B. leucine
- C. glutamate
- D. alanine
Correct Answer: B
Rationale: Rationale for correct answer (B - leucine): Leucine is an essential amino acid, meaning it cannot be synthesized by the body and must be obtained through diet. It plays a crucial role in protein synthesis, muscle repair, and growth. It is essential for overall health and well-being.
Summary of why other choices are incorrect:
A - taurine: Taurine is a conditionally essential amino acid, not nutritionally essential.
C - glutamate: Glutamate is a non-essential amino acid, as the body can synthesize it.
D - alanine: Alanine is a non-essential amino acid, as the body can also produce it.
Steroid hormones _____________________.
- A. bind to a receptor inside the target cell
- B. are made from cholesterol
- C. cause the cell to make new proteins
- D. all of these
Correct Answer: D
Rationale: The correct answer is D because steroid hormones bind to a receptor inside the target cell, are made from cholesterol, and cause the cell to make new proteins. This is known as the mechanism of steroid hormone action. Choice A is correct as steroid hormones need to bind to intracellular receptors to exert their effects. Choice B is also correct as steroid hormones are derived from cholesterol. Choice C is correct as one of the main actions of steroid hormones is to regulate gene expression and induce the synthesis of new proteins within the cell. Therefore, all of these statements are true regarding steroid hormones, making choice D the correct answer.