Nokea
Which of the following hormones exerts negative feedback control on the secretion of ACTH?
- A. PTH
- B. Glucagon
- C. Cortisol
- D. Corticotrophin-releasing hormone
Correct Answer: C
Rationale: The correct answer is C: Cortisol. Cortisol exerts negative feedback control on the secretion of ACTH by inhibiting the release of corticotrophin-releasing hormone (CRH) and ACTH from the hypothalamus and pituitary gland, respectively. This feedback loop helps regulate the body's stress response and maintain hormone levels within a normal range.
A: PTH (Parathyroid Hormone) does not directly regulate the secretion of ACTH.
B: Glucagon regulates blood sugar levels and does not directly affect ACTH secretion.
D: Corticotrophin-releasing hormone (CRH) is the hormone that stimulates the release of ACTH, so it does not exert negative feedback control on ACTH secretion.
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In the emergency department, during initial assessment of a new admission with diabetes, you discover all of the following. Which information should you immediately report to the physician?
- A. Hammertoe of the left second metatarsophalangeal joint
- B. Rapid respiratory rate with deep inspirations
- C. Numbness and tingling bilaterally in feet and hands
- D. Decreased sensitivity and swelling of the abdomen
Correct Answer: B
Rationale: Rapid respiratory rate with deep inspirations may indicate diabetic ketoacidosis (DKA) or another metabolic disturbance and requires immediate intervention.
The secretion of parathyroid hormone is a good example of __________.
- A. pituitary gland stimuli
- B. humoral stimuli
- C. neural stimuli
- D. hormonal stimuli
Correct Answer: B
Rationale: The correct answer is B: humoral stimuli. Parathyroid hormone secretion is regulated by the concentration of calcium in the blood, which is an example of humoral stimuli. When blood calcium levels decrease, parathyroid hormone is released to increase calcium levels. Pituitary gland stimuli (A), neural stimuli (C), and hormonal stimuli (D) are not directly involved in the regulation of parathyroid hormone secretion.
Atropine has the following pharmacological effects EXCEPT:
- A. It increases the heart rate
- B. Stimulates the respiratory center
- C. Has a mydriatic effect
- D. Produces bronchoconstriction
Correct Answer: D
Rationale: The correct answer is D: Atropine does not produce bronchoconstriction. Atropine is an anticholinergic drug that blocks the action of acetylcholine, leading to increased heart rate (A), stimulation of the respiratory center (B), and mydriatic effect (C). Bronchoconstriction is not a pharmacological effect of atropine because it actually helps dilate the bronchi, making it a useful treatment in cases of bronchospasm.
Which gland is associated with “sugar, salt, and sex�
- A. Adrenal cortex
- B. Pancreas
- C. Parathyroid gland
- D. Neurohypophysis
Correct Answer: A
Rationale: The correct answer is A: Adrenal cortex. The adrenal cortex is associated with producing hormones related to sugar (glucocorticoids), salt (mineralocorticoids), and sex (androgens). Glucocorticoids regulate glucose metabolism, mineralocorticoids regulate salt balance, and androgens are sex hormones. The pancreas primarily regulates blood sugar levels. The parathyroid gland is responsible for calcium and phosphorus balance, not sugar, salt, and sex. The neurohypophysis is part of the pituitary gland and mainly regulates water balance and blood pressure, not specifically sugar, salt, and sex.
Which of the following explains the suppression of lactation during pregnancy?
- A. Blood prolactin levels are too low for milk production to occur
- B. Human placental lactogen levels are too low for milk production to occur
- C. The fetal adrenal gland does not produce sufficient estriol
- D. Blood levels of estrogen and progesterone are high
Correct Answer: D
Rationale: The correct answer is D. During pregnancy, high levels of estrogen and progesterone inhibit lactation by suppressing the release of prolactin, the hormone responsible for milk production. Estrogen and progesterone maintain the pregnancy and prevent premature labor, so the body prioritizes their functions over lactation. Choices A, B, and C are incorrect because low blood prolactin levels, human placental lactogen levels, and fetal adrenal gland's estriol production are not directly related to the suppression of lactation during pregnancy.