Nokea
Which one of the following is NOT typical of the changes that follow the binding of a hormone to its target cells:
- A. plasma membrane permeability changes
- B. cellular mutations occur
- C. enzymes are activated or inactivated
- D. mitosis is stimulated
Correct Answer: B
Rationale: The correct answer is B: cellular mutations occur. Hormone binding typically triggers signaling cascades that lead to cellular responses like changing plasma membrane permeability, activating/inactivating enzymes, or stimulating mitosis. Cellular mutations are not a direct result of hormone binding and are typically caused by external factors like radiation or chemicals. In this context, mutations do not happen as an immediate response to hormone binding. Therefore, option B is the correct choice. Plasma membrane permeability changes, enzyme activation/inactivation, and mitosis stimulation are all typical outcomes of hormone binding and subsequent signaling pathways.
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What is the most likely effect of a deficiency of aldosterone?
- A. High blood pressure
- B. Low level of potassium in the blood
- C. Low blood volume and hypotension
- D. Goiter formation
Correct Answer: C
Rationale: Rationale:
1. Aldosterone regulates sodium and water balance in the body.
2. Deficiency leads to decreased sodium reabsorption, causing low blood volume.
3. Low blood volume results in hypotension due to reduced blood flow to tissues.
4. Choices A and B are incorrect as aldosterone deficiency does not cause high blood pressure or low potassium levels.
5. Choice D is incorrect as goiter formation is mainly related to thyroid hormone imbalance, not aldosterone deficiency.
We want to prescribe scopolamine, as a transdermal drug delivery system (skin patch), for a patient who will be leaving for an expensive cruise and is very susceptible to motion sickness. For which of the following co-morbidities is scopolamine contraindicated?
- A. Angle-closure (narrow-angle) glaucoma
- B. Bradycardia
- C. History of shellfish allergies
- D. Resting blood pressure of 112/70
Correct Answer: A
Rationale: The correct answer is A: Angle-closure (narrow-angle) glaucoma. Scopolamine, an anticholinergic medication, can worsen angle-closure glaucoma by causing pupil dilation leading to increased intraocular pressure. This can result in a sudden and severe increase in eye pressure, leading to potential vision loss. Therefore, it is contraindicated in patients with narrow-angle glaucoma.
B: Bradycardia is not a contraindication for scopolamine use as it may actually help in treating motion sickness.
C: History of shellfish allergies is not a contraindication for scopolamine as the medication is not derived from shellfish and is safe for patients with this allergy.
D: Resting blood pressure of 112/70 is not a contraindication for scopolamine use as it falls within the normal range and should not pose any significant risk.
Simple goiter can be prevented by _________.
- A. antibiotics
- B. adding iodine to the diet
- C. surgery
- D. hormone therapy
Correct Answer: B
Rationale: The correct answer is B: adding iodine to the diet. Iodine deficiency is a common cause of simple goiter. Iodine is essential for the production of thyroid hormones, and a lack of it can lead to the enlargement of the thyroid gland. Adding iodine to the diet helps prevent simple goiter by ensuring the thyroid has enough iodine to function properly. Antibiotics (choice A) are not effective for preventing goiter as it is not caused by bacteria. Surgery (choice C) and hormone therapy (choice D) are typically used to treat goiter once it has developed, not prevent it.
A 46-year-old woman has hirsutism, hyperglycemia, obesity, muscle wasting, and increased ACTH. The most likely cause of her symptoms is
- A. primary adrenocortical insufficiency (Addison disease)
- B. pheochromocytoma
- C. primary overproduction of ACTH (Cushing disease)
- D. treatment with exogenous glucocorticoids
Correct Answer: C
Rationale: The correct answer is C: primary overproduction of ACTH (Cushing disease). In this case, the symptoms match those of Cushing syndrome, which is characterized by excess cortisol production. The increased ACTH levels are indicative of the pituitary gland overproducing ACTH, leading to excess cortisol. Choices A and B are incorrect as they do not match the symptoms presented. Choice D is incorrect because exogenous glucocorticoids would not lead to increased ACTH levels.
Mrs. Klein, aged 35 years, has just been diagnosed as diabetic. She is being put on a 1200 calorie diabetic diet with 50% of the calories to be from carbohydrates, 20% from protein, and 30% from fat. In instructing her about her diet, which of the following would be the best breakfast to suggest?
- A. Three waffles with butter, dietetic syrup, coffee
- B. One boiled egg, corn flakes with one glass milk, coffee, glass of orange juice
- C. A cheese omelet (4 oz cheddar, three eggs), one slice toast, one glass milk
- D. Two buttered English muffins, glass of grapefruit juice, coffee
Correct Answer: C
Rationale: A cheese omelet with protein and appropriate carbohydrate content fits the macronutrient distribution for a diabetic diet.