RN exams endocrine practice questions set 4

Correct answer:

Step-by-step rationale for why choice A is correct: 1. The adrenal cortex is indeed the target gland of ACTH (Adrenocorticotropic hormone). 2. ACTH stimulates the adrenal cortex to produce and release corticosteroid hormones. 3. These corticosteroid hormones play crucial roles in regulating metabolism, immune response, and stress response. 4. Therefore, choice A accurately describes the relationship between the adrenal cortex and ACTH. Summary: Choice A is correct because the adrenal cortex is the target gland of ACTH, not the other choices. The adrenal medulla secretes catecholamines (choice B), hormones that raise blood glucose (not lower, as in choice C), and iodine-containing hormones are secreted by the thyroid gland, not the adrenal cortex (choice D).

Correct answer:

The correct answer is B: Hypothalamus. The hypothalamus controls the pituitary gland by releasing hormones that stimulate or inhibit pituitary hormone production. This relationship is known as the hypothalamic-pituitary axis. The hypothalamus is considered the master controller of the endocrine system, making it the correct choice. A: Thyroid - The thyroid gland is not directly responsible for controlling the pituitary gland. It is a separate endocrine gland that produces its own hormones. C: Pineal gland - The pineal gland primarily regulates the sleep-wake cycle and produces melatonin. It does not play a direct role in controlling the pituitary gland. D: None of the above - This is incorrect as the hypothalamus does indeed control the pituitary gland.

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The correct answer is C: An amino acid derivative can be a hormone. This statement is correct because many hormones are derived from amino acids, such as thyroid hormones (derived from tyrosine) and epinephrine (derived from phenylalanine). Hormones can be derived from various sources, including amino acids, peptides, lipids, and even gases. Explanation of other choices: A: Prostaglandins are not biologically active peptides; they are lipid compounds derived from fatty acids. B: Modified cholesterol does not form the main structural component of peptone hormones; peptides are the main structural components of peptide hormones. D: Testosterone is a steroid hormone and not an example of a paracrine, which is a type of chemical messenger that acts on nearby cells.

Correct answer:

Step 1: Increased muscle growth (1) is due to testosterone promoting protein synthesis, leading to muscle hypertrophy. Step 2: Deepening of voice (2) is caused by testosterone thickening the vocal cords. Step 3: Growth of facial hair (3) is stimulated by testosterone promoting hair follicle growth. Step 4: Enlargement of testes (4) is a direct effect of increased testosterone levels. Therefore, choices A, B, C, and D are analyzed: - B is incorrect as it excludes the enlargement of testes. - C is incorrect as it excludes the growth of facial hair. - D is incorrect as it excludes both muscle growth and the growth of facial hair. Conclusion: Choice A is correct as it includes all the effects of increased testosterone secretion during puberty in male humans.

Correct answer:

Step 1: Albuterol selectively activates β2 adrenergic receptors in low doses. Step 2: Isoprenaline is a non-selective beta-adrenergic agonist. Step 3: Very large doses of albuterol or IV administration would lead to non-selective activation of beta receptors. Step 4: Isoprenaline also activates both β1 and β2 receptors, causing a broad range of effects. Step 5: Therefore, the effects of high-dose albuterol would resemble those of Isoprenaline, making B the correct answer. Summary: Choice A (Epinephrine) is incorrect because epinephrine primarily acts on both α and β adrenergic receptors, not just β2. Choice C (Norepinephrine) is incorrect as it mainly acts on α adrenergic receptors, not β. Choice D (Phenylephrine) is incorrect because it is a

Correct answer:

The correct answer is A: nervous system. The nervous system can directly override normal endocrine controls through the release of neurotransmitters that can stimulate or inhibit hormone release from endocrine glands. The nervous system can rapidly respond to immediate changes in the internal or external environment, allowing for quick adjustments in hormone levels. Summary of why the other choices are incorrect: B: The circulatory system is not involved in directly overriding endocrine controls. C: The digestive system primarily regulates the breakdown and absorption of nutrients, not endocrine controls. D: The reproductive system is responsible for the production of sex hormones and gametes, but it does not directly override normal endocrine controls.

Correct answer:

The correct answer is A because the posterior pituitary gland is an extension of the hypothalamus. The hypothalamus produces hormones that are stored and released by the posterior pituitary gland. This connection between the two structures allows for direct neural control over hormone release. Option B is incorrect because the neurohypophysis does not secrete releasing hormones; rather, it releases hormones produced by the hypothalamus. Option C is incorrect because the posterior pituitary gland does not regulate adenohypophyseal function; instead, it stores and releases hormones produced by the hypothalamus. Option D is incorrect because the posterior pituitary gland does not secrete releasing hormones; it releases hormones produced by the hypothalamus.

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Centripetal obesity, acne, and hirsutism are classic features of Cushing's syndrome. Cushing's syndrome results from prolonged exposure to high levels of cortisol, which can be due to various causes such as adrenal tumors, pituitary adenomas, or exogenous glucocorticoid use. Centripetal obesity refers to the characteristic fat distribution pattern seen in Cushing's syndrome, where fat accumulates mainly in the face, neck, and trunk while sparing the limbs. Acne and hirsutism are also commonly seen in Cushing's syndrome due to the hormonal imbalances caused by excess cortisol. Testing for serum cortisol levels, dexamethasone suppression tests, and imaging studies can help confirm the diagnosis of Cushing's syndrome in a patient presenting with these symptoms.

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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

Correct answer:

Step-by-step rationale for why choice A is correct: 1. The adrenal cortex is indeed the target gland of ACTH (Adrenocorticotropic hormone). 2. ACTH stimulates the adrenal cortex to produce and release corticosteroid hormones. 3. These corticosteroid hormones play crucial roles in regulating metabolism, immune response, and stress response. 4. Therefore, choice A accurately describes the relationship between the adrenal cortex and ACTH. Summary: Choice A is correct because the adrenal cortex is the target gland of ACTH, not the other choices. The adrenal medulla secretes catecholamines (choice B), hormones that raise blood glucose (not lower, as in choice C), and iodine-containing hormones are secreted by the thyroid gland, not the adrenal cortex (choice D).