ATI RN
Endocrine System Exam Questions Questions
Question 1 of 5
The neurotransmitter released at the end of most sympathetic nerve fibers is:
Correct Answer: B
Rationale: The correct answer is B: Noradrenaline. Sympathetic nerve fibers release noradrenaline as the primary neurotransmitter to activate the fight-or-flight response. Noradrenaline acts on adrenergic receptors to increase heart rate, blood pressure, and blood flow to muscles. Epinephrine (choice A) is also released in the sympathetic nervous system but mainly by the adrenal glands. Acetylcholine (choice C) is the primary neurotransmitter in the parasympathetic nervous system. Acetylcholinesterase (choice D) is an enzyme that breaks down acetylcholine and is not a neurotransmitter.
Question 2 of 5
Neostigmine is a drug useful in the treatment of myasthenia gravis, but it causes parasympathomimetic effects unless another drug is given first. This drug is:
Correct Answer: A
Rationale: The correct answer is A: Atropine. Neostigmine is a cholinesterase inhibitor that increases acetylcholine levels leading to parasympathomimetic effects. Atropine, an anticholinergic drug, blocks the effects of acetylcholine, preventing excessive stimulation of cholinergic receptors. Administering atropine before neostigmine helps counteract the parasympathomimetic effects, making it a necessary pre-treatment. Epinephrine and isoproterenol are adrenergic drugs and wouldn't counteract the cholinergic effects of neostigmine. Edrophonium is another cholinesterase inhibitor like neostigmine, so it wouldn't be effective in preventing the parasympathomimetic effects.
Question 3 of 5
Which of the following occur due to increased secretion of testosterone during puberty in male humans?
Correct Answer: A
Rationale: 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.
Question 4 of 5
Which row shows the correct order of reactivity for the elements?
Correct Answer: D
Rationale: The correct order of reactivity for elements is based on their tendency to lose electrons. In this case, sodium is the most reactive as it readily loses an electron to form a stable ion. Zinc is less reactive compared to sodium but more reactive than hydrogen and gold. Hydrogen is less reactive than both zinc and sodium. Gold is the least reactive among the options given. Therefore, the correct order of reactivity is sodium > zinc > hydrogen > gold, which matches option D. Choices A, B, and C do not follow the correct order of reactivity for the elements listed, making them incorrect.
Question 5 of 5
Which row gives the relative charges of electrons and neutrons?
Correct Answer: C
Rationale: The correct answer is C: -1, 0. Electrons have a charge of -1, while neutrons have no charge (0). This is because electrons are negatively charged particles, while neutrons are neutral. The other choices are incorrect because A: 0, 0 doesn't differentiate between the charges of electrons and neutrons, B: 0, -1 incorrectly assigns a charge to neutrons, and D: -1, +1 incorrectly assigns a charge to neutrons and doesn't represent the relative charges accurately.