ATI RN
Endocrine System Questions Questions
Question 1 of 5
A newly developed pesticide has been observed to bind to an intracellular hormone receptor. If ingested, residue from this pesticide could disrupt levels of
Correct Answer: B
Rationale: Intracellular hormone receptors, typically in the nucleus or cytoplasm, bind steroid or thyroid hormones, which cross membranes due to lipid solubility. Thyroid hormone (T3/T4) uses such receptors to regulate metabolism. Melatonin, growth hormone, and insulin act via membrane receptors, not intracellular ones. Pesticide binding could mimic or block thyroid hormone, disrupting metabolic balance, distinguishing it as the likely target, critical for endocrine disruption studies.
Question 2 of 5
The production of melatonin is inhibited by
Correct Answer: B
Rationale: Melatonin production by pinealocytes rises in darkness and is inhibited by bright light, detected by retinal-suprachiasmatic pathways, suppressing synthesis. Declining light boosts it, serotonin is a precursor (not inhibitor), and pinealocyte activity drives production. Light's inhibitory effect distinguishes melatonin regulation, key to sleep timing, contrasting with darkness-driven increase.
Question 3 of 5
Hormones produced by the thymus play a role in the
Correct Answer: A
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
Question 4 of 5
If an autoimmune disorder targets the alpha cells, production of which hormone would be directly affected?
Correct Answer: D
Rationale: Alpha cells in the pancreatic islets produce glucagon, raising blood glucose via glycogenolysis. An autoimmune attack on them directly reduces glucagon. Somatostatin, from delta cells, inhibits other hormones. Pancreatic polypeptide, from PP cells, regulates digestion. Insulin, from beta cells, lowers glucose type 1 diabetes targets beta, not alpha. Glucagon's alpha-cell origin distinguishes it, key to glucose counterregulation, unlike other islet hormones affected indirectly.
Question 5 of 5
Part of the effect of growth hormone is influenced by a group of protein chemical signals called:
Correct Answer: A
Rationale: Somatomedin-C (IGF-1), a liver-derived protein induced by growth hormone (GH), mediates GH's anabolic effects, promoting bone and muscle growth. Gonadotropins (FSH, LH) target gonads, not GH pathways. Prostaglandins regulate inflammation and smooth muscle, not growth. Prolactin drives lactation, not GH effects. Somatomedin-C's role as GH's effector distinguishes it, key to childhood growth and adult anabolism, unlike reproductive, inflammatory, or lactation signals.