What is the primary role of the hypothalamic-pituitary-adrenal (HPA) axis?
To manage calcium levels in the blood.
To control blood glucose levels through insulin secretion.
To regulate thyroid hormone levels.
To regulate stress response via hormone secretion.
The Correct Answer is D
A. To manage calcium levels in the blood: The HPA axis primarily deals with stress hormones (CRH → ACTH → cortisol) rather than direct regulation of calcium homeostasis, which is managed mainly by the parathyroid hormone and vitamin D.
B. To control blood glucose levels through insulin secretion: Insulin secretion is controlled by the pancreas; the HPA axis influences glucose metabolism indirectly via cortisol but does not control insulin release.
C. To regulate thyroid hormone levels: Thyroid regulation is principally the hypothalamic–pituitary–thyroid axis (TRH → TSH → thyroid hormones), not the HPA axis.
D. To regulate stress response via hormone secretion: The HPA axis initiates and coordinates the hormonal stress response by releasing CRH from the hypothalamus, ACTH from the pituitary, and cortisol from the adrenal cortex, which mobilizes energy and modulates many systems during stress.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is D
Explanation
A. Thyroid-stimulating hormone (TSH):TSH is released by the anterior pituitary in response to thyrotropin-releasing hormone (TRH) from the hypothalamus, not CRH.
B. Prolactin:Prolactin release is primarily inhibited by dopamine and can be stimulated by TRH and other factors, but it is not the principal anterior pituitary response to CRH.
C. Growth hormone (GH):GH secretion is regulated mainly by growth hormone–releasing hormone (GHRH) and somatostatin from the hypothalamus, not by CRH.
D. Adrenocorticotropic hormone (ACTH):ACTH is secreted by the anterior pituitary in response to corticotropin-releasing hormone (CRH) from the hypothalamus and stimulates the adrenal cortex to produce cortisol.
Correct Answer is C
Explanation
A. Negative feedback on the thyroid gland:Cushing's disease involves cortisol dysregulation and does not primarily disrupt negative feedback of the thyroid axis.
B. Positive feedback on the pituitary gland:Pituitary-driven Cushing's involves excess ACTH but the disrupted mechanism is not a physiological positive feedback loop on the pituitary.
C. Negative feedback on the hypothalamus and pituitary:Elevated cortisol should suppress CRH and ACTH via negative feedback; in Cushing's disease this feedback loop is impaired because a pituitary adenoma continues to produce ACTH despite high cortisol.
D. Positive feedback on the adrenal cortex:The adrenal cortex responds to ACTH but physiological regulation of cortisol does not operate via positive feedback on the cortex.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.