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Question #46846
The Question
During the regulation of the anterior pituitary, hypothalamic releasing hormones bind to membrane-bound receptors to stimulate secretion. If a specific pharmacological agent inhibits the generation of the second messenger IP3 (Inositol triphosphate) in these target cells, which of the following will be the most direct and immediate consequence?
Options
- A.
The hypothalamic hormones will enter the pituitary cells but fail to form an active hormone-receptor complex at the nucleus.
- B.
The failure to elevate intracellular Ca2+ levels will prevent the docking and exocytosis of vesicles containing stored pituitary hormones.
- C.
The anterior pituitary cells will immediately cease the transcription of mRNA for trophic hormones due to the absence of cAMP.
- D.
The membrane-bound receptors will undergo conformational changes, but the hormone will be unable to diffuse across the lipid bilayer.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Glandular Secretion Mechanism|Secondary Messenger Cascade|Hormonal Feedback
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the list of second messengers (cAMP, IP3, Ca2+) without linking them to their specific cellular functions.
The trap relies on distinguishing between the immediate secretory response (calcium-mediated exocytosis) and long-term genomic responses (transcription), while also filtering out distractors that describe steroid hormone mechanisms.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Structural Organisation in Animals - Class 11 |
| Concept | Glandular Secretion Mechanism |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |