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Question #45727
The Question
A localized lesion selectively destroys the hypothalamo-hypophyseal tract in a patient, while the hypophyseal portal circulation remains completely intact. Which of the following represents the most accurate physiological outcome and its correct anatomical rationale?
Options
- A.
The pars nervosa loses its ability to synthesize vasopressin, leading to a failure of conditional water reabsorption in the distal convoluted tubule.
- B.
Vasopressin synthesis in the hypothalamus remains unaffected, but its axonal transport and release are blocked, leading to diuresis without glycosuria.
- C.
The transport of hypothalamic releasing hormones to the adenohypophysis is halted, causing a secondary failure of the adrenal cortex.
- D.
Osmoreceptors in the hypothalamus fail to detect changes in blood volume, causing continuous release of ADH from the posterior pituitary.
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
Neurohypophysis|Hypothalamus|Aquaporins
Why This Question Is Tricky
Common Mistakes
Location and Transport Trap: Students frequently confuse the synthetic site of posterior pituitary hormones (hypothalamus) with their storage site (pars nervosa), and confuse the neural connection (hypothalamo-hypophyseal tract) with the vascular connection (portal system).
This question tests the exact NCERT distinction between synthesis, axonal transport, and the clinical difference between Diabetes Insipidus (diuresis without glycosuria) and Diabetes Mellitus.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Excretory Products and Their Elimination - Class 11 |
| Concept | ADH (Vasopressin) Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |