From which part of brain cerebrospinal fluid is secreted?

Appeared in: UPPSC 2017

Explanation

The choroid plexus, a network of capillaries and specialized ependymal cells located in the brain's ventricles, is the primary site for cerebrospinal fluid (CSF) production.
These specialized tissues actively secrete CSF into the lateral, third, and fourth ventricles.
The rate of CSF production is approximately 500 mL per day, with the total volume in the system being maintained at around 150 mL in an adult.

Option B: The venous sinuses, particularly the superior sagittal sinus, are the primary sites for CSF absorption back into the bloodstream via arachnoid villi, not secretion.
Option C: The subarachnoid space is where CSF circulates after it exits the ventricles. It provides a protective cushion for the brain and spinal cord but does not produce the fluid.
Option D: This option is incorrect because a correct answer, the choroid plexus, is listed as an option.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Secretion and circulation of Cerebrospinal Fluid (CSF) as background academic context rather than a clinical decision trigger.
Understanding CSF circulation is crucial for nurses when caring for patients with conditions like hydrocephalus (CSF buildup), meningitis (inflammation), or those undergoing a lumbar puncture (spinal tap) to analyze CSF.
Nurses monitor for signs of increased intracranial pressure (e.g., headache, vomiting, altered consciousness), which can result from abnormal CSF pressure or composition, indicating serious neurological disorders.
What if? If the arachnoid villi were blocked (e.g., by infection or hemorrhage), CSF absorption would be impaired. This would lead to communicating hydrocephalus, where CSF can still flow between ventricles but cannot be effectively drained, causing pressure to build up in the brain.

How to Approach the Question

Identify the keywords in the question: 'cerebrospinal fluid' and 'secreted'.
The question asks for the origin or production site of CSF.
Recall the key structures of the CSF system: ventricles, choroid plexus, subarachnoid space, and arachnoid villi/venous sinuses.
Evaluate the function of each option: Choroid plexus (production), Venous sinus (absorption), Subarachnoid space (circulation).
Select the option that correctly identifies the site of secretion/production.
Eliminate the options related to absorption and circulation to confirm the correct answer.

Concept Tested & Keywords

QDtFB0NcyOGWEQ2aM2HFfj

E6 Anatomy Grays 43e Vol 1 Part 3 p. 45-47

E6 Nelson Textbook of Pediatrics(2024) — Volume 2 p. 1383-1385

Practise the full UPPSC 2017

Attempt every question from this paper in a timed mock, then review the full solution for each one.