The organ A which is located inside the skull of our body is protected by a bony box Band it is surrounded by three membranes C. The space between the membranes is filled with a liquid D which protects the organ A from mechanical shocks. The organ A in combination with another organ E makes up the central nervous system.

(a) What is organ A?


(b) What are (i) B (ii) C, and (iii) D ?


(c) Name the organ E.


(d) While walking barefooted, if we happen to step on a sharp piece of stone, we immediately lift our foot up. Which of the two organs, A or E, is directly involved in this action?


(e) If we step out from a darkened room into bright sunshine, we close our eyes for a moment. Which of the two organs, A or E, is directly involved in this action?

(a) In above question, the organ A is brain.

(b) (i) The membrane B is cranium or skull.


(ii) The membrane C is Meninges.


(iii) The membrane D is cerebrospinal fluid.


(c) The organ E is spinal cord.


(d) The organ E (spinal cord) is directly involved in the action mentioned in the question.


(e) The organ A (brain) is directly involved in the action mentioned in the question.


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