___________________Outer bony covering that protects the gills.

Q. Which of the following is a bony cover box in the skull that protects the brain?

Q. Both the crown and root of a tooth is covered by a layer of a bony hard substance called:

Q. The organ A which is located inside the skull of our body is protected by a bony box B and 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?

Q. The organ A which is located inside the skull of our body is protected by a bony box B and 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. ​

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