(a) Brain is covered by a three layered membrane called meninges. In between the layers of meninges and brain, cavity fluid named Cerebro Spinal Fluid (CSF) is filled. The hard skull covers the meninges. Thus Meninges, CSF and Skull protects our brain for a certain extent.

(b) Two main parts of hind-brain are

Medulla and Cerebellum.

Their functions are:

Medulla : Involuntary actions such as blood pressure, salivation and vomiting.

Cerebellum : It is responsible for precision of voluntary actions and maintaining the posture and balance of the body.