$(a)$ If the cerebellum is not functioning properly,what are the activities of our body affected?
$(b)$ How do muscle cells move?

'Brain and spinal cord are two vital organs of our body'. How is our body designed to protect them?

What is cerebrospinal fluid? What is its function?

Mention any four reflex actions of the body.

Which system facilitates the communication between the central nervous system and other parts of the body?

Which of the following statements are true?
$(i)$ Sudden action in response to something in the environment is called reflex action.
$(ii)$ Sensory neurons carry signals from spinal cord to muscles.
$(iii)$ Motor neurons carry signals from receptors to spinal cord.
$(iv)$ The path through which signals are transmitted from a receptor to a muscle or a gland is called reflex arc.