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

Which of the following statements are true about the brain?
$(i)$ The main thinking part of the brain is the hindbrain.
$(ii)$ Centres of hearing,smell,memory,sight,etc.,are located in the forebrain.
$(iii)$ Involuntary actions like salivation,vomiting,and blood pressure are controlled by the medulla in the hindbrain.
$(iv)$ Cerebellum does not control posture and balance of the body.

Define 'reflex action'.

Which is the main thinking part of the brain? State how it functions.

How many pairs of spinal nerves arise from the human spinal cord?

Which of the following statements is correct about receptors?