i) The part of brain which controls

A. voluntary action is cerebellum.

It controls and coordinates voluntary movements like body posture, balance, coordination, etc.

B. involuntary action is medulla.

It deals with autonomic functions of the body like breathing, heart rate etc.

ii) The peripheral nervous system is responsible for connecting the Central nervous system to the sensory and other organs of the body. Information is carried via the nerves of the PNS to and fro from the CNS to the organs.

The components of this nervous system are: the somatic nervous system and the autonomic nervous system and all the nerves lying outside the brain and spinal cord. The somatic nervous system is composed of nerves connecting the voluntary skeletal muscles to the sensory receptors of the body. The autonomic nervous systemhas the sympathetic and para-sympathetic nervous system responsible for regulating involuntary body functions.

The Autonomic Nervous Systemregulates the connections between the brain, spinal cord and organs, on the other hand, the Somatic Nervous System connects the external sensory organs through the brain and to the muscles.

iii) The glands that secrete:

• Insulin - Islets of Langerhans within the pancreatic gland.

• Thyroxin- Thyroid gland

The timing and amount of hormone secreted are regulated in human body. For example: Insulin is a secretion by the pancreas. It is responsible for maintaining the glucose level in the blood. If glucose level is high, more insulin is secreted and vice versa. Hormonal secretion is regulated by feedback mechanism. Another example is of parathyroid that secretes parathormone to raise the calcium level in the serum. When serum level gets high then negative feedback mechanism comes into play and signal is passed to decrease the secretion of the parathormone.