What is Biosphere Reserve? Name any two Biosphere Reserves of India. Where are these Biosphere Reserves located?

Biosphere reserves are areas of terrestrial and coastal ecosystems which promote the conservation of biodiversity with its sustainable use. They are internationally recognized within the framework of UNESCO's.

i) Nilgiri Biosphere Reserve, in Tamil Nadu, Kerala, Karnataka
ii) Gulf of Mannar Biosphere Reserve, in Tamil Nadu