Question

name the gases utilised and liberated in photosynthesis

Answer 1

The gasses utilised and liberated in photosynthesis are nitrogen, oxygen and carbon dioxide .
The plants obtain Carbon dioxide directly from the atmosphere and liberates oxygen to the atmosphere through the stomata.
But, it obtains nitrogen mainly by three other factors as the atmospheric nitrogen isn't useful to plant and the plants can't take it easily. Three factors are :
i) Nitrogen fixation by leguminous crops with the help of rhizobium bacteria. ii) Nitrogen provided by the Fertilisers.
iii) Nitrogen fixation in the soil due to lightning and thunder.
IN all the above 3 cases, the nitrogen is either IN the form of nitrates or nitrites as Nitrogen dioxide gas is of no use to the plants directly.