Answer:
Stomata are small pores present on the surface of leaves and stem in plants. There are specialized cells named as gaurd cells which facilitates the opening and closing of stomatal pores. The two main functions of stomata are:
1. Gaseous exchange : It allows the uptake of carbon dioxide which is an important ingredient for conducting photosynthesis and release of oxygen to the external environment which is a product of photosynthesis.
2. Prevents the loss of water: Stomata remains closed during dry and warm external environmental conditions so as to prevent water loss.
In ordinary plants if stomata remains closed than there will be no gaseous exchange therefore, photosynthesis will not take place in these plants. Closed stomata will also prevent loss of water in dry and warm external conditions.