In which organ and site do photosynthesis in green plants? Mention the raw material required for this process. how are they obtained? What is the chemical process and by-products obtained in photosynthesis? Explain with the help of a chemical equation.

                                                       (OR)

(i) Sketch the cross-section of a leaf and label the following parts:

(a) Chloroplast              (b) Cuticle.

(ii)  What type of gas evolved during photosynthesis? Also mention the way in which the gas evolved.

(iii)  Some plant's stomata remain closed throughout the day. How do these plants prepare food? Also, give the name of such a plant.

(i)  Photosynthesis occurs in green plants' grana and stroma of the chloroplast.

(ii)  The raw materials required for this process are carbon dioxide and water in the presence of sunlight and chlorophyll.

(iii)  Carbon dioxide enters the leaves through stomata, and cells of the roots absorb water from the soil.

(iv) Balanced equation for photosynthesis 

                                                   (OR)

(ii)  Oxygen gas is released during photosynthesis. The splitting of water evolves this gas.

2$H_{2}O$  ₂   →  $H_2$  +  $O_2$

(iii)       They take up  $C{O}_2$ at night and prepare an intermediate, which is acted upon by the

energy absorbed by chlorophyll during the day