Fill in the blanks and choose the correct option given below.

(i) 4-C compounds like or formed in mesophyll cell of C 4 plants are transported to the bundle sheath.

(ii) The bundle sheath cells are rich in an enzyme but lacks .

(iii) pathway is common to C 3 and C 4 plants.

(iv) The active site of RuBisCO has both and binding sites. It has great affinity for .

(v) PGA binds with O 2 to form one molecule of and in a pathway called photorespiration.

(vi) C 4 acid from the mesophyll is broken down in the bundle sheath cells to release - this results in increasing the concentration of .

(vii) is the major limiting factor for photosynthesis.

(viii) Increase in concentration upto % can cause an increase in CO 2 fixation rates; beyond this the level can become damaging over longer periods.

(ix) C 4 plants show saturation at about µlL -1 while C 3 responds to increased CO 2 concentration and saturation is seen only beyond µlL -1 .