AIIMS 2013 Biology Question Paper for free online practice with solutions

The efficiency of C4 plants is more than thoseof C3 plants because (i) C4 plants are more efficientin picking up CO2 even when it is found in lowconcentration because of the high affinity of PEP,(ii) concentric arrangement of mesophyll cellsproduces a smaller area in relation to volume forbetter utilization of available water and reduce the intensity of solar radiations, (iii) they cantolerate excess salts because of the presence oforganic acids, (iv) normal oxygen concentrationis not inhibitory for the growth in contrast to C3plants, (v) they are adapted to high temperatureand intense radiation of tropics.