63.
Match List-I (Horizons of soil profile) with List-II (Contents) and select the correct answer:
List-I List-II
a. O-horizon 1. Composed of fresh or partially decomposed organic material
b. A-horizon 2. Composed of weathered parent material
c. B-horizon 3. Composed of major organic matter, accumulated by the loss of clay, iron and aluminium
d. C-horizon 4. Composed of consolidated rock
e. R-horizon 5. Composed of alluvial concentration of all or any of the silicates, clay, iron, aluminium and humus, alone or in combination

64.
Plants with crassulacean acid metabolism (CAM plants) exhibit different stomatal behaviour in that

69.
According to Yoda and Kira (1963), the principles of population regulation include:

70.
The growth movements resulting from a difference between the rates of extension growth on opposite sides of an organ is called as