Which of the following macronutrient has role in the opening and closing of stomata?
a) K
b) N
c) O
d) C
Which of the following macromolecule is the part of chlorophyll and also acts as coenzyme?
a) S
b) Mg
c) P
d) Ca
Which of the following are the micronutrients in plant nutrients?
a) N, P, K, Ca, Mg, S
b) Mn, Zn, Mo, Co, Na
c) B, Cu, Fe, Cl
d) both b and c
Explanation: these are required in very less amount and are very essential
Which of the following is/are the best source/s of micronutrients for growing plants?
a) urea
b) recycling organic matters
c) ammonia
d) all of these
Explanation: e.g. grass clipping and leaves of trees is an excellent source
Which of the following micronutrient has role in nitrogen fixation in plants?
a) sodium
b) cobalt
c) molybdenum
d) zinc
Deficiency of which of the following cause chlorosis (yellowing) and necrosis of leaves?
a) N, P, K, Mg
b) Mn, Zn, Mo, Co, Na
c) B, Cu, Fe, Cl
d) Ca
