Mineral Nutrition Practice Questions - DPP for NEET

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DPP /CB12
1. (b) 2. (c)
3. (a) Molybdenum is a component of nitrogenase and nitrate
reductase involved during N
2
 fixation. Copper is essential
for photosynthesis and respiration. Zinc is involved in
synthesis of auxin. Manganese is activator of enzymes
involved in nitrogen metabolism.
4. (b) The root nodules of leguminous plants contain a symbiotic
nitrogen fixing bacteria Rhizobium. Root nodules are small
irregular outgrowth of the roots which are pinkish internally
due to presence of a pigment called leghaemoglobin. It is
related to blood pigment haemoglobin. The cells of root
nodules are tetraploid and contain polyhedral bacteria called
bacteroids. Leghaemoglobin is an oxygen scavenger and
protects the nitrogen fixing enzyme nitrogenase of
bacteroids.
5. (c) ‘Whip-tail’ disease in cauliflower is noted due to deficiency
of molybdenum. Cauliflower is the most sensitive of crops
to molybdenum (Mb) deficiency. Light sandy soils with pH
levels close to or below pH 6 under conditions of high fertility
can show severe Mb deficiency. Molybdenum is the only
plant essential micronutrient that becomes less available as
the soil acidifies–the opposite of copper, zinc and iron.
6. (b) The essential elements are divided into macroelements and
microelements    based on the quantity in which they are
required by the plants. Mn, Fe, Cu, Mo, Zn, B, and Cl
are the micronutrients needed in very small quantities by
the plants. C, H, O, N, P, S, K, Ca, Mg, Fe are the
macronutrients required in more quantity.
7. (d) Heterotrophic plants are less dependent on nitrogen obtained
from nitrification since they receive some nitrite and nitrate
through their parasitic or carnivorous nutritional modes.
8. (d) 9. (b)
10. (d) Root hairs absorb water, minerals and oxygen but they do
not absorb CO
2
. CO
2
 intake takes place in leaves.
11. (c) The ash that is left after burning any dry part of the plant
contains only mineral elements and is called plant ash.
12. (b) The atmospheric nitrogen is fixed in the soil in the form of
nitrate. Nitrate and ammonium can be taken up by plants or
used by other soil organisms. Any nitrate or ammonium that
is not used for growth is added to the pool of inorganic
nitrogen in the soil.
13. (c) Cultivation of plants by placing the roots in the nutrient
solution without any soil is called hydroponics. It is also
known as soilless culture/ water culture/ solution culture. It
is used to determine which elements are essential for plant
growth and what symptoms are produced by the absence or
deficiency of essential elements.
14. (c) 15. (c)
16. (a) Cobalt stimulates growth of legumes such as beans, clover
and alfalfa. This stimulation of growth by cobalt is due to its
use, not by the plant itself, but by nitrogen-fixing bacteria
that live in roots of plants.
17. (b) 18. (a) 19. (a) 20. (b) 21. (b)
22. (d)
23. (b) Magnesium activates the enzymes of respiration,
photosynthesis and is involved in the synthesis of DNA and
RNA. Manganese activates many enzymes which are
involved in photosynthesis, respiration and nitrogen
metabolism.
24. (a) NO
3
 
–
, is negatively charged and not tightly bound to soil
particles.
25. (d) Legume roots have swellings called nodules that contain
nitrogen-fixing bacteria of the genus Rhizobium.
26. (b) The main difference between micronutrients and
macronutrients is in how much of them a plant needs to
survive.
27. (c) Symptoms caused by deficiency of essential mineral elements
on plants are called Hunger signs.
28. (a) The deficiency of calcium results in death of leaf, stem and
root apices.
29. (c) Hydrogen sulphide has little to do with ion exchange.
30. (b) Due to immobile property of sulphur, chlorosis occurs first
in young leaves.
31. (c) All other statements are false.
32. (a) The characteristic symptom of iron deficiency is the
interveinal chlorosis. The symptom may be general or
localised to a single leaf or a single branch because of the
limited mobility of iron in the tissues. The deficiency
symptom first appears in young leaves.
33. (d) An iron deficiency is suspected in a plant. If the older leaves
are yellow, a nitrogen deficiency would be suspected because
nitrogen is easily relocated in the plant while iron is not.
34. (d) 35. (d)
36. (d) The bulk of the organic material of a plant is derived from
carbon dioxide assimilated from the atmosphere.
37. (b) For chlorophyll formation, a plant needs Fe, Mg & light
38. (c) 39. (a) 40. (b) 41. (c) 42. (a)
43. (b) "Reclamation" and "Little leaf" disease is caused by deficiency
of Cu and Zn.
44. (a) 45. (a)