NEET Biology Mineral Nutrition MCQs Set 18

Answer: (a) macronutrients; micronutrients

Explanation:
1. Elements needed in amounts of more than about 10 mmol per kg of dry matter are macronutrients (for example C, H, O, N, P, K, Ca, Mg, S).
2. Those needed in amounts of less than 1 mmol per kg are micronutrients (for example Fe, Mn, Cu, Zn, B, Mo, Cl, Ni).

Teacher's Note:
1. M
2. a
3. c
4. r
5. o
6.
7. a
8. n
9. d
10.
11. m
12. i
13. c
14. r
15. o
16.
17. r
18. e
19. f
20. e
21. r
22.
23. t
24. o
25.
26. t
27. h
28. e
29.
30. a
31. m
32. o
33. u
34. n
35. t
36.
37. n
38. e
39. e
40. d
41. e
42. d
43. ,
44.
45. n
46. o
47. t
48.
49. t
50. o
51.
52. i
53. m
54. p
55. o
56. r
57. t
58. a
59. n
60. c
61. e
62. .
63.
64. B
65. o
66. t
67. h
68.
69. k
70. i
71. n
72. d
73. s
74.
75. a
76. r
77. e
78.
79. e
80. s
81. s
82. e
83. n
84. t
85. i
86. a
87. l
88. .

Answer: (a) Magnesium

Explanation:
1. The porphyrin ring of chlorophyll has magnesium at its centre.
2. Magnesium also holds the subunits of ribosomes together.

Teacher's Note:
1. M
2. a
3. g
4. n
5. e
6. s
7. i
8. u
9. m
10.
11. d
12. e
13. f
14. i
15. c
16. i
17. e
18. n
19. c
20. y
21.
22. c
23. a
24. u
25. s
26. e
27. s
28.
29. i
30. n
31. t
32. e
33. r
34. v
35. e
36. i
37. n
38. a
39. l
40.
41. c
42. h
43. l
44. o
45. r
46. o
47. s
48. i
49. s
50. ,
51.
52. f
53. i
54. r
55. s
56. t
57.
58. i
59. n
60.
61. o
62. l
63. d
64. e
65. r
66.
67. l
68. e
69. a
70. v
71. e
72. s
73. .

Answer: (a) leghaemoglobin

Explanation:
1. Leghaemoglobin is a pink pigment that acts as an oxygen scavenger in nodules.
2. It keeps the nodule interior anaerobic so that nitrogenase can function.

Teacher's Note:
1. L
2. e
3. g
4. h
5. a
6. e
7. m
8. o
9. g
10. l
11. o
12. b
13. i
14. n
15.
16. i
17. s
18.
19. s
20. i
21. m
22. i
23. l
24. a
25. r
26.
27. t
28. o
29.
30. h
31. a
32. e
33. m
34. o
35. g
36. l
37. o
38. b
39. i
40. n
41.
42. a
43. n
44. d
45.
46. i
47. s
48.
49. p
50. i
51. n
52. k
53.
54. i
55. n
56.
57. c
58. o
59. l
60. o
61. u
62. r
63. .

Answer: (a) nitrogenase

Explanation:
1. Nitrogenase, a Mo-Fe protein, reduces atmospheric nitrogen to ammonia.
2. Only some prokaryotes (nitrogen-fixers) possess it.

Teacher's Note:
1. N
2. i
3. t
4. r
5. o
6. g
7. e
8. n
9. a
10. s
11. e
12.
13. i
14. s
15.
16. h
17. i
18. g
19. h
20. l
21. y
22.
23. s
24. e
25. n
26. s
27. i
28. t
29. i
30. v
31. e
32.
33. t
34. o
35.
36. o
37. x
38. y
39. g
40. e
41. n
42. .

Answer: (a) Pseudomonas and Thiobacillus

Explanation:
1. Denitrifying bacteria such as Pseudomonas and Thiobacillus reduce nitrate to gaseous nitrogen.
2. Nitrosomonas and Nitrobacter carry out nitrification.

Teacher's Note:
1. D
2. e
3. n
4. i
5. t
6. r
7. i
8. f
9. i
10. c
11. a
12. t
13. i
14. o
15. n
16.
17. r
18. e
19. t
20. u
21. r
22. n
23. s
24.
25. n
26. i
27. t
28. r
29. o
30. g
31. e
32. n
33.
34. t
35. o
36.
37. t
38. h
39. e
40.
41. a
42. t
43. m
44. o
45. s
46. p
47. h
48. e
49. r
50. e
51. .

Answer: (a) 10%

Explanation:
1. A mineral ion concentration that decreases the dry weight of tissue by about 10 percent is considered toxic.

Teacher's Note:
1. T
2. h
3. e
4.
5. t
6. o
7. x
8. i
9. c
10. i
11. t
12. y
13.
14. t
15. h
16. r
17. e
18. s
19. h
20. o
21. l
22. d
23.
24. i
25. s
26.
27. d
28. e
29. f
30. i
31. n
32. e
33. d
34.
35. b
36. y
37.
38. i
39. t
40. s
41.
42. e
43. f
44. f
45. e
46. c
47. t
48.
49. o
50. n
51.
52. d
53. r
54. y
55.
56. w
57. e
58. i
59. g
60. h
61. t
62. .

Answer: (a) Carbon, hydrogen and oxygen are mainly obtained from \( CO_2 \) and \( H_2O \)

Explanation:
1. Plants build most of their carbon, hydrogen and oxygen from carbon dioxide and water; other elements come from soil.
2. Rhizobium induces invagination of root hairs, nitrogen is essential, and macronutrients are present in larger amounts.

Teacher's Note:
1. O
2. n
3. l
4. y
5.
6. t
7. h
8. e
9.
10. m
11. i
12. n
13. e
14. r
15. a
16. l
17.
18. e
19. l
20. e
21. m
22. e
23. n
24. t
25. s
26.
27. a
28. r
29. e
30.
31. a
32. b
33. s
34. o
35. r
36. b
37. e
38. d
39.
40. f
41. r
42. o
43. m
44.
45. t
46. h
47. e
48.
49. s
50. o
51. i
52. l
53. .

Answer: (b) Nitrogen, Phosphorus, Potassium

Explanation:
1. NPK stands for nitrogen, phosphorus and potassium, the three major plant nutrients in fertilisers.

Teacher's Note:
1. F
2. e
3. r
4. t
5. i
6. l
7. i
8. s
9. e
10. r
11.
12. l
13. a
14. b
15. e
16. l
17. s
18.
19. g
20. i
21. v
22. e
23.
24. t
25. h
26. e
27.
28. p
29. e
30. r
31. c
32. e
33. n
34. t
35. a
36. g
37. e
38.
39. o
40. f
41.
42. N
43. ,
44.
45. P
46.
47. a
48. n
49. d
50.
51. K
52. .

Answer: (a) xylem

Explanation:
1. Minerals absorbed by roots are carried upward in the xylem along with the transpiration stream.

Teacher's Note:
1. X
2. y
3. l
4. e
5. m
6.
7. c
8. a
9. r
10. r
11. i
12. e
13. s
14.
15. w
16. a
17. t
18. e
19. r
20.
21. a
22. n
23. d
24.
25. m
26. i
27. n
28. e
29. r
30. a
31. l
32. s
33. ;
34.
35. p
36. h
37. l
38. o
39. e
40. m
41.
42. c
43. a
44. r
45. r
46. i
47. e
48. s
49.
50. o
51. r
52. g
53. a
54. n
55. i
56. c
57.
58. f
59. o
60. o
61. d
62. .

Answer: (c) K

Explanation:
1. Potassium is not a part of any enzyme, but activates many enzymes and maintains turgor and stomatal opening.

Teacher's Note:
1. P
2. o
3. t
4. a
5. s
6. s
7. i
8. u
9. m
10.
11. i
12. s
13.
14. a
15. n
16.
17. a
18. c
19. t
20. i
21. v
22. a
23. t
24. o
25. r
26. ,
27.
28. n
29. o
30. t
31.
32. a
33.
34. s
35. t
36. r
37. u
38. c
39. t
40. u
41. r
42. a
43. l
44.
45. c
46. o
47. m
48. p
49. o
50. n
51. e
52. n
53. t
54. .

Answer: (a) photolysis of water

Explanation:
1. Manganese is involved in the photolysis of water in the light reaction.

Teacher's Note:
1. C
2. h
3. l
4. o
5. r
6. i
7. n
8. e
9.
10. i
11. s
12.
13. i
14. t
15. s
16.
17. p
18. a
19. r
20. t
21. n
22. e
23. r
24.
25. i
26. n
27.
28. t
29. h
30. i
31. s
32.
33. r
34. e
35. a
36. c
37. t
38. i
39. o
40. n
41. .

Answer: (c) Phosphorus is a constituent of cell membranes, certain nucleic acids and cell proteins

Explanation:
1. Phosphorus is a constituent of cell membranes (phospholipids) and nucleic acids, but not of cell proteins in general. So (c) is wrong.
2. Anabaena and Nostoc fix nitrogen when free-living, Rhizobium lives free-living as an aerobe, and Nitrosomonas and Nitrobacter are chemoautotrophs.

Teacher's Note:
1. P
2. r
3. o
4. t
5. e
6. i
7. n
8. s
9.
10. c
11. o
12. n
13. t
14. a
15. i
16. n
17.
18. s
19. u
20. l
21. p
22. h
23. u
24. r
25.
26. b
27. u
28. t
29.
30. n
31. o
32. t
33.
34. p
35. h
36. o
37. s
38. p
39. h
40. o
41. r
42. u
43. s
44.
45. a
46. s
47.
48. a
49.
50. t
51. y
52. p
53. i
54. c
55. a
56. l
57.
58. c
59. o
60. m
61. p
62. o
63. n
64. e
65. n
66. t
67. .

Answer: (c) pump; gravity

Explanation:
1. A pump lifts the solution to the higher end.
2. The slope lets it flow back to the reservoir under gravity.

Teacher's Note:
1. H
2. y
3. d
4. r
5. o
6. p
7. o
8. n
9. i
10. c
11. s
12.
13. g
14. r
15. o
16. w
17. s
18.
19. p
20. l
21. a
22. n
23. t
24. s
25.
26. i
27. n
28.
29. a
30.
31. n
32. u
33. t
34. r
35. i
36. e
37. n
38. t
39.
40. s
41. o
42. l
43. u
44. t
45. i
46. o
47. n
48.
49. w
50. i
51. t
52. h
53. o
54. u
55. t
56.
57. s
58. o
59. i
60. l
61. .

Answer: (c) A is true, but R is false.

Explanation:
1. Hydroponics is soilless culture in a nutrient solution, so A is true.
2. A balanced nutrient solution contains only the essential elements in the correct proportions, so R is false.

Teacher's Note:
1. S
2. o
3. l
4. u
5. t
6. i
7. o
8. n
9.
10. c
11. u
12. l
13. t
14. u
15. r
16. e
17.
18. i
19. s
20.
21. u
22. s
23. e
24. d
25.
26. t
27. o
28.
29. f
30. i
31. n
32. d
33.
34. w
35. h
36. i
37. c
38. h
39.
40. e
41. l
42. e
43. m
44. e
45. n
46. t
47. s
48.
49. a
50. r
51. e
52.
53. e
54. s
55. s
56. e
57. n
58. t
59. i
60. a
61. l
62. .

Answer: (b) Both A and R are true, but R is not the correct explanation of A.

Explanation:
1. Magnesium is in chlorophyll and activates enzymes like RuBisCO, so A is true.
2. Mg also activates enzymes of DNA and RNA synthesis, so R is true.
3. R does not explain A.

Teacher's Note:
1. M
2. a
3. g
4. n
5. e
6. s
7. i
8. u
9. m
10.
11. h
12. a
13. s
14.
15. s
16. e
17. v
18. e
19. r
20. a
21. l
22.
23. u
24. n
25. r
26. e
27. l
28. a
29. t
30. e
31. d
32.
33. r
34. o
35. l
36. e
37. s
38. .

Answer: (c) A is true, but R is false.

Explanation:
1. Sulphur is a part of amino acids such as cysteine and methionine, and its deficiency causes chlorosis, so A is true.
2. Chlorophyll and nucleic acids do not contain sulphur, so R is false.

Teacher's Note:
1. C
2. h
3. l
4. o
5. r
6. o
7. p
8. h
9. y
10. l
11. l
12.
13. c
14. o
15. n
16. t
17. a
18. i
19. n
20. s
21.
22. M
23. g
24.
25. a
26. n
27. d
28.
29. N
30. ;
31.
32. s
33. u
34. l
35. p
36. h
37. u
38. r
39.
40. i
41. s
42.
43. a
44.
45. p
46. a
47. r
48. t
49.
50. o
51. f
52.
53. p
54. r
55. o
56. t
57. e
58. i
59. n
60. s
61. .

Answer: (b) Both A and R are true, but R is not the correct explanation of A.

Explanation:
1. Iron is supplied as a chelate (Fe-EDTA) to keep it soluble and available, so A is true.
2. Hydroponics is expensive, so R is true.
3. The cost does not explain the use of a chelate.

Teacher's Note:
1. C
2. h
3. e
4. l
5. a
6. t
7. i
8. o
9. n
10.
11. k
12. e
13. e
14. p
15. s
16.
17. i
18. r
19. o
20. n
21.
22. f
23. r
24. o
25. m
26.
27. p
28. r
29. e
30. c
31. i
32. p
33. i
34. t
35. a
36. t
37. i
38. n
39. g
40. .

Answer: (b) A-II; B-I; C-IV; D-III

Explanation:
1. Mg\( ^{2+} \) activates RuBisCO and PEPcase: A-II.
2. Zn\( ^{2+} \) activates dehydrogenases: B-I.
3. K\( ^{+} \) controls stomatal opening: C-IV.
4. Phosphate is needed for phosphorylation reactions: D-III.

Teacher's Note:
1. L
2. i
3. n
4. k
5.
6. e
7. a
8. c
9. h
10.
11. i
12. o
13. n
14.
15. t
16. o
17.
18. i
19. t
20. s
21.
22. b
23. e
24. s
25. t
26. -
27. k
28. n
29. o
30. w
31. n
32.
33. r
34. o
35. l
36. e
37. .

Answer: (a) A-IV; B-V; C-I; D-II; E-III

Explanation:
1. Azotobacter and Beijerinckia are aerobic free-living fixers: A-IV.
2. Rhodospirillum is an anaerobic fixer: B-V.
3. Anabaena and Nostoc are cyanobacteria: C-I.
4. Pseudomonas and Thiobacillus denitrify: D-II.
5. Nitrosomonas and Nitrococcus nitrify: E-III.

Teacher's Note:
1. G
2. r
3. o
4. u
5. p
6.
7. t
8. h
9. e
10.
11. b
12. a
13. c
14. t
15. e
16. r
17. i
18. a
19.
20. b
21. y
22.
23. t
24. h
25. e
26. i
27. r
28.
29. r
30. o
31. l
32. e
33.
34. i
35. n
36.
37. t
38. h
39. e
40.
41. n
42. i
43. t
44. r
45. o
46. g
47. e
48. n
49.
50. c
51. y
52. c
53. l
54. e
55. .

Answer: (c) A-III; B-IV; C-I; D-II

Explanation:
1. Manganese splits water: A-III.
2. Zinc is needed for auxin synthesis: B-IV.
3. Molybdenum is a component of nitrate reductase and nitrogenase: C-I.
4. Boron is needed for pollen germination and sugar translocation: D-II.

Teacher's Note:
1. E
2. a
3. c
4. h
5.
6. m
7. i
8. c
9. r
10. o
11. n
12. u
13. t
14. r
15. i
16. e
17. n
18. t
19.
20. h
21. a
22. s
23.
24. a
25.
26. s
27. i
28. g
29. n
30. a
31. t
32. u
33. r
34. e
35.
36. f
37. u
38. n
39. c
40. t
41. i
42. o
43. n
44. .

Answer: (a) A-I, IV; B-V; C-II; D-III

Explanation:
1. K is a free ion in cells and opens stomata: A-I, IV.
2. Mo is a component of nitrogenase and nitrate reductase: B-V.
3. P is part of phospholipids of membranes: C-II.
4. Mn takes part in photolysis of water: D-III.

Teacher's Note:
1. P
2. o
3. t
4. a
5. s
6. s
7. i
8. u
9. m
10.
11. h
12. a
13. s
14.
15. n
16. o
17.
18. c
19. o
20. v
21. a
22. l
23. e
24. n
25. t
26.
27. r
28. o
29. l
30. e
31. ,
32.
33. s
34. o
35.
36. i
37. t
38.
39. e
40. x
41. i
42. s
43. t
44. s
45.
46. a
47. s
48.
49. a
50.
51. f
52. r
53. e
54. e
55.
56. i
57. o
58. n
59. .

Answer: (d) A-II; B-IV; C-I; D-III

Explanation:
1. Zinc is needed to make IAA: A-II.
2. Sulphur is in cysteine: B-IV.
3. Magnesium is in chlorophyll: C-I.
4. Molybdenum is in nitrate reductase: D-III.

Teacher's Note:
1. R
2. e
3. c
4. a
5. l
6. l
7.
8. o
9. n
10. e
11.
12. k
13. e
14. y
15.
16. c
17. o
18. m
19. p
20. o
21. u
22. n
23. d
24.
25. f
26. o
27. r
28.
29. e
30. a
31. c
32. h
33.
34. e
35. l
36. e
37. m
38. e
39. n
40. t
41. .

Answer: (d) nitrate

Explanation:
1. Most plants absorb nitrogen as nitrate ions, and some as ammonium, from the soil.

Teacher's Note:
1. N
2. i
3. t
4. r
5. a
6. t
7. e
8.
9. i
10. s
11.
12. t
13. h
14. e
15.
16. m
17. a
18. i
19. n
20.
21. f
22. o
23. r
24. m
25.
26. b
27. e
28. c
29. a
30. u
31. s
32. e
33.
34. n
35. i
36. t
37. r
38. i
39. f
40. i
41. c
42. a
43. t
44. i
45. o
46. n
47.
48. p
49. r
50. o
51. d
52. u
53. c
54. e
55. s
56.
57. i
58. t
59. .

Answer: (a) nitrogen

Explanation:
1. Nitrogen is required in the largest quantity among mineral elements, as it is in proteins, nucleic acids and chlorophyll.

Teacher's Note:
1. A
2. f
3. t
4. e
5. r
6.
7. C
8. ,
9.
10. H
11.
12. a
13. n
14. d
15.
16. O
17. ,
18.
19. n
20. i
21. t
22. r
23. o
24. g
25. e
26. n
27.
28. i
29. s
30.
31. t
32. h
33. e
34.
35. e
36. l
37. e
38. m
39. e
40. n
41. t
42.
43. n
44. e
45. e
46. d
47. e
48. d
49.
50. m
51. o
52. s
53. t
54. .