Are you preparing for competitive exams such as NEET, ACT or SAT? You are in the right place.
In this article, I am about to share the 30 most probable objective questions from the chapter "Mineral Nutrition", which might be helpful for your exam preparation. This chapter discusses the ways by which plants and animals get their nutrition from inorganic materials. Alongside the questions, we have also provided detailed explanations for every answer so that you can clear your doubts.
For chapter-wise MCQ questions, visit the following links:
Questions
1. Enzyme nitrogenase is responsible for
a) Nitrification
b) Nitrogen fixation
c) Nitrite reduction
d) Nitrate reduction
2. Nitrifying bacteria
a) Liberate ammonia
b) Change ammonia into ionic form
c) Oxidise ammonia to nitrate
d) Oxidise ammonia to nitrite
3. Plants growing near the nuclear test sites take up and accumulate which of the following elements?
a) Gold
b) Selenium
c) Strontium
d) All of these
4. Name the minerals responsible for maintaining cation-anion balance in the plant cells
a) K+ and Fe+3
b) Cl- and K+
c) Ca+2 and Mg+2
d) Cl- and Mg+2
5. What is the major function of air stone?
a) Remove CO2 content from the nutrient solution
b) Dissolves O2 in the nutrient solution
c) Increases the level of N2 in the nutrient solutions
d) Removes O2 from the nutrient solution
6. In hydroponic vegetables, the pH preferred by most vegetables is slightly
a) Alkaline
b) Neutral
c) Acidic
d) Basic
7. Which of the following are considered the roles of iron (Fe) in plants?
I. An important constituent of cytochrome
II. Activator of catalase
III. Essential for chlorophyll synthesis
Choose the correct option
a) Only I
b) Only III
c) Only II
d) All of these
8. By applying which of the following practices, contamination of hydroponics plants can be reduced?
a) Change the medium every week
b) Do not use tools from the outdoor garden
c) Complete aeration in a hydroponic tank
d) All of the above
9. An essential element is that which
a) Improves the health of the plant
b) Is irreplaceable and indispensable for the growth of plants
c) Is found in plant ash
d) Is available in the soil
10. Essential elements perform many functions which include
I. Permeability of the cell membrane
II. Maintenance of osmotic concentration of the cell sap
III. Major constituents of macromolecules and coenzymes
IV. Buffering action
Choose the correct option
a) Only III
b) I and III
c) Only I
d) I, II and III
11. Which of the following metals causes harmful effects?
a) Lead
b) Cobalt
c) Uranium
d) All of these
12. Nitrogen is mainly absorbed in the form of
a) Nitrate
b) Nitrite
c) Ammonium
d) All of these
13. In the initial phase of minerals absorption ions are taken up
a) Slowly
b) Rapidly
c) Fluently
d) Simultaneously
14. Which of the following is true regarding manganese toxicity in plants?
a) Induction deficiencies of iron, magnesium, and calcium
b) Appearance of brown spots surrounded by chlorotic veins
c) Inhibition of Ca^(2+) ions translocation in the shoot apex
d) All of the above
15. Sulphur is found as a constituent in which of the following amino acids?
a) Cysteine
b) Methionine
c) Both (a) and (b)
d) None of the above
16. What is the key principle of the EBB and flow system in hydroponics?
a) It floods and drains periodically
b) It makes a tide flowing over the roots
c) It sprays a mist of nutrients on the roots
d) None of the above
17. Hydroponics has been successfully employed as a technique for which of the following vegetables?
a) Seedless cucumber
b) Tomato
c) Lettuce
d) All of these
18. For the uptake of ions in the second phase of absorption of minerals, the pathway followed is called
a) Passive uptake
b) Active uptake
c) Neutral
d) None of these
19. How many essential mineral elements have been discovered yet?
a) 17
b) 107
c) 110
d) 150
20. Which of the following is a rootless aquatic plant in which a portion of the leaf forms a tiny sac for trapping insects?
a) Nepenthes
b) Drosera
c) Utricularia
d) Dionaea
21. Which of the given options is correct for hydroponics? Select the correct pair
I. Hydroponics technique is useful in areas having infertile and dry soils
II. Hydroponics can regulate pH optimum for a particular crop
III. It increases the labor cost
IV. It increases the problem of weeding
a) I and IV
b) I and II
c) I and III
d) Only I
22. Phosphorus is absorbed by the plants as
I. H_2 PO_4^- II. HPO_4
III. HPO_4^(2-) IV. H_2 PO^-
a) Only I
b) Only III
c) I and III
d) Only II
23. Insectivorous plants eat the insect for
a) Na-K
b) Nitrogen
c) Chlorine
d) Phosphorus
24. Aeroponics are
a) Aerial plants
b) Aerated plants
c) Soilers cultivated plants
d) None of these
25. The given diagram belongs to bacteroids in the nodule. Identify A and B and choose the correct option accordingly
a) A-Bacteria; B-Bacteroids
b) A-Leghaemoglobin; B-Bacteroides
c) A-Bacteroids; B-Bacteria
d) A-Bacteroids; B-Leghaemoglobin
26. Insectivorous plants eat insects for their requirement of
a) Sodium-potassium
b) Nitrogen
c) Chlorine
d) Phosphorus
27. Molybdenum is the essential constituent of
a) Nitrogenase
b) Respiratory chain
c) Growth regulators
d) Chlorophyll
28. Select the correct statement.
a) Legumes are incapable of fixing nitrogen
b) Legumes fix nitrogen through bacteria living in fruits
c) Legumes fix nitrogen only by bacteria present in root nodules
d) None of the above
29. Which among the following are used as media for hydroponics?
a) Coco air
b) Rock cool
c) Gravel
d) All of these
30. The core metal of chlorophyll is
a) Fe
b) Mg
c) Ni
d) Cu
Answers
1-b 2-c 3-c 4-b 5-b 6-c 7-d 8-d 9-b 10-d 11-d 12-a 13-b 14-d 15-c 16-a 17-d 18-b 19-a 20-c 21-b 22-c 23-b 24-c 25-c 26-b 27-a 28-c 29-c 30-b
Solutions
1 (b)
The fixation of nitrogen in root nodules of legumes takes place in the presence of the enzyme ‘nitrogenase’. This enzyme is an enzyme complex consisting of two components called protein-1 and protein-2. The active nitrogenase complex contains protein-1 and protein-2 components in a ratio of 1:2.
2 (c)
Ammonia produced by the degradation of manures and organic matter may not be available to plants because it is readily leached from soil. It is converted to nitrate with the help of certain microorganisms, i.e., called nitrification (the used bacteria, nitrifying bacteria).
2 NH3 + 3 O2 → 2 NO2- + 2H+ + 2 H2O
2NO2- + O2 → 2 NO2-
Ammonia is first oxidized to nitrite by the bacteria Nitrosomonas and/or Nitrosococcus. The nitrite is further oxidized to nitrate with the help of the bacterium Nitrobacter.
3 (c)
Some plant species accumulate selenium, some others gold, while some plants growing near nuclear test sites take up radioactive strontium.
4 (b)
Functions of Cl- It helps photolysis of water, maintenance of solute concentration, and ionic balance.
The function of K Potassium plays an important role in the opening and closing of stomata. These both can alter the osmotic potential of a cell
5 (b)
An air pump used in conjunction with an air stone is an excellent way to dissolve oxygen in the nutrient solution
6 (c)
An ideal pH range for most hydroponic crops is between 5.5 and 6.5.
It is important because it affects the availability and absorption of several of the 16 atomic elements needed for plant growth
7 (d)
Functions of Fe It is involved in the transfer of electrons like ferredoxin and cytochromes. It is reversibly oxidized from Fe2+ and Fe3+ during electron transfer. It activates catalase enzymes and is essential for the formation of chlorophyll
8 (d)
All of the above
9 (b)
Essential element has the following features:
1. It is indispensable for the growth of plants.
2. Cannot be replaced by any other element.
3. Absence/deficiency produces disorders.
4. Has nutritive value.
5. Necessary for completion of the vegetative or reproductive phase.
6. These are- C, H, O, N, P, K, S, Mg, Ca, Fe, B, Mn, Cu, Zn, Mo and Cl.
10 (d)
Essential elements perform several functions. They participate in various metabolic processes in the plant cells, such as permeability of the cell membrane, maintenance of osmotic concentration of the cell sap, electron transport systems, buffering action, enzymatic activities, and acts as a major constituent of macromolecules and coenzymes
11 (d)
All lead, cobalt, and uranium cause harmful effects.
12 (a)
Nitrogen is mainly absorbed in the form of nitrate from soil.
13 (b)
In the initial phase, ions are taken up rapidly.
14 (d)
The prominent symptom of manganese toxicity is the appearance of brown spots surrounded by chlorotic veins.
It is important to know that manganese competes with iron and magnesium for its uptake by the plants and with magnesium for its binding with enzymes. Manganese also inhibits calcium translocation in the shoot apex. Therefore, excess of manganese may induce deficiencies of iron, magnesium, and calcium.
15 (c)
Plant obtains sulfur in the form of sulfate (SO42-). Sulfur is present in two amino acids-cysteine and methionine and is the main constituent of several coenzymes, vitamins, and ferredoxin.
16 (a)
The EBB and flow system works by temporarily flooding the grown tray with nutrition solution and then draining the solution back into the reservoir.
17 (d)
Hydroponics has been successfully employed as a technique for the commercial production of vegetables such as tomatoes, seed less cucumbers, and lettuce.
18 (b)
For the uptake of ions in the second phase, the pathway followed is called active uptake.
19 (a)
17 elements are essential for plant growth.
20 (c)
Utricularia or bladderwort is an insectivorous submerged aquatic plant. In which the rootless floating stem bears highly dissected leaves. A portion of the leaf is modified into sacs, like bladders of about 1.3 mm in diameter. Each bladder is guarded by a small valve which opens inwardly. Small insects flow into the bladder with water, but cannot come out due to the valve.
21 (b)
Hydroponics technique is useful in areas having infertile and dry soils and can regulate the pH optimum for a particular crop.
22 (c)
Phosphorus is absorbed by the plants from soil in the form of phosphate ions either as H2PO4- or HPO42-.
23 (b)
Insectivorous plants are autotrophic in their mode of nutrition but they grow in marshy or muddy soils, which are generally deficient in nitrogen, and in other to fulfil their nitrogen requirements, these plants catch and digest small insects.
24 (c)
Aeroponics is soilless cultivated of plants
25 (c)
A-leghaemoglobin, B-bacteroids
26 (b)
Insectivorous plants eat insects for nitrogen
27 (a)
Enzyme nitrogenase is required for biological nitrogen fixation. It is a metal protein. The metal present in the nitrogenase enzyme is molybdenum. Hence, molybdenum is an important element for nitrogen fixation.
28 (c)
The legumes (papilionaceous plants) are incapable of nitrogen fixation. The Rhizobium bacteria are present symbiotically in the root nodules of these plants which have the capability of nitrogen fixation.
29 (c)
Coco air, perlite, rock cool, and gravel all are used as media for hydroponics
30 (b)
In the center of each chlorophyll molecule is found a magnesium metal.
These questions will be helpful in the preparation and revision of the chapter "Mineral Nutrition". Thanks for visiting my website.
