Session 1: Plant Nutrients
Unit 5: Plant Nutrition and Irrigation
Textual Question-Answers
Check Your Progress
Fill in the Blanks
1. The elements necessary for metabolic activities of an organismare referred to as ———————
Ans: nutrients
2. The process of supplying nutrients and their intake is known as—————
Ans: nutrition
3. Green plants draw carbon from the atmosphere —————
Ans: carbon dioxide
4. Accessory structural elements are also called ———————
Ans: secondary nutrients
5. The mass developed after rotting of the organic matter is termedas ———————
Ans: manure
Multiple Choice Questions
1. ————— elements are necessary for the growth of plants.
(a) 16
(b) 14
(c) 10
(d) 12
Ans: (a) 16
2. The elements required by plants in large amounts are called —————
(a) micro-elements
(b) macro-element
(c) Both (a) and (b)
(d) None of the above
Ans: (b) macro-element
3. Accessory structural elements are —————
(a) K, Ca, Mg
(b) Cl, Br, I
(c) N, P, S
(d) C, H, O
Ans: (a) K, Ca, Mg
4. The application of manures in soil increases the ———————
(a) biological activities of soil
(b) physiological activities of soil
(c) moisture retention capacity of soil
(d) All of the above
Ans: (d) All of the above
5. The solid platy residue left after the extraction of oil is known as—————
(a) oil
(b) oil cake
(c) essence
(d) None of the above
Ans: (b) oil cake
6. Plant manures are composed of material from ———————
(a) plant origin
(b) animal origin
(c) Both (a) and (b)
(d) None of the above
Ans: (a) plant origin
7. Plant nutrients manufactured commercially through chemical processes are ———————
(a) fertilisers
(b) biofertilisers
(c) manure
(d) green manures
Ans: (a) fertilisers
8. Fertilisers that supply more than a single nutrient are called ———————
(a) sole fertilisers
(b) manures
(c) biofertiliser
(d) mix fertilisers
Ans: (d) mix fertilisers
Subjective Questions
1. How can plant nutrients be classified according to their functionsin plants?
Ans: According to their functions, plant nutrients are classified intostructural nutrients, accessory structural nutrients, regulators and carriers, andcatalysts and activators.
2. How are manures different from fertilisers?
Ans: Manures are organic in nature, bulky and supply nutrients slowlywhile improving soil structure, whereas fertilisers are inorganic, concentratedand supply nutrients quickly to plants.
3. Write down the advantages and disadvantages of fertiliserapplication.
Ans: Advantages of fertiliser application include quick availability ofnutrients, increased crop yield and ease of application. Disadvantages includesoil degradation, pollution, nutrient imbalance and harmful effects on soil microorganisms if used excessively.
4. What are the different types of fertilisers?
Ans: The different types of fertilisers are straight fertilisers, mixedfertilisers and complex fertilisers.
Match the Columns
A
1. Structural nutrients
2. Accessory structural
3. Regulators and carriers
4. Catalysts and activators
B
(a) Fe, B, Mo
(b) K, Ca, Mg
(c) N, P, S
(d) C, H, O
Ans: 1 – (d) C, H, O
2 – (b) K, Ca, Mg
3 – (c) N, P, S
4 – (a) Fe, B, Mo
