1. Choose the correct option.
a. Which of the following is a kharif crop?
i. Wheat
ii. Gram
iii. Ragi
iv. Mustard
Answer: iii. Ragi
b. The process of removal of the husk or chaff from the grains is called:
i. threshing
ii. reaping
iii. irrigating
iv. winnowing
Answer: iv. winnowing
c. Conversion of nitrogen gas into biologically available nitrogen such as ammonia, is called:
i. Ammonification
ii. denitrification
iii. nitrification
iv. nitrogen fixation
Answer: iv. nitrogen fixation
d. Which among the following are known as ‘farmer’s friends’?
i. insects
ii. fungi
iii. earthworms
iv. rats
Answer: iii. earthworms
e. Pisciculture is the rearing of:
i. bees
ii. fish
iii. poultry
iv. cattle
Answer: ii. fish
2. Assertion-Reasoning questions.
(i) Assertion (A): An instrument called cultivator is used to plough the soil.
Reason (R): It is faster than a plough and hoe and saves time and labour.
Answer: (a) Both A and R are true and R is the correct explanation of A. (A cultivator is a modern, tractor-driven tool that is indeed faster and more efficient than traditional tools.)
(ii) Assertion (A): Growing of different crops in succession on a field is called crop rotation.
Reason (R): The nitrogen utilised by leguminous crops are replenished by the cereal crops.
Answer: (c) Assertion (A) is true, but Reason (R) is false. (Crop rotation is correct. However, the reason is false; it is the leguminous crops (like peas, beans) that replenish soil nitrogen with the help of nitrogen-fixing bacteria, not the cereal crops.)
(iii) Assertion (A): Weeds must be removed to obtain higher yield of healthy crop plants.
Reason (R): Weeds compete with the crop plant for nutrients, water, space and light.
Answer: (a) Both A and R are true and R is the correct explanation of A. (Weeds are unwanted plants that compete with crops for all essential resources, and their removal (weeding) is crucial for a healthy yield.)
3. Answer the following questions in one sentence.
a. Name a commonly used weedicide.
Answer: 2,4-D 2,4-Dichlorophenoxyacetic acid is a commonly used weedicide.
b. What are the two most used modern methods of irrigation?
Answer: The two most used modern methods of irrigation are sprinkler irrigation and drip irrigation.
c. What are cash crops?
Answer: Cash crops are plants grown primarily for sale to return a profit, rather than for use by the farmer (e.g., cotton, tea, coffee, rubber).
d. Which tools are used for the physical removal of weeds?
Answer: A khurpi (trowel) and a hoe are used for the physical removal of weeds.
4. Answer the following questions in 2-3 sentences.
a. What is the difference between sprinkler irrigation and drip irrigation? (Write any two points)
Answer:
- Method: Sprinkler irrigation uses overhead pipes with nozzles that sprinkle water like rain over the crop. Drip irrigation uses a network of pipes with emitters that release water drop by drop directly at the base/roots of each plant.
- Efficiency: Drip irrigation is more water-efficient as it minimizes evaporation and runoff, making it ideal for water-scarce areas and fruit plants. Sprinklers are better suited for lawns and large fields.
b. What is a seed drill? How does it sow seeds into the soil?
Answer: A seed drill is a modern sowing tool that is attached to a tractor. It has a funnel connected to tubes leading to furrowers. It sows seeds uniformly at proper depth and distance, covers them with soil, and protects them from birds.
c. What do you mean by animal husbandry? Which products do we obtain from animals?
Answer: Animal husbandry is the branch of agriculture concerned with the care, breeding, and management of domesticated animals. We obtain products like milk, meat, eggs, wool, leather, and honey from animals.
d. How does a fallow field help in increasing soil fertility?
Answer: Leaving a field fallow (uncultivated) for one or more seasons allows the soil to naturally regain its lost nutrients, especially nitrogen, through the decomposition of organic matter and the action of microorganisms.
5. Answer the following questions in 3-4 sentences.
a. What are the advantages of ploughing?
Answer: The advantages of ploughing (tilling) are:
- It loosens the soil, allowing for better root penetration and growth.
- It aerates the soil, enabling soil microbes to breathe and thrive.
- It helps in mixing manure and fertilizers evenly with the soil.
- It brings nutrient-rich soil to the top and burrows weeds, helping in their removal.
b. List out the different methods that are used to increase soil fertility.
Answer: The different methods used to increase soil fertility are:
- Adding manure: It enriches the soil with organic matter and nutrients.
- Adding fertilizers: They provide specific essential nutrients like nitrogen, phosphorus, and potassium.
- Crop rotation: Growing leguminous crops in alternation with others helps replenish soil nitrogen.
- Keeping fields fallow: Allowing land to rest helps it recover lost nutrients naturally.