Extra 20 important long questions and answers from the chapter:15 "Improvement in Food Resources" for Class 9 Science (CBSE):-
1. What are the major factors for improving crop production?
✅ Answer:
Crop variety improvement
– Using high-yield and disease-resistant varieties.
Nutrient management
– Proper use of fertilizers and manure.
Irrigation
– Sufficient water supply through canals, wells, and rainwater harvesting.
Crop protection
– Use of pesticides, herbicides, and biological control.
Storage and marketing
– Proper storage to prevent spoilage and good distribution channels.
Sustainable farming methods
– Organic farming, mixed cropping, and crop rotation.
2. What is hybridization in plants? How is it beneficial?
✅ Answer:
Hybridization is cross-breeding two genetically different plant varieties to produce a new variety with desired traits.
Benefits:
Higher yield
– Hybrid crops give more produce per hectare.
Disease resistance
– Better immunity against common plant diseases.
Improved quality
– Better taste,
colour
, and nutritional value.
Shorter growth period
– Faster maturity and harvesting.
Tolerance to environmental stress
– Better adaptability to drought or floods.
Higher market value
– Due to better quality and yield.
3. Explain the different types of cropping patterns used in agriculture.
✅ Answer:
Mixed Cropping
– Growing two or more crops together (e.g., wheat + gram).
Intercropping
– Growing two crops in alternate rows for better nutrient utilization.
Crop Rotation
– Changing the type of crop grown in a field each season to maintain soil fertility.
Relay Cropping
– Sowing the next crop before harvesting the current one.
Multiple Cropping
– Growing more than one crop in a year on the same land.
Monoculture
– Growing a single crop over a large area (common in commercial farming).
4. What are fertilizers? How are they different from manures?
✅ Answer:
Fertilizers are chemical substances that provide essential nutrients to crops.
Differences:
|
Feature |
Fertilizers |
Manures |
|---|---|---|
|
Composition |
Chemically synthesized |
Natural organic matter |
|
Nutrient content |
High and specific |
Low and varied |
|
Action |
Quick release of nutrients |
Slow release |
|
Effect on soil |
Can cause pollution and soil degradation |
Improves soil texture and fertility |
|
Cost |
Expensive |
Cheaper |
5. What are the advantages and disadvantages of organic farming?
✅ Answer:
Advantages:
Eco-friendly
– No chemical fertilizers or pesticides.
Improves soil health
– Increases soil fertility and water retention.
Better quality food
– No harmful chemicals in crops.
Sustainable farming
– Maintains biodiversity.
Safe for farmers
– No exposure to toxic chemicals.
Disadvantages:
Lower yield
– Compared to chemical farming.
Takes longer
– Organic methods take more time to improve soil.
Higher cost
– Organic food is expensive.
Limited pest control
– Natural pest control methods are less effective.
Requires more
labour
– Manual weeding and composting need extra effort.
6. Why is irrigation important in crop production?
✅ Answer:
Ensures proper water supply
– Essential for plant growth.
Improves soil moisture
– Helps in seed germination.
Increases crop yield
– Avoids drought-related crop loss.
Prevents soil erosion
– Keeps the soil structure intact.
Supports multiple cropping
– More than one crop can be grown in a year.
Reduces dependency on rainfall
– Essential in dry areas.
7. What is drip irrigation? Mention its advantages.
✅ Answer:
Drip irrigation is a technique where water is supplied directly to plant roots drop by drop.
Advantages:
Saves water
– Reduces wastage.
Prevents weed growth
– Water is given only to crops.
Improves crop yield
– Plants get water as per their requirement.
Works in dry areas
– Suitable for deserts.
Reduces soil erosion
– No water runoff.
Less
labour-intensive
– Automated systems available.
8. What are weeds? How can they be controlled?
✅ Answer:
Weeds are unwanted plants that grow with crops and compete for nutrients, water, and sunlight.
Control methods:
Manual removal
– Uprooting weeds by hand.
Weedicides
– Chemical weed killers (e.g., 2,4-D).
Crop rotation
– Different crops suppress weed growth.
Mulching
– Covering soil with straw to prevent weeds.
Biological control
– Using insects or fungi to destroy weeds.
Ploughing and tilling
– Uproots weeds before sowing.
9. What are the main objectives of animal husbandry?
✅ Answer:
Increase milk production
– Better cattle breeds.
Improve meat and egg production
– High-quality poultry and fishery.
Better disease resistance
– Vaccination and hygiene.
Efficient breeding techniques
– Artificial insemination for better livestock.
Increase wool and silk production
– High-yielding sheep and silkworms.
Reduce human effort
– Use of draught animals in farming.
10. What is poultry farming? Mention its benefits.
✅ Answer:
Poultry farming is raising domestic birds like hens, ducks, and turkeys for eggs and meat.
Benefits:
Protein-rich food
– Eggs and chicken.
Quick growth and reproduction
– Fast yield.
Requires less space
– Can be done in small areas.
High market demand
– Eggs and meat are widely consumed.
Multiple breeds available
– Indigenous and exotic breeds.
By-products
– Feathers, manure, and fertilizers.
11. What are the different types of fish farming?
✅ Answer:
Marine fisheries
– Fishing in seawater (e.g., Tuna, Pomfret).
Inland fisheries
– Fishing in lakes, ponds, and rivers (e.g., Rohu, Catla).
Composite fish culture
– Different fish species in one pond.
Capture fishery
– Fishing from natural water bodies.
Culture fishery
– Artificial breeding in controlled environments.
12. What is apiculture? Mention its advantages.
✅ Answer:
Apiculture is the rearing of honeybees for honey and wax production.
Advantages:
Honey production
– Nutritional and medicinal value.
Wax production
– Used in candles, cosmetics.
Pollination assistance
– Bees help in crop production.
Low-cost farming
– Requires minimal investment.
Provides employment
– Farmers can earn extra income.
13. What is sericulture? Explain its importance.
✅ Answer:
Sericulture is the rearing of silkworms for silk production. The primary species used is Bombyx mori.
Importance:
Silk production
– Used in textiles and clothing.
Employment generation
– Provides jobs to farmers and workers.
High export value
– Silk is in high demand worldwide.
Uses in industries
– Silk is used in medical sutures and cosmetics.
Encourages mulberry farming
– Silkworms feed on mulberry leaves, boosting its cultivation.
Eco-friendly industry
– Sericulture is sustainable and does not harm the environment.
14. What are the different types of fertilizers? Give examples.
✅ Answer:
Fertilizers are substances that provide nutrients to plants for better growth.
Types:
Nitrogenous fertilizers
– Supply nitrogen (e.g., Urea, Ammonium
sulphate
).
Phosphatic fertilizers
– Supply phosphorus (e.g., Superphosphate).
Potassic fertilizers
– Supply potassium (e.g., Potassium chloride).
Complex fertilizers
– Contain two or more nutrients (e.g., NPK fertilizer).
Biofertilizers
– Contain living microbes (e.g., Rhizobium,
Azotobacterial
).
Organic fertilizers
– Manure and compost that enrich the soil naturally.
15. What are the harmful effects of chemical fertilizers?
✅ Answer:
Soil degradation
– Reduces soil fertility over time.
Water pollution
– Runoff leads to eutrophication in water bodies.
Harmful to microorganisms
– Kills beneficial soil bacteria.
Health hazards
– Contaminated crops may cause diseases.
High cost
– Expensive for small-scale farmers.
Leads to overuse
– Excess fertilizers can make the soil saline.
16. How does composite fish culture help in increasing fish production?
✅ Answer:
Composite fish culture is a technique where different species of fish are raised together in a pond.
Advantages:
Efficient use of resources
– Different species use different levels of the pond.
Increases fish yield
– More production per unit area.
Minimizes competition
– Each fish species has different food requirements.
Maintains ecological balance
– Reduces overpopulation of a single species.
Better profit for farmers
– Multiple species lead to a higher income.
Prevents diseases
– Reduces the spread of infections among fish.
17. What are the major challenges in increasing food production?
✅ Answer:
Limited land availability
– Agricultural land is decreasing due to urbanization.
Water scarcity
– Overuse of groundwater and irregular rainfall.
Soil degradation
– Overuse of fertilizers and pesticides.
Climate change
– Extreme weather conditions affect crops.
Pest and disease attacks
– Reduce crop yield.
Post-harvest losses
– Poor storage and transport lead to food wastage.
18. How does proper storage help in food conservation?
✅ Answer:
Prevents spoilage
– Protects food from pests and microorganisms.
Reduces wastage
– Ensures food is available for longer periods.
Maintains nutritional value
– Stops food from decaying.
Helps in price stabilization
– Stored food can be used in times of scarcity.
Improves market supply
– Farmers can sell food when prices are better.
Ensures food security
– Essential for feeding the growing population.
19. What are genetically modified (GM) crops? Give two examples.
✅ Answer:
Genetically Modified (GM) crops have been scientifically altered to improve yield, pest resistance, and nutrient content.
Examples:
Bt Cotton
– Resistant to bollworm pests.
Golden Rice
– Rich in vitamin A to prevent blindness.
Advantages of GM Crops:
Higher yield
– More food production.
Pest resistance
– Reduces pesticide use.
Drought tolerance
– Can grow in dry areas.
Improved nutrition
– More vitamins and minerals.
Longer shelf life
– Reduced spoilage.
Better adaptability
– Withstand environmental changes.
20. Why is fish farming better than capturing fish from natural sources?
✅ Answer:
Fish farming (aquaculture) involves rearing fish under controlled conditions, while capture fishing depends on natural fish populations.
Advantages of Fish Farming:
Sustainable production
– Prevents overfishing in rivers and oceans.
Higher yield
– More fish per unit area.
Disease control
– Monitored environment reduces infections.
Continuous supply
– Fish are available throughout the year.
Less environmental damage
– Reduces pressure on natural fish populations.
Improved fish quality
– Controlled diet leads to better taste and nutrition.
