Improvement in Food Resources – NCERT Solutions for Class 9 Science Chapter 15
In this chapter of Class 9 Science, we explore the crucial topic of Improvement in Food Resources, focusing on how agricultural practices and animal husbandry contribute to increased food production. With growing populations and the need for sustainable food security, understanding the methods of improving crop yield, breeding better varieties of plants and animals, and adopting modern techniques is essential. Here, we provide detailed NCERT Solutions for Chapter 15, answering all important questions from the textbook, along with explanations, definitions, and additional tips for mastering this chapter. Whether you're preparing for exams or looking to improve your understanding, this guide offers a comprehensive approach to this essential topic.
Quick Summary of Chapter 15: Improvement in Food Resources (Class 9 Science)
Chapter 15 of Class 9 Science focuses on methods to improve food production and ensure food security. It highlights the importance of crop production through improved agricultural practices like irrigation, crop rotation, and use of fertilizers and pesticides. The chapter also covers animal husbandry, including breeding, care, and management of animals for better productivity. Key topics like green revolution, crop varieties, and sustainable farming practices are discussed to show how technology and modern techniques can enhance food resources. The chapter emphasizes the need for environmentally friendly practices to ensure food availability for the growing population.
Page No. 204
1. What do we get from cereals, pulses, fruits and vegetables?
Ans: From cereals, pulses, fruits, and vegetables, we get essential nutrients that are vital for our health:
- Cereals (like wheat, rice, maize) provide carbohydrates for energy.
- Pulses (such as lentils, peas) are rich in proteins for muscle growth and repair.
- Fruits and vegetables offer vitamins, minerals, and fiber, which are important for immunity, digestion, and overall health.
Page No. 205
1. How do biotic and abiotic factors affect crop production?
Ans: Biotic and abiotic factors both play important roles in crop production:
Biotic factors (like pests, diseases, and weeds) can harm crops and reduce their growth.
Abiotic factors (like climate, soil, and water) affect how well crops grow. Poor weather or bad soil can limit crop production.
2. What are the desirable agronomic characteristics for crop improvements?
Ans: The desirable agronomic characteristics for crop improvements include:
- High Yield – Producing more crops per unit of land.
- Disease Resistance – Ability to resist pests and diseases.
- Drought Tolerance – Ability to grow with limited water.
- Early Maturity – Faster growth to harvest crops earlier.
- Good Quality – Better taste, size, and nutritional value.
- Stress Resistance – Tolerance to extreme weather conditions like heat or cold.
(Write the number of points according to marks in the question)
Page No. 206
1. What are macro-nutrients and why are they called macro-nutrients?
Ans: Macro-nutrients are nutrients plants need in large amounts, like nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur, for healthy growth. They are called "macro" because they are required in big quantities.
2. How do plants get nutrients?
Ans: Plants get nutrients from the soil through their roots. The soil contains essential nutrients like water, minerals, and other elements, which are absorbed by the roots to support plant growth. Some nutrients are also absorbed from the air, like carbon dioxide for photosynthesis.
Page No. 207
1. Compare the use of manure and fertilizers in maintaining soil fertility.
Ans: Manure is organic material that improves soil structure, retains moisture, and adds nutrients gradually, enhancing soil health over time.
Fertilizers are chemicals that provide specific nutrients quickly but can degrade soil quality if used excessively.
Effects of Manure:
- Improves soil texture
- Increases water retention
- Enhances long-term fertility
Effects of Fertilizer:
- Provides quick nutrients for fast plant growth
- Increases crop yield in the short term
- Can reduce soil organic matter and harm soil microbes if overused
Page No. 208
1. Which of the following conditions will give the most benefits? Why?
(a) Farmers use high-quality seeds, do not adopt irrigation or use fertilizers.
(c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.
Ans: The most beneficial condition would be:
(c) Farmers use quality seeds, adopt irrigation, use fertilizer, and use crop protection measures.
Reason:
This combination ensures optimal growth of crops. Quality seeds provide better yield, while irrigation and fertilizers provide essential water and nutrients for healthy crop growth. Crop protection measures help protect the plants from diseases, pests, and other threats, ensuring higher productivity and better overall crop health.
Page No. 209
1. Why should preventive measures and biological control methods be preferred for protecting crops?
Ans: Preventive measures and biological control methods should be preferred for protecting crops because they are eco-friendly, reduce the use of harmful chemicals, and promote sustainable farming. These methods help in maintaining the balance of the ecosystem and prevent the development of pest resistance.
2. What factors may be responsible for losses of grains during storage?
Ans: Factors responsible for grain losses during storage include:
- Pest infestation (insects, rodents, fungi).
- Moisture (high moisture content can lead to mold growth).
- Improper storage conditions (poor ventilation and inadequate temperature control).
- Physical damage (broken grains or rough handling).
- Contamination (dirt or foreign materials).
- Storage duration (long storage times can lead to spoilage).
(Write the number of points according to marks in the question)
Page No. 210
1. Which method is commonly used for improving cattle breeds and why?
Ans: The method commonly used for improving cattle breeds is selective breeding. In this method, cattle with desirable traits, like higher milk yield or better growth, are chosen to reproduce. This helps in producing better quality offspring over time.
Page No. 211
1. Discuss the implications of the following statement:
“It is interesting to note that poultry is India’s most
efficient converter of low fibre food stuff (which is unfit for human
consumption) into highly nutritious animal protein food”.
Ans: The statement means that poultry efficiently converts low-fiber, inedible materials (like crop waste) into nutritious food (eggs and meat) for humans.
Implications:
- Waste Utilization: Poultry helps recycle food waste into valuable protein.
- Cost-Effective: It provides affordable, high-quality animal protein.
- Sustainable: It reduces the need for expensive feed and supports eco-friendly food production.
Page No. 211
1. What management practices are common in dairy and poultry farming?
Ans: Common management practices in dairy and poultry farming include:
- Feeding: Providing balanced nutrition.
- Housing: Ensuring clean and comfortable shelters.
- Health Care: Regular vaccination and disease prevention.
- Breeding: Selective breeding for improved productivity.
- Cleanliness: Maintaining hygiene to prevent infections.
- Record Keeping: Tracking production and health data.
- Routine Collection: Timely milking and egg collection for optimal yield.
(Write the number of points according to marks in the question)
2. What are the differences between broilers and layers and in their management?
Ans: A poultry bird raised for meat is called a broiler, and a bird raised for eggs is called a layer. Broilers and layers have different housing, food, and environmental needs. Broilers are fed a protein-rich diet with some fat and higher levels of vitamins A and K. Layers, on the other hand, need more space and proper lighting to lay eggs effectively.
Page No. 213
1. How are fish obtained?
Ans: Fish are obtained through fishing from natural water bodies or through fish farming (aquaculture), where they are raised in controlled environments.
2. What are the advantages of composite fish culture?
Ans: Composite fish culture offers several benefits: it increases fish yield by stocking different species together, uses resources more efficiently, reduces the risk of disease, boosts profits by offering various fish types, and promotes sustainable farming practices.
Page No. 213
1. What are the desirable characters of bee varieties suitable for honey production?
Ans: Desirable characteristics of bee varieties suitable for honey production include:
- High Honey Yield: Bees that produce a large quantity of honey.
- Gentleness: Calm and non-aggressive behavior for easy handling.
- Good Disease Resistance: Ability to resist common bee diseases.
- Strong Swarming Tendency: Moderate swarming behavior for better colony management.
- Efficient Foraging: Ability to gather nectar from a wide variety of plants.
- Overwintering Ability: Ability to survive during cold weather and ensure honey production in the next season.
(Write the number of points according to marks in the question)
2. What is pasturage and how is it related to honey production?
Ans: Pasturage is the supply of nectar and pollen from flowering plants that bees collect. It is important for honey production because more and better pasturage means bees can produce more honey.
NCERT Solutions for Class 9 Science Chapter 15: Improvement in Food Resources
1. Explain any one method of crop production which ensures high yield.
Ans: One method of crop production that ensures high yield is use of high-quality seeds. By selecting and planting high-quality, disease-resistant seeds, farmers can grow healthier crops that are more productive and resistant to pests and diseases, leading to a higher yield.
2. Why are manure and fertilizers used in fields?
Ans: Manure and fertilizers are used in fields to improve soil fertility, providing essential nutrients like nitrogen, phosphorus, and potassium that plants need to grow. They help increase crop yield, enhance plant growth, and restore nutrients in the soil that may be depleted after each harvest.
3. What are the advantages of inter-cropping and crop rotation?
Answer: Advantages of using inter-cropping:
Ans: Advantages of inter-cropping:
- Increases yield by using land more efficiently.
- Reduces pests and diseases.
- Improves soil fertility.
- Makes better use of resources like water and sunlight.
Advantages of crop rotation:
- Maintains soil health by preventing nutrient depletion.
- Controls pests and diseases.
- Enhances soil fertility, especially with nitrogen-fixing crops.
- Leads to better long-term yields.
(Write the number of points according to marks in the question)
4. What is genetic manipulation? How is it useful in agricultural practices?
Ans: Genetic manipulation is the process of altering the DNA of an organism to enhance desired traits, such as better resistance to diseases, pests, or environmental conditions.
In agriculture, genetic manipulation is useful because:
- It can produce crops with higher yields.
- It helps create disease-resistant crops, reducing the need for chemical pesticides.
- It enables the development of crops that tolerate harsh climates like drought or extreme temperatures.
- It can improve nutritional value of crops, like adding vitamins or minerals.
5. How do storage grain losses occur?
Ans: Storage grain losses occur due to pest infestation, moisture, improper storage conditions, physical damage, contamination, and long storage duration. These factors can cause grains to spoil or decrease in quality.
6. How do good animal husbandry practices benefit farmers?
Ans: The benefits of cattle farming include:
- Milk Production: Provides a steady source of milk and dairy products.
- Meat Production: Supplies beef for food consumption.
- Manure: Cattle manure is used as a natural fertilizer for crops.
- Leather: Cattle hides are used to make leather products.
- Economic Value: Creates income and employment opportunities for farmers.
- Soil Health: Cattle grazing can help maintain healthy grasslands and prevent soil erosion.
(Write the number of points according to marks in the question)
7. For increasing production, what is common in poultry, fisheries and bee-keeping?
Ans: To increase production, poultry, fisheries, and bee-keeping all focus on selective breeding, improved feeding, disease control, proper management, and the use of modern techniques.
8. How do you differentiate between capture fishing, mariculture, and aquaculture?
Ans: Capture fishing refers to catching wild fish from natural water bodies like oceans, rivers, and lakes.
Mariculture is the farming of marine organisms, such as fish, shellfish, and seaweed, in coastal or ocean environments.
Aquaculture involves farming aquatic organisms (both freshwater and marine) in controlled environments like ponds, tanks, or pens.