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Q1. What do we get from cereals, pulses, fruits and vegetables?
Answer: Cereals provide carbohydrates for energy; pulses supply proteins; fruits and vegetables offer vitamins, minerals, and dietary fiber.

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Q1. How do biotic and abiotic factors affect crop production?

Answer : Ways in which biotic and abiotic factors affect crop production are :

1. Biotic factors – These are living organisms such as pests, insects, rodents, weeds, fungi, bacteria, and viruses. They damage crops by feeding on them, spreading diseases, or competing for nutrients, leading to reduced yield and quality.
2. Abiotic factors – These are non-living environmental conditions such as drought, floods, extreme temperatures, salinity, and nutrient deficiency. They stress the plants, slow growth, and lower productivity.

Q2. What are the desirable agronomic characteristics for crop improvements?

Answer: Desirable agronomic characteristics for crop improvements are-

1. Tallness in fodder crops – Provides more biomass for animal feed.
2. Dwarfness in cereals – Prevents lodging (falling over) and allows plants to bear more grains.
3. Early maturity – Reduces the crop’s exposure to pests, diseases, and adverse weather, and allows multiple cropping.
4. Resistance to pests and diseases – Ensures healthy growth and better yield.
5. High nutrient-use efficiency – Better growth even in less fertile soils.

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Q1. What are macro-nutrients and why are they called macro-nutrients?
Answer: Macronutrients are nutrients required by plants in large quantities for their proper growth and development. Examples include nitrogen, phosphorus, potassium, calcium, magnesium, and sulphur. They are called “macro” because plants need them in larger amounts compared to micronutrients, which are required only in small quantities.

Q2. How do plants get nutrients?
Answer: Plants obtain nutrients mainly from the soil through their roots. Root hairs absorb mineral nutrients dissolved in water in the form of ions such as nitrate, phosphate, and potassium. In addition, plants get carbon and oxygen from carbon dioxide in the air, and hydrogen from water, which is absorbed by the roots.

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Q1. Compare the use of manure and fertilizers in maintaining soil fertility.
Answer: Manure is an organic material obtained from the decomposition of plant and animal waste. It improves soil fertility by adding humus, enhancing water-holding capacity, and supplying nutrients slowly over time. It also improves soil texture and promotes beneficial microbial activity. Fertilizers, on the other hand, are chemical substances rich in specific nutrients such as nitrogen, phosphorus, and potassium. They provide nutrients quickly and in precise amounts, leading to immediate improvement in crop yield. However, excessive use of fertilizers can degrade soil quality, harm microorganisms, and cause water pollution.

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Q1. Which of the following conditions will give the most benefits? Why?
(a) Quality seeds, no irrigation or fertilizers.
(b) Ordinary seeds, irrigation and fertilizers.
(c) Quality seeds, irrigation, fertilizers, and crop protection.

Answer: (c) Quality seeds plus irrigation, fertilizers, and crop protection, because it maximizes genetic potential, ensures water and nutrient availability, and protects against losses, leading to highest, most reliable yields.

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Q1. Why should preventive measures and biological control methods be preferred for protecting crops?
Answer: Preventive measures and biological control methods are preferred because they reduce the chances of pests and diseases affecting crops, minimizing the need for harmful chemical pesticides. These methods are eco-friendly, help maintain soil fertility, protect beneficial organisms, and reduce environmental pollution. They also prevent pests from developing resistance to chemicals.

Q2. What factors may be responsible for losses of grains during storage?
Answer: Losses of grains during storage can occur due to several factors such as moisture, high temperature, and poor storage conditions. Attack by insects, rodents, and fungi can damage the stored grains. In addition, improper handling, inadequate drying before storage, and contamination by microorganisms are major causes of spoilage and loss.

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Q1. Which method is commonly used for improving cattle breeds and why?
Answer: The most commonly used method for improving cattle breeds is cross-breeding. In this method, animals of a local breed are mated with animals of a superior foreign breed. This helps combine the desirable qualities of both breeds, such as high milk yield, better adaptability to local conditions, and improved resistance to diseases, resulting in healthier and more productive cattle.

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Q1. 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.”
Answer: The statement means that poultry birds such as hens and broilers can consume agricultural by-products and low-fibre feed materials that humans cannot eat, and efficiently convert them into eggs and meat, which are rich in high-quality protein. This process makes poultry farming a cost-effective and sustainable source of nutrition. It helps reduce food wastage, improves farmers’ income, and provides affordable animal protein to a large population, contributing to better food security and nutrition in India.

Q1. What management practices are common in dairy and poultry farming?
Answer: Both dairy and poultry farming require hygienic housing, balanced nutrition (roughage plus concentrates for cattle; formulated feeds for poultry), regular health care with vaccination, and proper waste disposal to prevent disease.

Q2. What are the differences between broilers and layers and in their management?
Answer: Layers are bred for high egg production and require diets rich in calcium and appropriate lighting to stimulate laying. Broilers are bred for rapid weight gain and require high-protein, energy-dense feeds for muscle growth. Housing density and shelter duration also differ.

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Q1. How are fish obtained?
Answer: Fish are obtained by capture fisheries (wild harvest from oceans, rivers, and lakes) and culture fisheries (aquaculture, including freshwater pond culture and mariculture in coastal or brackish waters).

Q2. What are the advantages of composite fish culture?
Answer: Composite fish culture uses multiple species with different feeding zones (surface, mid-water, bottom, and weed feeders) together in one pond, maximizing feed utilization, reducing competition, and increasing overall yield.

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Q1. What are the desirable characters of bee varieties suitable for honey production?
Answer: Ideal honeybee varieties have high honey-gathering capacity, low aggressiveness, strong colony strength, good adaptation to local climate, and longevity in hives.

Q2. What is pasturage and how is it related to honey production?
Answer: Pasturage refers to the availability of nectar-producing flowers around the apiary. A diverse and abundant floral source ensures bees collect sufficient nectar, improving honey yield and quality.