IMPROVEMENT IN FOOD RESOURCES-Exercise
Biology - Exercise
Q1. Explain any one method of crop production which ensures high yield.
Answer:
One important method of crop production that ensures high yield is use of high-yielding varieties (HYV) of seeds. These are specially developed seeds that produce much more grain per plant compared to traditional seeds. Scientists create these improved varieties through selective breeding or hybridization to make them strong, disease-resistant, and suitable for different climatic conditions.
When farmers use HYV seeds along with proper irrigation, fertilizers, and pest control, the total production of crops like wheat, rice, and maize increases greatly. This method played a major role in the Green Revolution, which helped India achieve self-sufficiency in food grain production.
Q2. Why are manure and fertilizers used in fields?
Answer:
Manure and fertilizers are used in fields to replenish the nutrients that crops take up from the soil during their growth. When plants grow, they absorb essential elements like nitrogen, phosphorus, and potassium from the soil to make food and develop properly. After several crop cycles, the soil becomes poor in these nutrients and loses its natural fertility.
-
To restore this fertility, farmers add manure or fertilizers.
- Manure is organic in nature and improves the soil’s structure, water-holding capacity, and microbial activity.
- Fertilizers are chemical substances rich in specific nutrients that directly provide plants with the minerals they need for faster and healthier growth.
Thus, the use of manure and fertilizers helps in maintaining soil health, promoting better crop growth, and ensuring higher yields for sustainable agriculture.
Q3. What are the advantages of inter-cropping and crop rotation?
Answer:
Inter-cropping and crop rotation are scientific farming methods that help in increasing productivity and maintaining soil fertility.
Inter-cropping:
In this method, two or more crops are grown together on the same field in a definite pattern. For example, maize and beans can be grown side by side. This reduces the risk of total crop failure, makes better use of nutrients from the soil, and prevents the spread of pests and diseases that usually attack a single crop type.
Crop rotation:
This involves growing different crops one after another on the same land in different seasons. For instance, a farmer may grow wheat in one season and legumes in the next. This practice helps in replenishing soil nutrients naturally—especially nitrogen—since leguminous plants fix nitrogen in the soil.
Advantages:
- Maintains the natural fertility of the soil.
- Reduces pest and disease attacks.
- Ensures better use of nutrients.
- Provides higher yield and balanced production.
- Minimizes dependence on chemical fertilizers.
Q4. What is genetic manipulation? How is it useful in agricultural practices?
Answer:
Genetic manipulation is the process of changing or modifying the genetic material (DNA) of an organism to obtain desirable traits. Scientists use special techniques to transfer useful genes from one organism to another. This process helps create improved varieties of plants and animals with specific beneficial characteristics such as higher yield, disease resistance, or better adaptability to environmental conditions.
Usefulness in agricultural practices:
- High-yielding crops:
Genetic manipulation helps in developing crop varieties that produce more grains or fruits per plant. - Pest and disease resistance:
It allows plants to resist insects, pests, and plant diseases, reducing the need for harmful chemical pesticides. - Improved nutritional value:
Crops can be modified to contain more vitamins, proteins, or minerals, making food more nutritious. - Tolerance to environmental stress:
Genetically improved crops can tolerate drought, salinity, or extreme weather conditions, ensuring stable production. - Better storage and shelf life:
Some genetically modified crops stay fresh for longer periods, reducing post-harvest losses.
Q5. How do storage grain losses occur?
Answer:
Storage grain losses occur when freshly harvested grains are not stored properly and get damaged by various
biotic and abiotic factors. These losses can happen during handling, drying, or long-term storage and may
reduce both the quantity and quality of the stored food grains.
Biotic factors
- Insects and pests feed on grains and make them hollow.
- Rodents and birds eat and scatter stored grains, leading to wastage.
- Fungal growth occurs in damp conditions, making the grains unfit for human use.
These are living organisms that spoil grains. They include insects, rodents, birds, fungi, and bacteria.
Abiotic factors
- High moisture causes rotting and fungal infection.
- Improper temperature can lead to sprouting or decay of grains.
- Poor ventilation increases dampness, encouraging pest attack.
These are non-living conditions like moisture, temperature, and humidity.
To prevent such losses, grains should be properly dried before storage, kept in clean, airtight containers, and stored in pest-free, dry godowns.
Q6. How do good animal husbandry practices benefit farmers?
Answer:
Good animal husbandry practices involve the scientific management and care of farm animals such as cattle,
poultry, sheep, goats, and fish to ensure their healthy growth and high productivity. These practices
include providing proper nutrition, shelter, hygiene, breeding, and healthcare to the animals.
Benefits to farmers:
- Increased production:
Healthy and well-fed animals produce more milk, meat, eggs, wool, and other products, which directly increases the farmer’s income. - Better quality products:
Proper feeding and disease control improve the quality of animal products, making them more nutritious and suitable for market demand. - Reduced disease risk:
Regular vaccination, cleanliness, and proper housing protect animals from infections and reduce losses due to illness or death. - Efficient breeding:
Scientific breeding methods help in producing animals with superior traits such as higher milk yield or faster growth. - Sustainable livelihood:
Animal husbandry provides a steady source of income throughout the year and supports rural families even when crop production is low.
Q7. What are the benefits of cattle farming?
Answer:
Benefits of Cattle Farming
Cattle farming means rearing cows, buffaloes, or other cattle for useful products. It has several important advantages for farmers and society:- Milk Production:
Cows and buffaloes are our main sources of milk. Milk is a nutritious food rich in protein, calcium, vitamins, and essential fats. This helps in making products like cheese, curd, butter, ghee, paneer, and sweets. - Meat Production:
Some cattle breeds are reared for meat. This adds to our food variety and helps meet the protein needs of many people. - Agricultural Support:
Cattle like bullocks are used for ploughing fields, transporting goods, and other farm work, especially in villages where machines are less common. - Organic Manure:
Cow dung and urine can be used as natural fertilizers (manure). This improves soil fertility, reduces dependence on chemical fertilizers, and supports healthy crop growth. - Biogas Production:
Cow dung is also used for making biogas, a clean fuel that can be used for cooking and lighting, especially in rural homes. - Income Generation:
Cattle farming provides regular income to farmers through sale of milk, meat, hides, and other cattle products. It also creates jobs in dairy, transport, and allied industries. - By-products:
Leather, bone, and horn obtained from cattle are used in various industries for making shoes, belts, medicines, and handicrafts.
Q8. For increasing production, what is common in poultry, fisheries and bee-keeping?
Answer:
For increasing production, what is common in poultry, fisheries and bee-keeping?
The most important thing common to poultry, fisheries, and bee-keeping for increasing production is
scientific management. This means using improved techniques and careful practices to take care of birds,
fish, or bees so that they grow well and stay healthy.
Key points in scientific management common to all three:
- Selection of good breeds or species:
Choosing birds, fish, or bees with high productivity, disease resistance, and better quality. - Proper nutrition:
Giving balanced and nutritious feed or food to ensure healthy growth and higher yields. - Controlled environment:
Keeping their living space clean, safe, and protected from harsh weather, pests, and diseases. - Regular monitoring and care:
Checking health, providing vaccinations or medicines as needed, and quickly treating any diseases. - Efficient practices:
Using advanced equipment and latest methods for breeding, feeding, and harvesting to get maximum output.
Q9. How do you differentiate between capture fishing, mariculture and aquaculture?
Answer:
| Feature | Capture Fishing | Mariculture | Aquaculture |
|---|---|---|---|
| Definition | Collecting fish from natural sources like rivers, lakes, and oceans with little human control | Cultivation of marine (sea) organisms in the open sea or near the shore | Rearing of aquatic plants and animals (like fish, prawns) in controlled water bodies |
| Method | Wild fish are caught using nets, hooks, or traps | Marine organisms (fish, oysters, prawns) are raised or grown with human care | Both freshwater and marine creatures are bred, fed, and harvested systematically |
| Area/ Environment | Natural water bodies (rivers, lakes, seas, oceans) | Seawater environments (coastal areas, marine farms) | Artificial or controlled ponds, tanks, rivers, or enclosures |
| Human Intervention | Very minimal; mainly just harvesting | Moderate to high; involves feeding and protection | High; complete control over breeding, feeding, disease management |
| Examples | Traditional fishing from the sea or rivers | Farming of fish, seaweed, oysters in ocean cages | Fish ponds, shrimp farms, tank fish farming |
| Main Output | Wild-caught fish and seafood | Cultivated marine species for food and trade | Cultivated aquatic species (freshwater or saltwater) for consumption and business |
