Improvement in Food Resources Questions and Answers Class 9

NCERT Solutions for Class 9 Science Chapter 12 Improvement in Food Resources Questions and Answers

Textbook Exercise

Q1. What do we get from cereals, pulses, fruits and vegetables?

Ans. Cereals, pulses (legumes), fruits, and vegetables provide various essential nutrients that are important for maintaining a healthy diet. Here’s what we generally get from each category:

Cereals: Carbohydrates, Dietary fiber, B vitamins, Minerals

Pulses (Legumes): Protein, Dietary fiber, Complex carbohydrates, Iron and minerals

Fruits: Vitamins and minerals, Dietary fiber, Antioxidants

Vegetables: Vitamins and minerals, Dietary fiber, Antioxidants, Phytochemicals: Vegetables contain various phytochemicals, such as carotenoids and flavonoids, which have been linked to reduced risk of chronic diseases.

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

Ans. Biotic factors, including diseases, insects, and nematodes, as well as abiotic factors such as drought, salinity, waterlogging, heat, cold, and frost, can lead to stress in crop plants. This stress often results in a decrease in crop production and, in severe cases, can even lead to the complete destruction of the entire crop.

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

Ans. Agronomic characteristics that are considered desirable in crop plants contribute to higher yields and increased productivity. For instance, tallness and profuse branching are desirable traits in fodder crops as they promote greater biomass production. On the other hand, dwarfness is a desirable characteristic in cereal crops as it allows for efficient nutrient utilization and reduces nutrient consumption by these crops. By selecting and breeding crop varieties with these specific traits, farmers can enhance productivity and optimize resource allocation in their agricultural systems.

Q1. What are macro-nutrients and why are they called macro-nutrients?

Ans. Macro-nutrients refer to the essential chemical elements that are required by plants in relatively large quantities for their growth and development. These include carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, and sulfur. These nutrients are commonly referred to as major or macro-nutrients due to their significant role in various physiological processes of plants. Plants obtain these macro-nutrients from the soil and utilize them for tasks such as photosynthesis, protein synthesis, energy production, and structural development. Their abundance and availability in the soil directly impact the plant’s overall health, growth, and productivity.

Q2. How do plants get nutrients?

Ans. Plants require a total of 16 essential nutrients for their growth and development, they acquire these nutrients from different sources.

1. Carbon (C) and Oxygen (O): These two elements are primarily obtained from atmospheric carbon dioxide (CO2) during the process of photosynthesis. Through photosynthesis, plants convert CO2 into carbohydrates, providing them with a source of carbon and oxygen.

2. Hydrogen (H): Hydrogen is mainly sourced from water (H2O). Plants absorb water through their roots, and during photosynthesis, water molecules are broken down, releasing hydrogen atoms that are used in various metabolic processes.

3. Macronutrients from Soil: The remaining 13 essential nutrients are obtained by plants from the soil. These macronutrients include:

   – Nitrogen (N)

   – Phosphorus (P)

   – Potassium (K)

   – Calcium (Ca)

   – Magnesium (Mg)

   – Sulfur (S)

4. Micronutrients from Soil: In addition to the macronutrients, plants also require smaller quantities of micronutrients, also known as trace elements. These include:

   – Iron (Fe)

   – Manganese (Mn)

   – Zinc (Zn)

   – Copper (Cu)

   – Molybdenum (Mo)

   – Boron (B)

   – Chlorine (Cl)

Plants absorb these nutrients from the soil through their root systems. 

Q1. Compare the use of manure and fertilizers in maintaining soil fertility.

Ans. Manures, rich in organic matter but low in nutrients compared to synthetic fertilizers, may not sufficiently meet crop nutrient requirements, leading to deficiencies and reduced yield. Excessive synthetic fertilizer use without organic matter incorporation can cause drainage issues and waterlogging, compromising soil structure and crop growth. Prolonged fertilizer use disrupts soil microorganism balance, hindering nutrient cycling and soil health. A balanced approach combining organic amendments with judicious fertilizer application, along with practices like crop rotation and conservation tillage, maintains soil fertility, nutrient cycling, and sustainable agriculture.

Q1. Which of the following conditions will give the most benefits? Why? 

(a) Farmers use high quality seeds, do not adopt irrigation or use fertilizers.

(b) Farmers use ordinary seeds, adopt irrigation and use fertilizer. 

(c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.

Ans. Conditions given in (c) are beneficial for farmers because use of:

1. High-quality seeds play a vital role in determining the genetic traits of crops, including resistance to pests and diseases, response to inputs, overall quality, and higher yield. By selecting and using quality seeds, farmers can ensure optimal crop performance.

2. Implementing appropriate irrigation methods ensures that crops receive adequate water at the right time, meeting their water requirements. Proper irrigation practices contribute to healthy crop growth and development.

3. Fertilizers supply essential nutrients that crops need for optimal growth. By providing the necessary nutrients, fertilizers support healthy plant development and maximize yield potential.

4. Crop protection measures are crucial for preventing losses caused by pests, diseases, and other factors. By implementing effective pest and disease management strategies, farmers can safeguard their crops and ultimately protect their yield.

Q1. Why should preventive measures and biological control methods be preferred for protecting crops.

Ans. Preventive measures and biological control are eco-friendly and safe methods for crop protection. They minimize environmental pollution, unlike chemical measures involving pesticide spraying or seed treatment. Practices like crop rotation, intercropping, and optimal plant health management reduce pest and disease risks, reducing the need for chemicals. Biological control utilizes natural enemies of pests, minimizing harm to non-target organisms. By prioritizing these approaches, farmers can minimize reliance on chemical pesticides, promoting sustainability.

Q2. What factors may be responsible for losses of grains during storage?

Ans. Several factors can contribute to the loss of grains during storage. Here are some common factors:

1. Moisture: Excessive moisture content in stored grains can lead to mold and fungal growth, causing spoilage and degradation of grain quality. 

2. Temperature: Inadequate temperature control can accelerate the rate of grain deterioration. High temperatures can promote insect activity and microbial growth, while extremely low temperatures can lead to moisture condensation and subsequent mold formation.

3. Pests and Insects: Insects such as beetles, weevils, and moths can damage grains by feeding on them and laying eggs, leading to contamination and spoilage.

4. Poor Storage Conditions: Improper storage conditions create an environment favorable for mold growth, pest infestation, and moisture accumulation.

5. Improper Handling: Rough handling of grains during storage can result in physical damage, leading to increased susceptibility to mold growth and pest infestation.

Q1. Which method is commonly used for improving cattle breeds and why?

Ans. Artificial Insemination is a method commonly used for improving cattle breeds because:

i. By artificial insemination many cows (up to 3000) can be fertilized by the semen collected from one bull.

ii. The semen of bulls can be collected, imported, and transported to distant locations within a country. This is made possible by the ability to freeze semen, allowing for long-term storage.

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.”

Ans. India is the 5th largest country in terms of poultry farming, with a significant focus on raising fowl. Poultry birds, such as chickens, can be efficiently raised on low-fiber food sources that are unsuitable for human consumption. Poultry farming provides a valuable source of both eggs and meat, particularly broiler chickens, which are known for their protein-rich content. Chicken and eggs are highly preferred poultry products among a large portion of the non-vegetarian population, due to their nutritional benefits and versatility in cooking.

Q1. What management practices are common in dairy and poultry farming?

Ans. Important points to remember in dairy and poultry farming include:

1. Housing and Hygiene: Providing proper housing with adequate space, ventilation, and cleanliness is crucial. Regular cleaning, sanitation, and periodic disinfection help maintain hygienic conditions and prevent disease transmission.

2. Vaccination: Implementing a vaccination program is essential for preventing infectious diseases. Vaccinating animals or birds according to recommended schedules helps protect them from various illnesses.

3. Selection of Quality Breeds: Choosing good quality breeds is vital for both dairy and poultry farming. Selecting breeds that are known for high milk production or superior meat quality ensures better productivity and profitability.

4. Space and Environmental Conditions: Sufficient space, proper lighting intensity, and appropriate temperature maintenance are important factors for animal comfort and well-being. Animals should have enough room to move, and lighting and temperature should be regulated to create a conducive environment.

5. Feeding Management: Proper feeding management is critical for optimal production. Providing a balanced and nutritious diet that meets the specific nutritional needs of dairy cattle or poultry helps promote good health, growth, and productivity.

Q2. What are the differences between broilers and layers in their management?

Ans. Broilers and layers are two distinct types of poultry birds, each bred for a specific purpose. Broilers are raised for meat production and are typically slaughtered at a young age, while layers are managed for their egg-laying abilities throughout their productive lives. Their management differs in several aspects. Broilers require a high-protein diet to support rapid growth, while layers need a balanced diet for egg production, including sufficient calcium. Housing requirements vary, with broilers raised in temperature-controlled environments and layers housed in systems that accommodate nesting areas. Lighting management differs as well, with broilers benefiting from continuous or extended lighting, while layers require specific lighting programs for optimal egg production. Understanding these variations is crucial for effective management and maximizing productivity in both broiler and layer farming.

Q1. How are fish obtained?

Ans. There are two primary methods of obtaining fish: capture fishing and fish farming, also known as culture fishery.

1. Capture Fishing: Capture fishing involves the harvesting of fish from natural resources such as oceans, rivers, lakes, and other bodies of water. It relies on various techniques like nets, traps, lines, and hooks to catch fish in their natural habitats. Capture fishing can be practiced on a small scale by individual fishermen or on a large scale by commercial fishing operations.

2. Fish Farming (Culture Fishery): Fish farming, also known as aquaculture or culture fishery, involves the cultivation of fish in controlled environments. This method involves raising fish in tanks, ponds, or other enclosed systems specifically designed for fish production. Fish farming allows for better control over factors such as water quality, temperature, feeding, and disease prevention. It can be practiced for different purposes, including food production, stock enhancement, and ornamental fish production.

Q2. What are the advantages of composite fish culture?

Ans. Composite fish culture, also known as integrated fish farming, offers several advantages for fish farmers. 

Firstly, it increases productivity by optimizing resource utilization and reducing competition for resources among different fish species. 

Secondly, it promotes nutrient cycling in the pond, with different species having varied feeding habits that help maintain a balanced ecosystem. 

Thirdly, by mixing different fish species, the risk of disease outbreaks can be minimized as some species have natural resistance or tolerance to certain diseases. 

Additionally, composite fish culture allows for efficient utilization of pond space, diversification of production to mitigate risks, and provides farmers with a diverse range of fish products, leading to increased income generation. Overall, it is a sustainable and economically viable approach to fish farming.

Q1. What are the desirable characters of bee varieties suitable for honey production?

Ans. Desirable characteristics of bees for beekeeping are as follows:

1. Good Honey Collection Capacity: It is preferable to have bees with a high capacity for collecting nectar and producing honey. This trait leads to increased honey production, which is beneficial for beekeepers.

2. Prolific Queen Production with Reduced Swarming: Beekeepers seek bee colonies that have queens capable of laying a large number of eggs. This results in the development of strong and populous colonies, while reducing the tendency for swarming. Minimizing swarming helps maintain the colony’s population and prevents the loss of bees.

3. Defensive Ability against Enemies: Bees that possess effective defense mechanisms against predators, pests, and diseases are advantageous for beekeeping. The ability to protect themselves from enemies contributes to the overall health and survival of the bee colony.

Q2. What is pasturage and how is it related to honey production?

Ans. Pasturage refers to the flora or crops found around an apiary that provide a source of nectar and pollen for honey bees. Examples of pasturage flora for honey bees include Mango, Coconut, Almond, Sisham, Apple, Tamarind, Mahua, Coriander, and more.

The quality and flavor of honey are influenced by the pasturage surrounding the apiary. Bees collect nectar and pollen from the available flora, and these sources directly impact the characteristics of the honey produced. For instance, in regions like Kashmir where almond plants are abundant around the apiary, the resulting honey is known as almond honey. Almond honey tends to have superior quality, taste, and aroma due to the influence of the almond plant pasturage.

Exercise

Q1. Explain any one method of crop production which ensures high yield.

Ans. Integrated Crop Management (ICM) is a holistic approach to farming that optimizes crop productivity while minimizing environmental impact. It integrates various practices such as crop rotation, soil management, pest control, irrigation, and nutrient management. ICM focuses on maintaining soil health and fertility through proper testing and nutrient application. Crop rotation breaks pest cycles and improves soil structure. Integrated pest management techniques are used to minimize chemical pesticide use. Water-saving techniques like drip irrigation are promoted, and balanced nutrient application prevents imbalances and maximizes uptake. Cultural, mechanical, and chemical weed control methods are employed. By implementing ICM, farmers can enhance productivity, reduce costs, and promote sustainable agriculture.

Q2. Why are manures and fertilizers used in fields?

Ans. Continuous cultivation of crops can deplete the nutrients in the soil over time. In order to replenish these nutrients and maintain soil fertility, farmers utilize manures and fertilizers. Manures are organic materials derived from animal waste or decomposed plant matter, while fertilizers are synthetic or naturally occurring substances rich in essential plant nutrients. These inputs are applied to the soil or crops to provide the necessary nutrients for healthy plant growth. Manures and fertilizers help to replenish nutrient levels, improve soil fertility, and support high crop yields. Their careful and judicious use is an important aspect of sustainable crop production.

Q3. What are the advantages of inter-cropping and crop rotation?

Ans. Intercropping offers several advantages. First, it reduces competition among crops for nutrients, leading to better overall yields. Second, intercropping disrupts pest cycles, lowering pest pressure and reducing the need for chemical pesticides. Third, it optimizes resource utilization by combining crops with complementary resource needs. This ensures efficient use of water, sunlight, and nutrients. Additionally, intercropping promotes biodiversity, supporting natural pest control and ecological balance. As for crop rotation, it improves soil fertility by replenishing specific nutrients. It also helps manage pests and diseases by breaking their cycles and reduces weed growth. Moreover, crop rotation prevents soil erosion by continuously covering the soil with vegetation. Overall, these practices promote sustainable and environmentally friendly agriculture.

Q4. What is genetic manipulation? How is it useful in agricultural practices?

Ans. Genetic manipulation involves incorporating desirable traits into organisms through techniques like hybridization, mutation, DNA recombination, and polyploidy. It finds significant applications in agriculture, enabling the development of improved seed varieties with traits like pest resistance, efficient input response, quality, and high yield potential. By utilizing these genetically manipulated seeds, farmers can enhance crop productivity while reducing input costs, thanks to the desired traits designed for improved performance and reduced dependency on additional inputs.

Q5. How do storage grain losses occur?

Ans. Storage grain losses can occur due to various factors, including pests and insects, fungal and bacterial infections, excessive moisture and humidity, temperature fluctuations, improper storage conditions, physical damage, and poor hygiene and sanitation. To minimize losses, proper storage practices such as regular inspection, temperature and humidity control, ventilation, the use of grain protectants, cleanliness, appropriate packaging, and rotation should be implemented. These measures help minimize spoilage, preserve grain quality, and protect stored grains from pests and microbial growth.

Q6. How do good animal husbandry practices benefit farmers?

Ans. Animal husbandry means scientific management of farm animals. By adopting good journal husbandry practices farm can

(i) reduce input cost e.g., keeping animals healthy and disease free. 

(ii) increase higher returns by breed improvement for higher yields.

Q7. What are the benefits of cattle farming?

Ans. Buffalo and cows are both valuable dairy animals. The male buffalo, known as a he-buffalo, and oxen from cows are utilized as bullock labor for various agricultural practices like tilling, irrigation, and carting. As a result, cattle farmers engage in cattle production for milk, draft purposes, and even for dual purposes, where they can benefit from both milk production and the utilization of cattle as labor animals.

Q8. For increasing production, what is common in poultry, fisheries and bee keeping?

Ans. Selection of an improved variety of poultry, fishes and honey bee.

Q9. How do you differentiate between capture fishing, mariculture and aquaculture?

Ans.