NCERT Chapter 12 Class 9 Questions and Answers: FREE PDF Download
NCERT Solutions for Class 9 Science Chapter 12 Improvement In Food Resources
FAQs on NCERT Solutions for Class 9 Science Chapter 12 Improvement In Food Resources
1. How do the NCERT Solutions for Class 9 Science Chapter 12 explain the nutritional value we get from cereals, pulses, fruits, and vegetables?
The NCERT solutions clarify the specific contributions of different food types. Cereals like wheat and rice are primary sources of carbohydrates for energy. Pulses such as grams and lentils provide essential proteins for growth and repair. Fruits and vegetables supply a rich mix of vitamins and minerals, along with small amounts of proteins, carbohydrates, and fats.
2. What is the step-by-step method to explain how biotic and abiotic factors affect crop production, as per NCERT Solutions?
The solutions outline the following factors:
- Biotic factors: These are living organisms that reduce crop yield. Examples include pests (like insects) that eat parts of the plant, diseases caused by pathogens (bacteria, fungi, viruses), and weeds that compete for nutrients, light, and water.
- Abiotic factors: These are non-living environmental factors. Examples include drought (lack of water), salinity (excess salt in soil), waterlogging, extreme heat or cold, and frost, all of which can destroy crops.
3. According to NCERT solutions, what are the desirable agronomic characteristics for improving cereal and fodder crops?
The solutions state that desirable agronomic traits depend on the crop type. For cereal crops like wheat, dwarfness is a desired trait because shorter plants are stronger, can withstand wind, and consume fewer nutrients, allowing more to be used for grain production. For fodder crops, which are used as animal feed, the desired traits are tallness and profuse branching to maximise the amount of vegetative matter produced.
4. How do NCERT solutions differentiate between macronutrients and micronutrients for plants?
NCERT solutions explain the difference based on the quantity required by the plant. Macronutrients are essential elements needed in large quantities, such as nitrogen, phosphorus, potassium, calcium, magnesium, and sulphur. In contrast, micronutrients are needed in very small amounts, including iron, manganese, boron, zinc, copper, molybdenum, and chlorine.
5. What is the correct way to compare the use of manure and fertilisers for maintaining soil fertility, based on the Chapter 12 solutions?
The solutions provide a clear comparison. Manure is an organic substance that supplies small quantities of nutrients but greatly improves soil health by adding humus, which enhances water retention and soil structure. Fertilisers are commercially produced chemicals that supply specific nutrients like nitrogen, phosphorus, and potassium in high concentrations for immediate plant growth. However, overuse of fertilisers can degrade soil quality and cause water pollution, making a combined approach often the best solution.
6. Why is a combination of high-quality seeds, irrigation, fertilisers, and crop protection considered the most beneficial farming practice in the NCERT Solutions?
The NCERT solutions explain that each component addresses a different limiting factor for crop growth. Using only one component in isolation is inefficient. High-quality seeds have high genetic potential for yield, but this potential can only be realised if the plants receive adequate water (irrigation) and nutrients (fertilisers). Finally, crop protection measures are essential to prevent pests and diseases from destroying the crop, thus safeguarding the investment in seeds, water, and nutrients.
7. What is the difference between crop variety improvement and crop protection management as explained in Chapter 12?
These are two distinct but related agricultural practices. Crop variety improvement focuses on enhancing the intrinsic qualities of the crop itself through techniques like hybridisation and genetic modification. The goal is to create new varieties with higher yield, better quality, and resistance to diseases. Crop protection management, on the other hand, involves practices applied in the field to protect the growing and stored crops from harm, such as controlling weeds, pests, and pathogens.
8. How do the NCERT Solutions for Class 9 explain the difference between capture fishing, mariculture, and aquaculture?
The solutions differentiate these methods based on the source and technique.
- Capture fishing is the process of catching fish from their natural habitats, like oceans, rivers, and lakes.
- Mariculture is a specialised form of aquaculture focused on cultivating marine organisms (like prawns, oysters, and certain fish) in a marine environment, such as open oceans or coastal estuaries.
- Aquaculture is the broader term for farming aquatic organisms, including fish, molluscs, and crustaceans, in controlled freshwater or saltwater environments like ponds and tanks.
9. What are the key advantages of composite fish culture according to the NCERT solutions?
The NCERT solutions highlight two main advantages of composite fish culture, where multiple fish species are raised in the same pond. Firstly, it leads to a higher overall fish yield. Secondly, it ensures the full utilisation of food resources in the pond. This is achieved by selecting species with different feeding habits (e.g., surface feeders, middle-zone feeders, and bottom feeders) so they do not compete with each other for food.
10. What common errors do students make when solving questions on animal husbandry from Chapter 12?
A common error is confusing the specific management needs of different types of livestock. For example, students might mix up the dietary requirements for broilers (protein-rich food for fast growth) and layers (calcium-rich food for egg production). Another pitfall is providing a generic answer for "management practices" without specifying differences in shelter, feed, and disease prevention for dairy cattle versus poultry, as detailed in the NCERT solutions for the 2025-26 syllabus.
11. How do NCERT solutions explain the process of improving cattle breeds, and which method is preferred?
The solutions explain that cattle breeds are improved to enhance milk production (in milch animals) and draught labour capacity (in draught animals). The most common method for improvement is selective breeding through cross-breeding. This involves mating an indigenous breed, known for its disease resistance (e.g., Red Sindhi), with an exotic breed, known for its long lactation period (e.g., Jersey or Brown Swiss), to produce offspring with a combination of both desirable qualities.
12. According to the NCERT solutions, what are the primary factors responsible for the loss of grains during storage?
The solutions categorise the factors into two groups:
- Biotic factors: These include damage caused by living organisms such as insects, rodents, fungi, mites, and bacteria that infest and consume the stored grains.
- Abiotic factors: These refer to non-living conditions, primarily inappropriate levels of moisture and temperature in the storage place, which can promote the growth of mould and lead to spoilage or germination.

















