NCERT Solutions for Class 12 Biology Chapter 9 Strategies for Enhancement in Food Production in Hindi Mediem
FAQs on NCERT Solutions for Class 12 Biology In Hindi Chapter 9 Strategies For Enhancement In Food Production In Hindi Mediem
1. How does animal husbandry contribute to human welfare, as per the NCERT Class 12 Biology syllabus for 2025-26?
According to the NCERT solutions for Chapter 9, animal husbandry plays a crucial role in human welfare by enhancing food production to meet the demands of a growing population. It is the agricultural practice of breeding and raising livestock like cattle, sheep, goats, and pigs, as well as poultry and fisheries. Its key contributions include:
- Dairy Products: Management of animals for milk and its products through dairying.
- Meat and Eggs: Poultry farming provides meat and eggs.
- Nutritional Supplements: Bee-keeping provides honey, a food of high nutritive value, and beeswax.
- Protein Source: Fisheries provide fish, a rich source of protein, and create employment for coastal communities.
- Other Products: Animals also provide other essential products like wool and silk.
2. What is the correct step-by-step method for a plant breeding program to develop a new crop variety?
The NCERT solution outlines a systematic five-step method for developing new crop varieties through plant breeding:
- Collection of Variability: The first step is collecting all wild varieties, species, and relatives of the cultivated species to gather all diverse alleles. This entire collection is known as the germplasm collection.
- Evaluation and Selection of Parents: The collected germplasm is evaluated to identify plants with desirable combinations of characters. These selected plants are then multiplied and used for the next step.
- Cross Hybridisation Among Selected Parents: The two selected parents with desired traits are cross-hybridised. For example, a high-protein quality parent is crossed with a disease-resistant parent to create a hybrid that combines both traits.
- Selection and Testing of Superior Recombinants: The resulting offspring (progeny) are screened for plants that have the desired combination of characters. This is a crucial step and requires careful scientific evaluation.
- Testing, Release, and Commercialisation: The newly selected lines are evaluated for their yield and other agronomic traits in research fields, and then in farmers' fields across different locations for at least three growing seasons. If the results are successful, the crop is released as a new cultivar.
3. To develop a virus-free plant, which part is most suitable for tissue culture and why is it the correct choice?
The most suitable part of a plant for preparing a virus-free specimen is the meristem (both apical and axillary). The reason for this, as explained in the NCERT solution, is that the meristematic tissues are in a state of continuous and rapid cell division. This high rate of division means the virus cannot multiply fast enough to infect the newly formed cells. Therefore, even if the parent plant is systemically infected with a virus, its meristem remains uninfected and can be used as an explant to grow a healthy, virus-free plant through tissue culture.
4. How does inbreeding depression occur in cattle, and what is the most effective method described in the NCERT solutions to overcome it?
Inbreeding depression occurs due to continued inbreeding, especially close inbreeding, over several generations. This practice increases homozygosity, which can lead to the expression of harmful recessive alleles that are otherwise masked by dominant alleles. The accumulation of these harmful traits results in reduced fertility and lower productivity in the cattle population. The most effective method to solve this problem, as per the NCERT solution, is a single out-cross. This involves mating the affected animal with an unrelated superior animal of the same breed. This introduces new genes into the population, restoring fertility and yield.
5. Beyond just increasing yield, how does the technique of biofortification address the global issue of “hidden hunger”?
Biofortification is a powerful solution to “hidden hunger,” which is a widespread deficiency of essential micronutrients like vitamins, minerals, and proteins in the diet. While traditional breeding focuses on increasing crop quantity (yield), biofortification aims to improve the nutritional quality of food crops. The NCERT solutions highlight how this is achieved:
- Increasing Protein Content: Developing wheat varieties like Atlas 66 with higher protein content.
- Enhancing Amino Acids: Creating maize hybrids with twice the amount of the amino acids lysine and tryptophan.
- Boosting Vitamin Levels: Developing vegetable crops like carrots and spinach that are enriched with Vitamin A.
- Improving Mineral Content: Breeding for crops with higher levels of minerals, such as iron-fortified rice, which can have five times more iron than conventional varieties.
By making staple foods more nutritious, biofortification directly combats micronutrient deficiencies in large populations.
6. What is the fundamental difference between a 'somaclone' and a 'somatic hybrid' in plant biotechnology?
The difference lies in their genetic makeup and the method of production:
- A somaclone is a plant produced through micropropagation (tissue culture) from a single parent plant. All somaclones are genetically identical to the parent plant and to each other. The primary objective is to produce a large number of uniform plants rapidly.
- A somatic hybrid is a plant created through somatic hybridisation. This involves taking single cells (protoplasts) from two different plant varieties, removing their cell walls, and fusing them together. The resulting hybrid cell contains genetic material from both parents and grows into a plant with a novel combination of traits that may not be possible through conventional sexual hybridisation.
7. Why is artificial insemination often considered a superior technique in animal breeding programs compared to natural mating?
Artificial insemination (AI) is often preferred over natural mating for several strategic reasons outlined in the CBSE syllabus. The key advantages that make it a superior method are:
- Overcoming Mating Issues: It helps overcome normal problems associated with mating and logistics of transporting animals.
- Widespread Use of Superior Males: Semen from a single, genetically superior male can be used to inseminate several females, even across different geographical locations.
- Long-term Storage: The collected semen can be frozen and stored for a long time in a 'semen bank', allowing its use even long after the male has died.
- Controlled Breeding: It ensures a controlled and planned breeding program, increasing the chances of desired offspring and improving the herd's genetic quality more efficiently.
8. What is the role of apiculture (bee-keeping) and fisheries in enhancing food production according to NCERT Chapter 9?
Both apiculture and fisheries are vital strategies for enhancing food production:
- Apiculture (Bee-keeping): This practice involves the maintenance of honeybee hives for producing honey and beeswax. Honey is a valuable, high-nutrition food and is also used in indigenous medicine. Importantly, bees are excellent pollinators. Placing hives in crop fields during the flowering season significantly increases pollination efficiency, leading to improved crop yields in addition to the honey harvest.
- Fisheries: This industry involves the catching, processing, and selling of fish, shellfish, and other aquatic animals. Fish are a crucial source of animal protein for a large part of the population. The Blue Revolution was initiated to increase production from both freshwater and marine sources, helping meet the rising demand for food and providing income and employment, especially in coastal areas.

















