Chapter 15 . Improvement in Food Resources

Class 9 Science Chapter 15 : Improvement in Food Resources Internal Questions and Answers

Internal Questions :

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

Answer: Cereals provide carbohydrates and fiber.

Pulses offer protein and dietary fiber.

Fruits provide vitamins, minerals, and antioxidants.

Vegetables offer various vitamins, minerals, and fiber.

Internal Questions :

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

Answer: Biotic factors, such as diseases , insects and nematodes from other organisms, can negatively impact crop production.

Abiotic factors, such as  drought , salinity , water , logging , heat , cold and frost , also influence crop growth and productivity.

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

Answer:  The desirable agronomic characteristics for crop improvements are :

(i) Tallness and profuse branching are desirable characters for fodder crops .

(ii) Dwarfness is desired in cereals, so that less nutrients are consumed by these crops .

Thus developing varieties of desired agronomic characters help give higher productivity .

Internal Questions :

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

Answer : Nutrients are supplied to plants by air, water and soil. There are several nutrients which are essential for plants. Air supplies carbon and oxygen, hydrogen comes from water, and soil supplies the other thirteen nutrients to plants. Amongst these, some are required in large quantities and are therefore called macro-nutrients. The other nutrients are used by plants in small quantities and are therefore called micro-nutrients .

2. How do plants get nutrients?

Answer : We need food for development, growth, and well-being. Similarly, plants also require nutrients for growth. Nutrients are supplied to plants by air, water, and soil. There are several nutrients that are essential for plants. Air supplies carbon and oxygen, hydrogen comes from water, and soil supplies the other thirteen nutrients to plants.

Internal Questions :

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

Answer: Manure : Manure contains large quantities of organic matter and also supplies small quantities of nutrients to the soil. Manure is prepared by the decomposition of animal excreta and plant waste. Manure helps in enriching soil with nutrients and organic matter and increasing soil fertility.

Fertilizer :  Fertilizers are commercially produced plant nutrients. Fertilizers supply nitrogen, phosphorus and potassium. They are used to ensure good vegetative growth (leaves, branches and flowers), giving rise to healthy plants. Fertilizers are a factor in the higher yields of high-cost farming.

Internal Questions :

1. 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.

Answer: (c) Farmers using quality seeds, adopting irrigation, using fertilizer, and employing crop protection measures will likely provide the most benefits. This combination ensures improved genetic traits, sufficient water supply, optimal nutrient availability, and protection against pests and diseases, resulting in enhanced crop yield, quality, and overall productivity.

Internal Questions :

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

Answer : In warehouses and storage, preventive measures and biological control methods should be preferred for crop protection because they help maintain the quality of stored crops without relying on chemical pesticides. Proper drying and storage conditions, along with biological controls, reduce the need for chemical pesticides, ensuring safe and healthy food storage.
2. What factors may be responsible for losses of grains during storage?

Answer : The factors be responsible for losses of grains during storage are :

(i)  Biotic :  insects, rodents, fungi, mites and bacteria, and

(ii) Abiotic :  inappropriate moisture and temperatures in the place of storage.

These factors cause degradation in quality, loss in weight, poor germinability, discolouration of produce, all leading to poor marketability .

Internal Questions :

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

Answer : Crossbreeding is commonly used to improve cattle breeds because it combines the desirable traits of exotic or foreign breeds with local breeds, resulting in crossbreeds that often exhibit better productivity, disease resistance, and adaptability to local conditions .

Internal Questions :

1. 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 highlights the efficiency of poultry in converting low-fiber, non-human-consumable food into nutritious animal protein. This is significant for food production, as it allows the utilization of resources that might otherwise go to waste. Poultry farming can contribute to food security and provide a sustainable source of protein, making it a valuable component of India's agriculture and nutrition strategies.

Internal Questions :

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

Answer : Common management practices in dairy and poultry farming  are :

Feeding: Providing balanced nutrition to animals for optimal growth and milk/egg production.

Health Care: Regular vaccinations and healthcare to prevent diseases.

Hygiene: Maintaining clean and sanitary conditions for animals and their living spaces.

Breeding: Selecting and breeding animals for desirable traits.

Housing: Providing suitable shelters and facilities for animals.

Record-keeping: Maintaining records of animal health, production, and breeding.

Marketing: Selling dairy products or eggs in the market.

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

Answer:  The main differences in broilers and layers and their management:

Aspect	Broilers	Layers
Purpose	Raised for meat production	Raised for egg production
Diet	High-protein for growth	Balanced diet with calcium
Housing	Open or confinement houses	Need nesting boxes
Lighting	Extended light for eating	Specific lighting schedules
Management Focus	Growth and weight gain	Egg quality and quantity

Internal Questions :

1. How are fish obtained?

Answer : Fish are obtained through fish farming in controlled environments like fish farms or using natural resources such as oceans, rivers, lakes, and ponds. In fish farming, fish are raised in tanks or ponds, while natural resource-based fishing involves catching fish using methods like nets, lines with hooks, and traps from natural water bodies.
2. What are the advantages of composite fish culture?

Answer: The advantages of composite fish culture include increased fish production and income due to the simultaneous culture of multiple fish species in the same pond. This approach optimizes resource utilization, reduces disease risk, and enhances pond ecosystem stability, leading to better overall productivity and profitability in aquaculture.

Internal Questions :

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

Answer: The desirable characters of bee varieties for honey production are:

(i) High honey collection capacity.

(ii) Long foraging periods.

(iii) Good breeding capabilities.

(iv) Adaptability to available flower sources.
2. What is pasturage and how is it related to honey production?

Answer: Pasturage refers to the availability of flowering plants or forage in an area where bees can collect nectar and pollen. The value and quality of honey depend on pasturage because the types of flowers available to bees influence the taste of the honey. Adequate quantity and diversity of pasturage are essential for bees to produce high-quality honey.

Class 9 Science Chapter 15 : Improvement in Food Resources Exercise Questions and Answers

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

Answer : One method of crop production that ensures high yield is hybridization. In this approach, crop varieties with desirable characteristics, such as disease resistance, high yields, and quality, are developed by crossing genetically dissimilar plants. This can be done intervarietally (between different varieties), interspecifically (between two different species of the same genus), or intergenerically (between different genera). Hybridization helps combine the best traits from different plants to create new varieties that produce higher yields and improved qualities.
2. Why are manure and fertilizers used in fields?

Answer: Manure and fertilizers are used in fields for the following reasons:

(i) Manure helps enrich the soil with nutrients and organic matter, increasing soil fertility.

(ii) Fertilizers supply nitrogen, phosphorus, and potassium, ensuring good vegetative growth (leaves, branches, and flowers) and promoting the health of plants.
3. What are the advantages of inter-cropping and crop rotation?

Answer :  The advantages of Inter-Cropping are :

(i) Different crops grown together can utilize resources more efficiently, leading to higher overall yields.

(ii) Some combinations deter pests, reducing the need for pesticides.

(iii) Diverse crops can utilize nutrients in the soil more effectively.

(iv) If one crop fails, the other may still thrive, reducing the risk of total crop loss.

The advantages of Crop Rotation are :

(i) Rotating crops can break disease cycles, lowering the risk of soil-borne diseases.

(ii) Different crops require varying weed control methods, reducing weed pressure.

(iii) Crop rotation helps maintain soil fertility and structure.

(iv) Different crops have different nutrient needs, promoting efficient nutrient cycling .

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

Answer : Genetic manipulation, also known as genetic engineering, is the process of altering an organism's DNA to introduce specific traits or characteristics.

Usefulness in Agricultural Practices are :

(i) Genetic manipulation is used to create crops with desired traits.

(ii) Crops can be engineered to resist pests, reducing the need for pesticides.

(iii) Genetically modified crops can withstand water scarcity.

(iv) It helps enhance crop productivity.

(v) Essential nutrients can be added to crops.

(vi) Genetic manipulation contributes to more sustainable agriculture.

5. How do storage grain losses occur?

Answer : The storage grain losses occur due to various factors are :

(i) Biotic factors : insects, rodents, fungi, mites and bacteria, and

(ii) Abiotic factors : inappropriate moisture and temperatures in the place of storage.

6. How do good animal husbandry practices benefit farmers?

Answer :  Good animal husbandry practices benefit farmers in several ways are : 

(i) Proper care keeps animals healthy and reduces the risk of diseases.

 (ii) Healthy animals produce more meat, milk, or other products.

 (iii) Fewer medical expenses and efficient resource use result in cost savings.

 (iv) Improved animal well-being leads to higher income for farmers.

 (v) Good practices build trust with consumers and enhance the farm's reputation.

 (vi) Sustainable practices ensure long-term farm success.

7. What are the benefits of cattle farming ?

Answer:  The benefits of cattle farming are:

(i) Cattle are raised for beef, which is a valuable source of protein.

 (ii) Dairy cattle provide milk and dairy products.

 (iii) Cattle produce valuable manure for fertilizing crops.

 (iv) Cattle farming can be a source of income for farmers through sales of meat, milk, and calves.

 (v) It creates jobs in the agricultural sector.

 (vi) Cattle also provide by-products like leather and hides.

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

Answer: The common factor in poultry, fisheries, and bee-keeping for increasing production is cross breeding .
9. How do you differentiate between capture fishing, mariculture and aquaculture?

Answer:  The difference between capture fishing, mariculture and aquaculture are :

Aspect	Capture Fishing	Mariculture	Aquaculture
Method	Catching fish in natural habitats using nets, lines, traps, etc.	Cultivating marine organisms in enclosed or semi-enclosed areas in coastal waters or open seas	Cultivating aquatic organisms in controlled environments such as tanks or ponds
Location	Oceans, rivers, lakes, or other natural bodies of water	Coastal waters or open seas	Tanks, ponds, or controlled systems
Focus	Catching fish from wild populations	Raising marine species in controlled environments	Farming a wide range of aquatic organisms
Control	No direct control over the growth or reproduction of fish	Some control over the growth and reproduction of marine organisms	High level of control over the growth and reproduction of aquatic organisms
Environmental Impact	Can potentially impact wild fish populations and ecosystems	Can have localized environmental impacts near mariculture sites	Environmental impacts can be managed and mitigated with proper practices
Scope	Dependent on availability and migration patterns of wild fish populations	Primarily focuses on marine species	Covers both marine and freshwater species