Class 9 Science Chapter 12 Question Answers - Improvement in Food Resources

Q1: How do biotic and abiotic factors affect crop production?
Ans: Living organisms such as honey bees and earthworms aid improve crop output, whereas pests (insects and rodents) and bacteria have a negative impact on crop production.
Climate conditions and nonliving natural resources such as soil, water, and air are examples of abiotic factors.They also have an impact on crop productivity, as favourable temperature, humidity, and mineral nutrition boost crop yield.

Q2: What are the desirable agronomic characteristics for crop improvements?
Ans:The following are desired agronomic traits for crop improvement:
(i) For cereal crops, dwarfness is a beneficial trait since it allows the plants to use fewer nutrients.
(ii) Tallness and profuse branching are ideal traits for fodder crops so that we can get more leaves to feed our animals.

Q3: What are macronutrients and why are they called macronutrients?
Ans: There are sixteen nutrients that are required for plant growth. Six of these thirteen nutrients are considered macronutrients since they are required in high amounts.
Nitrogen, phosphorus, potassium, calcium, magnesium, and sulphur are all macronutrients.

Q4: How do plants get nutrients?
Ans: Plants get their nutrients from the air, water, and soil.Nutrients supplied as a source Carbon in the air, oxygen in the air Hydrogen and oxygen are found in water.
Soil nitrogen, phosphorus, potassium, calcium, magnesium, sulphur, iron, manganese, boron, zinc, copper, molybdenum, chlorine, zinc, manganese,

Q5: Why should preventive measures and biological control methods be preferred for protecting crops?
Ans: It is likewise true for plants that prevention is preferable to treatment. Herbicides, weedicides, insecticides, pesticides, fungicides, and other chemicals are sprayed on the crop.
Because their excessive usage can injure crop plants and pollute the environment, careful seed bed preparation, timely crop sowing, intercropping, and crop rotation are also recommended.

Q6: Which method is commonly used for improving cattle breeds and why?
Ans: Cross breeding is a typical technique for developing cow breeds.
For instance, in dairy animals Exotic or foreign breeds (such as Jersey and Brown Swiss) are bred for lengthy lactation durations, whilst native breeds (such as RedSindhi and Sahiwal) are bred for disease resistance. The two can be crossed to produce animals with both desirable traits.

Q7: 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: Under poultry the birds kept are fed on agricultural waste material and broken grains etc which are not useful for humans but those birds consuming such waste provide us with eggs and meat. It is highly nutritious animal protein food hence the statement made is quite appropriate.

Q8: What management practices are common in dairy and poultry farming?
Ans: Food requirements Proper cleaning and shelter facilities Protection from unfavourable climatic conditions and diseases are frequent management strategies in dairy and poultry farms. Protection against pests

Q9: How are fish obtained?
Ans: Fishes can be obtained in two ways.
(a) apture fishing: This is a method of collecting fish from natural sources (rivers, lakes, oceans).
(b) Cultural fishery: This is also known as fish farming and involves the rearing and breeding of selected fish.

Q10: What are the advantages of composite fish culture?
Ans:The following are some of the benefits of composite fish culture:

• In such systems, both indigenous and imported fish species can be utilised.
• Food accessible in all regions of the water reservoir is exploited due to the non-competitive nature of selected species.
• Increases the amount of fish in the water reservoir (intensive fish farming).

Q11: What are the desirable characters of bee varieties suitable for honey production?
Ans: Characteristics of bee types appropriate for honey production include:

• Honey harvesting capacity is high. They have to be less stingy.
• They should stay in a beehive for a long time and breed prolifically.

Q12: What is pasturage and how is it related to honey production?
Ans: Pasturage refers to the blooms that bees can collect nectar and pollen from. The pasturage determines the value or quality of honey. In addition, the type of flowers present will influence the honey's flavour.

Q13: For increasing production, what is common in poultry, fisheries and bee-keeping?
Ans: The following are steps that are commonly used in poultry, fisheries, and beekeeping to increase production:

• The best types and breeds are used. Food is supplied that is both nutritional and tasty.
• Cleanliness and hygienic conditions are maintained.

Q14:  What are the benefits of cattle farming?
Ans: Cattle farming provides two advantages:
(i) Draught animals for farm labour (males), i.e. tilling, irrigation, and carting.
(ii) Milch animals (dairy animals) are females who produce milk.

Q15: How do storage grain losses occur?
Ans: Storage grain losses are caused by a variety of biotic and abiotic factors: biotic factors include insects, rodents, bacteria, fungi, and other organisms that feed on grains. Unfavorable humidity and temperature conditions are abiotic variables.

Q16: Why are manure and fertilizers used in fields?
Ans: Manure contributes to soil fertility by supplementing it with nutrients and organic materials. The majority of organic matter in manure aids in soil structure improvement.
Fertilizers are used to promote healthy vegetative growth (leaves, branches, and flowers) by supplying specific nutrients such as nitrogen, phosphorus, and potassium.

Q17: Define
(a) Pisciculture 
Ans: Pisciculture is the large-scale rearing and management of fish.
(b) hatcheries
Ans: Hatcheries are nurseries where fish eggs or fish seed are placed in freshwater fisheries.
(c) swarming
Ans: Swarming is the process by which the new queen leaves the old hives and seeks out a new home for reproduction.

Q18:  What is green manuring? Give examples of green manures.
Ans: Green manure is made from herbaceous plants that are cultivated, ploughed beneath, and mixed with the soil while they are still green. Green manuring is the process of ploughing green plants and combining them with the soil.
Sun hemp, cluster bean (guar), lentil (Masur), and cowpea are some of the plants utilised as green manure (Lobia).

Q19: Discuss the preventive measures for the storage of grains.
Ans: The preventive measures for the storage of grains are:
(a) Drying - For grain storage, the moisture content of the grains should be decreased to less than 14 percent. This can be accomplished by drying in the sun and then drying in the shade.
(b) Hygiene should be maintained - Godowns and stores should be cleaned regularly.
Remove any dirt, trash, webs, or debris from the previously kept grains. Waterproofing and sealing cracks and gaps in the walls, floor, and ceiling are essential. For storing food grains, new gunny bags should be used. The mouth of the gunny bag should be tightly sewn once it has been filled.

Q20: Name three basic scientific approaches for increasing yield of a crop.
Ans: Three scientific approaches for increasing yields of a crop are –
(i) Crop production management, which involves correct irrigation and fertiliser management, is one of three scientific methodologies for enhancing crop yields. Manure and fertilisers can be used to accomplish this. Crop rotation, intercropping, and mixed-cropping can all help with nutrient management.Plants require protection from weeds, insects, pests, and pathogens.
(ii) Crop protection management It can be accomplished through biological, chemical, or cultural methods.
(iii) Crop variety management: Crop variety can be enhanced by hybridization or transgenic techniques. It is possible to do so in order to get desired plant traits

Q21: What are the advantages of bee-keeping?
Ans:The following are some of the benefits of beekeeping:
(a) It takes minimal investment and offers the farmer additional income.
(b) In addition to honey, beekeeping produces wax, royal jelly, and bee venom, among other things.
(c) Cross pollination is aided by bees.

Q22: Differentiate between capture fishing, aquaculture and mariculture.
Ans: 
(a) Capture fishing - Capture fishing is the process of obtaining fish from bodies of water such as rivers, seas, and oceans:
(b) Aquaculture - Aquaculture is the cultivation of aquatic creatures in fresh or saltwater.
(c) Mariculture - Mariculture is the cultivation of marine fish.

Q23: List the steps to be taken to prevent and control diseases in animals.
Ans: The following steps should be followed to control diseases:

• Providing adequate shelter.
• Maintaining animal hygiene and disposing of dead animals and animal wastes properly.
• Disease screening of animals on a regular basis, with unhealthy animals being isolated immediately.
• Following the advice of a veterinary practitioner, providing a proper diet and appropriate medications.
• Handling of all animal products and by product in a sanitary manner.

Q24: What are the components of cattle feed?
Ans: Roughage and concentrates are present in cattle feed in the form of hay and grain, as well as a large amount of water.

• Roughage — Roughage is made up of coarse and fibrous components with poor nutrient content; animals acquire roughage from hay (cereal straw) and grain, respectively, as well as a lot of water.
• Cotton seeds, oilseeds, oilcakes, and cereal grains like gramme and bajra are high in one or more nutrients (such as carbohydrate, lipids, proteins, minerals, and vitamins) and low in fibres. Cattle are fed green fodder in the winter, primarily Berseem and Lucerne, and maize, bajra, jowar, and dry fodder in the other seasons.

Q25: Define the following
(i) White revolution
Ans: The term "white revolution" refers to the increased production of milk. It required the utilisation of upgraded high-milk-yielding mulch animal crossbreeds.
(ii) silver revolution
Ans: The term "silver revolution" refers to a massive increase in egg output.
(iii) blue revolution.
Ans: The term "blue revolution" refers to an increase in fish production.

Q26: What is green manuring? Give an example of green manures?
Ans: Green manure is made from herbaceous plants that have been cultivated, ploughed under, and mixed with the soil while they are still green. Green manuring is the term for this process.
Sun hemp, cluster bean (guar), lentil (maser), and cowpea are some of the plants utilised as green manure (Berseem)

Q27: What are the main practices involved in keeping animals or animal husbandry?
Ans: Animal husbandry day involves the following main practises.

• Breeding - This is done to get animals with specific traits. Animals with high milk yields and meat yields can be developed through breeding.
• Feeding – This is the study of the right food (called feed), as well as the mode and timing of feeding of various animals.
• Weeding - This is the process of eliminating animals that are not economically viable.

Q28: Name the abiotic and biotic factors which affect stored grains and how?
Ans: Insects, birds, rodents, mites, fungi, and bacteria are examples of biotic forces.
(a) Moisture, temperature, and the storage container's material are all abiotic variables. As a result of the aforementioned conditions, cereal grains become infested with insects and microorganisms.
(b) Quality deterioration
(c) Weight reduction.
(b) Poor grain germination potential
(e) Produce discoloration

Q29: What is the need for crop improvement? What are the desirable agronomic characteristics for crop improvement?
Ans: Crop enhancement entails creating superior plants with the following characteristics:

• High-yielding
• Varieties with higher-quality produce.
• Disease-resistant cultivars
• Plants have beneficial agronomic traits, such as
  • Dwarfness is required in cereals, which consumes less nutrients.
  • Plants for fodder crops that are tall and have a lot of branching.

Q30: Define 
(i) Draught breeds
Ans: Draught cattle, sometimes known as bullocks, are cattle that are employed for labour.
(ii) Dual purpose breeds
Ans: Dual-purpose breeds are those that have females for milk and men for work.
(iii) Dairy breeds
Ans: Dairy animals are breeds that are solely used for milk production.

Q31: What are the symptoms of diseased animals?
Ans: 

• The animal stops eating and becomes lethargic, looks exhausted, and remains isolated as a result of the condition.
• The animal shivers as its body temperature rises.
• The animal produces an excessive amount of saliva, which hangs from its mouth at times.
• The animal excretes a mixture of loose dung and colourful urine.
• The animal's mouth and ears droop.

Q32: What do we get from cereals,pulses, fruits and vegetables?
Ans: Cereals provide carbohydrates, pulses provide proteins, while fruits and vegetables provide vitamins and minerals.

Q33: What factors may be responsible for losses of grains during storage?
Ans: Both biotic and abiotic factors may be responsible for losses of grains during storage are :

• Humidity and temperature of the environment and moisture content of grains are the abiotic factors.
• Biotic factors include organisms such as rodents, bacteria, fungi, and some insects that feed on grains.

Q34: What are weeds? Give two examples.
Ans: Weeds are undesired plants that grow in fields. Common weeds include Amaranthus and Chenopodium.

Q35: What is crop rotation?
Ans: Crop rotation is the technique of alternately cultivating various crops in the same land in a pre-planned succession.

Q36: What are drones?
Ans: Drones are airborne devices that are used in agriculture to improve crop output and to track crop growth.
They assist farmers in developing agricultural field systems for using water, fertilisers, herbicides, and seeds. These tools have revolutionised agriculture by allowing farmers to save significant amounts of money while also increasing efficiency and profitability.

Q37: What is pasturage and how is it important?
Ans: Crop rotation is the practise of farming a variety of crops in a pre- determined order on the same piece of land.

Q38: What is a layer and a broiler? What are the differences between the two?
Ans: The egg-laying poultry bird is known as an egg layer, whereas the meat-producing poultry bird is known as a chicken or broiler.
Housing (shelter), food, and environmental requirements differ from layer requirements. Broiler feed is protein- and vitamin-rich, with an acceptable fat content.

Q39: What are the characteristic features of ideal shelters for cattle?
Ans: The following are characteristics of a shelter:

• The animals are protected from rain, heat, and cold by a suitably roofed shed.
• The shed's floor is slanted to make cleaning easier and to keep their sitting area dry.
• A plan for safe drinking water is put in place.
• Excreta disposal is properly arranged in the sheds.

Q40: What are the hazards of using fertilizers?
Ans: Effects of fertiliser application –
(a) Impact on soil quality - fertiliser application leads to a loss of organic matter and a deterioration of soil structure.
(b) Eutrophication - Excessive fertiliser application causes nitrate buildup in the soil.
Rain washes nitrates and phosphates into lakes, ponds, and rivers, where they encourage algae to develop excessively.