CBSE Class 9 Biology Natural Resources Worksheet

Question. Give brief sketch on advantages and disadvantages on manure and fertilizers.
Answer: Advantages of manure :
(i) It increases the number of friendly microbes.
(ii) It improves the texture of soil by adding organic matter (humus).
(iii) It increases soil fertility, water holding capacity and aeration.
(iv) It reduces soil erosion.
(v) It is cheap.
Disadvantages of manure :
(i) They have fewer amounts of nutrients as compared to fertilizers.
(ii) Manures are bulky and not easy to store and transport.
Fertilizers : These are commercially manufactured inorganic salts containing one or more essential plant nutrients like NPK, which are used to increase soil fertility.
Advantages of fertilizers :
(i) They are nutrient specific and required in small amounts.
(ii) They are water soluble and absorbed by the plant easily.
(iii) They are easy to store and transport. Disadvantages of fertilizers :
(i) Fertilizers can change the soil structure by killing the soil microbes.
(ii) Fertilizers can change the chemical composition of soil.
(iii) Accumulation of fertilizers in water bodies causes eutrophication.

Question. What are the main characters required in a crop during its improvement practices?
Answer:
The useful characters that are required in a crop during its improvement :
(i) Disease resistance
(ii) Response to fertilizer
(iii) Product quality
(iv) High yield
(iii) Intergeneric – between two different genera

Question. What are the main characters required in a crop during its improvement practices?
Answer: The useful characters that are required in a crop during its improvement :
(i) Disease resistance
(ii) Response to fertilizer
(iii) Product quality
(iv) High yield

Question. Give difference between apiculture and aquaculture.
Answer: Domestication of honeybees or production of honey and wax on commercial bases is called apiculture. Farming and management of fish and other aquatic animals and plants in water is called aquaculture.

Question. What are fertilizers? Excess use of fertilizers is not advisable, explain.
Answer: Fertilizers are commercially produced plant nutrients. They supply nitrogen, phosphorus and potassium. hey are used to ensure good vegetative growth, giving rise to healthy plants.
Excessive use of fertilizers are not advisable as:
(a) It leads to soil and water pollution.
(b) It can destroy the fertility of soil.

Question. Why there is necessity of animal husbandry?
Answer: To fulfil growing demand for milk, eggs and meat and providing self employment livestock production is needed.

Question. What factors may be responsible for losses of grains during storage? Also mention any two preventive measures to control loss of grains during storage.
Answer: Factors responsible for losses are :
Biotic : Insects, rodents, fungi, mites and bacteria.
Abiotic : Inappropriate moisture and temperatures in the place of storage. Cleaning of the produce before storage, proper drying of the produce first in sunlight and then in shade, and fumigation are preventive measures to control loss of grains during storage.

Question. What are the various methods of irrigation in India?
Answer: Most of agriculture in India is rain-fed, several different kinds of irrigation system are adopted to supply water to agricultural lands. The resources are-wells, canals,rivers and tanks.
(i) Wells : Dug wells and tube wells. In dug wells water is collected from water— bearing strata.
(ii) Tubewells : Water from deeper strata.
(iii) Canals : Most extensive irrigation system. Canals receive water from reservoirs or rivers. The main canal is divided into branch canals having further distributaries to irrigate fields.
(iv) River lift system : Water is directly drawn from the river for supplementing irrigation in areas close to rivers.
(v) Tanks : These are small storage reservoirs, which intercept and store the run-off of smaller catchment areas.

Question. What are the factors for which variety improvement of crop is done?
Answer: (a) Higher yield : It increases production of crop.
(b) Biotic and abiotic resistance : Crop should be resistant to biotic factors like diseases, insects, pests and abiotic factors like drought, salinity, heat, etc.
(c) Change in maturity duration : Short-duration maturity allows farmer to grow more crops in a year with short duration maturity and reduces the crop production cost.
(d) Wider adaptability : Crop should be able to adapt to changing environmental conditions.
(e) Desirable agronomic characteristics : Crop should have tallness and dwarfness as per need. Dwarfness is required for cereals, so that few nutrients are consumed.

Question. Write a paragraph in your own words on each of the following.
(a) Preparation of soil,
(b) Sowing,
(c) Weeding,
(d) Threshing
Answer: 
(a) Preparation of soil : Preparation of soil is the first step of farming. Soil is loosened and turned over. This helps in making the soil more airy so that roots can breathe in air. Moreover, loosening of soil also facilitates better penetration of roots into the soil. Seeds can be easily sown in loosened soil.
(b) Sowing : The method of putting the seeds into soil is called sowing. Traditionally, seed is sown manually by spreading the seeds by hands. This process is called broadcasting. Seed drills are used when sowing needs to be done on a large scale.
(c) Weeding : Removal of weeds is called weeding. Unwanted plants which grow along with the crop are called weeds. They compete for resources; like sunlight, water and air; with the main crop. So, it is necessary to remove weeds for proper growth ofcrops. Weeding is usually done manually by using  hands and sickles. Sometimes weedicides are also sprayed.
(d) Threshing : Separation of grains from harvested stems is called threshing. For smaller quantity, threshing is done by hands. For somewhat bigger quantity, threshing is done using animal; especially bullocks. Animals are made to trample over the harvested stock which helps in separation of grains. Threshing machines are used for bigger  quantities.

Question. What is the advantage of composite fish culture?
Answer: The composition of six species of fish in composite fish is highly advantageous because:
(i) These fishes do not compete for food among themselves
(ii) They have different food habit
(iii) Food in all parts of pond is utilized due to different food habits

Question. Why Apis mellifera is adopted for domestication to produce honey?
Answer: The Italian species of honey bee, i.e. Apis mellifera is adopted for its many good qualities. They :
(i) sting less
(ii) have good honey collection capacity
(iii) produce with less swarming
(iv) have ability to protect itself from enemy
(v) stay in beehives for a long time

Question. “Shorter the duration of the crop from sowing to harvesting, the more economical is the variety.” Give reason for this.
Answer: Farmers can grow more crops in a year due to short duration of crop growth, and reduce the cost of crop production.

Question. Name different types of crop production practices involved in India.
Answer: They are (a) no cost production, (b) low cost production and (c) high cost production.

Question. Name the nutrients that plant obtains from air and water.
Answer: Air - Carbon and oxygen
        Water - Hydrogen and oxygen

Question. Name the products obtained from apiculture.
Answer: Honey and wax both are obtained from apiculture.

Question. What is meant by bee-keeping?
Answer: Rearing of bees for the production of honey on a large scale is called bee-rearing.

Question. Name two exotic breeds of cattle.
Answer: Jersey and Brown Swiss

Question. What are the practices used for dairy industry?
Answer: The practices used for dairy industry to get the optimum yield are :
(i) Shelter : The shelter should be clean, spacious and airy.
(ii) Feeding : Proper food at proper time is essential for dairy animals.
(iii) Rearing of animals : Providing them proper health care and protection from pathogens, diseases and proper vaccination.
(iv) Breeding : The crossing of different variety of milch animals to obtain a breed that can produce more yield of milk.

Question. Large amount of food grains get spoiled every year in India due to improper storage of food grains. How can this be avoided?
Answer: Food grains get spoiled by insects, fungi, rodents, bacteria, moisture at the place of storage. Storage losses can be reduced by taking some preventive and control measures.
(i) The seeds that are to be stored should be dry
(ii) The grains should be cleaned
(iii) The grains should be fumigated using chemicals that kills pest.
(iv) The storage houses should be waterproof.
(v) The grains should be stored in sealed gunny bags.
(vi) The bags should be kept few centimetres away from the wall.
(vii) The walls and the floor should be water-proof with no holes in it, to avoid rodents, pests.

Question. What are weeds? How can we control them? Give different methods of weed control.
Answer: Unwanted plants which grow along with crops are called weeds. Weeds compete with crops for natural resources; like sunlight, water and nutrients. Thus, weeds hamper the growth of crops. Weeds are usually removed manually by hands and by sickles. This process is called weeding. Sometimes, weedicides are also sprayed to kills weeds. Weeds can be controlled by different methods :
(a) Weedicides : These are the chemicals sprayed on the weeds to kill them. Excessive use is poisonous and causes environmental pollution.
(b) Mechanical removal : In this method weeds are uprooted by removing manually or by machines.
(c) Preventive methods : Proper seed bed preparation, timely sowing of crops, intercropping and crop rotation helps in weed control.

Question. Explain different types of fisheries.
Answer: The different types of fisheries are marine fisheries; inland fisheries, capture fishing, mariculture and aquaculture.
(i) Marine fisheries : Marine fishes are caught using fishing nets.
(ii) Mariculture : Marine .fishes are cultured in seawater.
(iii) Inland fisheries : The fisheries done in freshwater resources like canals, ponds, reservoirs and rivers.
(iv) Capture fishing : It is done in sea-water, estuaries and lagoons.
(v) Aquaculture : Culture of fish done in different water bodies is called aquaculture.

Question. Explain how soil gets affected by the continuous plantation of crops in a field.
Answer: Continuous plantation of crops in a field affects soil fertility. Plants utilize all the nutrients from soil which leads to depletion of nutrients in the soil. As a result, soil fertility reduces drastically.

Question. A group of gardening club students prepared a  kitchen garden in the school campus and did organic farming to grow the vegetables. Then the students presented their group work in the assembly to spread the awareness and make students understand the importance of organic products.
(a) What is horticulture?
(b) What is green manure?
Answer: (a) Hotriculture is the commercial production of vegetables and fruits.
(b) The green plants like sun hemp are turned into the soil which enriches the soil with nitrogen and phosphorus and is called green manure.

Question. What are the three advantages of shorter duration of the crop in between sowing and harvesting?
Answer: Short durations allow farmers to grow multiple rounds of crops in a year. Short duration also reduces the cost of crop production. Uniform maturity makes the harvesting process easy and reduces losses during harvesting.

Question. Which nutrients are supplied by cereals and pulses?
Answer: Carbohydrate is supplied by cereals and protein is supplied by pulses.

Question. Define animal husbandry.
Answer: Animal husbandry is the management and care of farm animals by humans for profit.

Question. Name two factors responsible for wastage of grains during storage.
Answer: Factors responsible for such losses are :
Biotic : insects, rodents, fungi, mites and bacteria,
Abiotic : inappropriate moisture and temperatures in the place of storage.

Question. (i) Name an exotic variety of honey bee grown in India.
(ii) What is called the rearing of fish on a large scale?
Answer:
(i) Apis cerana indica
(ii) Pisciculture

Question. Is breeding and rearing of Bombay duck part of poultry farming or a part of pisciculture?
Answer: It is a part of pisciculture as Bombay duck is fish not a duck.

Question. What is the tremendous increase in the production of eggs in India known as?
Answer: Golden revolution and Silver revolution.

Question. State the preventive and control measures used before grains are stored.
Answer:
(i) Cleaning of the grains.
(ii) Keep seeds in sunlight to provide moisture.
(iii) Using chemicals that kills pest.

Question. Environment is controlled by
(A) matter
(B) energy
(C) both
(D) only (2) is correct

Answer: C

Question. The strata near to earth is
(A) Thermosphere
(B) Stratosphere
(C) Mesosphere
(D) Troposphere

Answer: D

Question. The agent/s which make/s free atmospheric nitrogen available to plants is / are
(A) lightning
(B) free living nitrogen fixing bacteria
(C) symbiotic nitrogen fixing bacteria
(D) all of these

Answer: D

Question. Earth is protected from dangerous UV radiations by
(A) Oxygen layer
(B) CO₂ layer
(C) Ozone layer
(D) Photochemical smong layer

Answer: C

Question. The environmental equilibrium is restored by
(A) producers
(B) decomposers
(C) consumers
(D) top consumers

Answer: B

Question. What is true for earth ?
(A) Earth is an open system as it receives energy
(B) Earth is a closed system as it does not take any new matter
(C) Both (1) and (2)
(D) Neither (1) nor (2)

Answer: C

Question. In sedimentary cycles, the reserve pool is
(A) air
(B) water
(C) lithosphere
(D) lithosphere and atmosphere

Answer: C

Question. Layer of ozone is present in
(A) Stratosphere
(B) Thermosphere
(C) Mesosphere
(D) Troposphere

Answer: A

Question. Land forms ______ part of earth surface
(A) 30%
(B) 36%
(C) 50%
(D) 70%

Answer: A

Question. The process of evapo-transpiration and precipitation is known as
(A) carbon cycle
(B) hydrological cycle
(C) nitrogen cycle
(D) all of these

Answer: B

Question. Composition of air remains unchanged
(A) above height of 80 km
(B) below height of 60 km
(C) below height of 80 km
(D) none of these

Answer: C

Question. Match the following
1. Matter and energy (a) Environment
2. Atmospheric vapour (b) Living crust
3. Annual precipitation (c) 4.46 × 10²⁰
4. Biosphere (d) λ 0.15 – 4µ
5. Solar radiation (e) 0.13 × 1020 G
(A) 1 (a) 2 (b) 3 (c) 4 (d) 5 (e)
(B) 1 (a) 2 (e) 3 (c) 4 (b) 5 (d)
(C) 1 (b) 2 (a) 3 (c) 4 (d) 5 (e)
(D) 1 (b) 2 (c) 3 (e) 4 (a) 5 (d)

Answer: B

Question. Match the following
1. sedimentary cycle (a) Gaseous cycle
2. water (b) soil
3. atmospheric nitrogen fixation (c) 140 – 700 mg / m² / year
4. biological nitrogen fixation (d) 35 mg / m² / year
5. biogenetic nutrients (e) essential exhaustible
(A) 1 (b) 2 (a) 3 (d) 4 (c) 5 (e)
(B) 1 (b) 2 (e) 3 (c) 4 (d) 5 (a)
(C) 1 (b) 2 (e) 3 (c) 4 (d) 5 (a)
(D) 1 (b) 2 (a) 3 (e) 4 (d) 5 (c)

Answer: A

Question. Study of Biogeochemical cycles is called Biogeochemistry. Its father is Vernadsky (= Winodgsky). It involves
(A) cycling of energy
(B) cycling of gases
(C) cycling of nutrients
(D) cycling of water

Answer: C

Question. The peak concentration of ozone above surface of earth is at
(A) 25 km
(B) 15 km
(C) 60 km
(D) 40 km

Answer: A

Question. Name two kharif crops.
Ans : Paddy and soyabean.

Question. Name two rabi crops.
Ans : Wheat and gram.

Question. Explain how fertilisers are different from manure.
Ans : Fertilisers are synthesized in factories from inorganic materials. On the other hand, manure is made from organic materials; through the process of decomposition. Excessive use of fertilisers is not good for soil and may lead to soil pollution. Use of manure is beneficial for soil.

Question. Name any three methods of irrigation and briefly describe them.
Ans : (a) Drip irrigation : In this kind of irrigation, water is supplied drop by drop near the roots of the crops or plants. They is generally used in the areas where there is a scarcity of water. However, it is very expensive.
(b) Sprinkler system : In this system, the water escapes from the revolving nozzles and is sprinkled like rain on the crops. This system is used for sandy soils and uneven land.
(c) Surface irrigation : Method to supply water to agricultural lands from well, river, dam, etc.

Question. What is mariculture?
Ans : The culture of marine fish in sea water is called mariculture.

Question. What are macro-nutrients?
Ans : The nutrients required by plants in larger quantity is called macro-nutrients. They are nitrogen, phosphorus, potassium, calcium, magnesium and sulphur.

Question. State the meaning of capture fishing and culture fishing.
Ans : Capture fishing : It is done from natural resources. Culture fishing : It is done by fish farming.

Question. Name four marine fish varieties.
Ans : Pomphret, mackerel, tuna and sardines.

Question. From where do plants get nutrients?
Ans : Air, water and soil provides nutrients to plants.

Question. Differentiate between milch and draught animals.
Ans : Milk producing animals are called mulch animals. Animals used for farm labour are called draught animals.

Question. Why should weeds be constantly removed from cultivated fields?
Ans : Weeds take up nutrients and reduce the growth of the crop.

Question. What is meant by bee-keeping? Name : (a) the variety commonly used for commercial honey production. (b) the variety having high honey collection capacity.
State how pasturage is related to honey production.
Ans : Beekeeping is the practice of rearing bee for making honey (a) Indian bee (Apis ceranaindica), (b) The Italian (Apis mellifera) bees have high honey collectioncapacity. Pasturage is the availability of flowers to the bees for nectar and pollen collection. Pasturage is related to honey production because it determines the taste of honey and the quantity of honey.

Question. Why do we eat pea and groundnut?
Ans : Pea (matar) provides us protein whereas groundnut provide us necessary fats.

Question. Mention two examples of mixed cropping.
Ans : Some combinations of mixed cropping are : wheat and mustard, groundnut and sunflower.

Question. Write four methods of weed control.
Ans : Spraying weedicide, mechanical removal, sowing of crops, intercropping and crop rotation also help in weed-control.

Question. State one importance of photoperiod in agriculture.
Ans : Photoperiod in agriculture provide adequate light for flowering.

Question. Name one micronutrient and one macronutrient which plants take from the soil.
Ans : Macronutrients are : Calcium (Ca), Magnesium (Mg) and Micronutrients are : Boron (B), Chlorine (Cl).

Question. Name the two vitamins which are added in the poultry feed.
Ans : Vitamins A and K.

Question. Organism which enriches the soil with nutrients is called biofertilizers.
(a) Write its advantage. (b) Give example.
Ans : (a) Biofertilizers are non-pollutant sources of plant nutrients. They are renewable.
(b) Example of biofertilizers are- Rhizobium, Blue green algae.

Question. A group of Science Club students made a compost pit in the school, they collected all bio-degradable waste from the school canteen and used it to prepare the compost.
(a) Name, two waste that can be used for the compost and two wastes obtained from canteen which cannot be used for the compost making.
(b) What is the other important component required for making the compost?
Ans : (a) Two waste used for compost are vegetable peels and fruit peels. Two waste materials that cannot be used as compost are polythene bags and plastic items.
(b) Bacteria and fungi present in soil are the other important component for making compost.

Question. From where do plants acquire the following nutrients?
(a) Nitrogen, (b) Hydrogen.
Ans :
(a) Nitrogen from soil,
(b) Hydrogen from waste.

Question. Name the cereals which provide us carbohydrate for energy requirement.
Ans : Cereals such as wheat, rice, maize, millets and sorghum provide us carbohydrate for energy requirement.

Question. Give technical term for milk producing females and farm labour animals.
Ans : Milk-producing females are called milch animals (dairy animals), while the ones used for farm labour are called draught animals.

Question. List two desirable traits for fodder crops.
Ans : Tallness and profused branching are the desired characteristics for producing a higher yield of fodder crops.

Question. What are the major group of activities involved for improving of crop yields?
Ans :
(i) Crop variety improvement
(ii) Crop production improvement
(iii) Crop protection improvement