CBSE Class 10 Biology Our Environment Worksheet Set B

Read and download free pdf of CBSE Class 10 Biology Our Environment Worksheet Set B. Download printable Science Class 10 Worksheets in pdf format, CBSE Class 10 Science Chapter 15 Our Environment Worksheet has been prepared as per the latest syllabus and exam pattern issued by CBSE, NCERT and KVS. Also download free pdf Science Class 10 Assignments and practice them daily to get better marks in tests and exams for Class 10. Free chapter wise worksheets with answers have been designed by Class 10 teachers as per latest examination pattern

Chapter 15 Our Environment Science Worksheet for Class 10

Class 10 Science students should refer to the following printable worksheet in Pdf in Class 10. This test paper with questions and solutions for Class 10 Science will be very useful for tests and exams and help you to score better marks

Class 10 Science Chapter 15 Our Environment Worksheet Pdf

MCQ Questions for NCERT Class 10 Science Our Environment

Question. What will be the result if in the following food chain goat population is decreased considerably?
Green plant→ goat→ Lion
(a) Green plants will die.
(b) The population of lion will increase.
(c) The population of green plants will increase and the lion population will decrease.
(d) Lion will start consuming green plants.

Answer : C

Question. Which of the following effects on humans will be caused by excessive exposure to UV-rays?
(a) Skin cancer
(b) Damage to immune system
(c) Damage to heart and lungs
(d) Peptic ulcers

Answer : A , B

Question. Which of the following represents an artificial ecosystem?
(a) Forest
(b) Grassland
(c) Lake
(d) Crop field

Answer : D

Question. Choose the correct statement(s).
(a) Green plants convert solar energy into chemical energy.
(b) Substances that are broken down by biological processes are nonbiodegradable.
(c) DDT and plastic are nonbiodegradable.
(d) Producers synthesize food from inorganic compounds.
Answer : A , C , D

Question. If a frog eats a grasshopper, then the energy will be transferred from
(a) consumer to producer
(b) primary consumer to secondary consumer
(c) secondary consumer to primary consumer
(d) secondary consumer to tertiary consumer

Answer : B

Question. Which of the following groups of organisms do notsynth esize carbohydrates from solar energy and inorganic compounds?
(a) Producer
(b) Herbivores
(c) Consumers
(d) Decomposers

Answer : B , C , D

Question. An ecosystem consists of
(a) nonliving things only
(b) living organisms only
(c) both living and nonliving things
(d) water, gases and soil

Answer : C

Question. Organisms which feed on dead plants and animals are called
(a) consumers
(b) producers
(c) decomposers
(d) heterotrophs

Answer : C

Question. Why should we not use plastic cups and plates?
(a) Because they are costly.
(b) Because they are biodegradable.
(c) Because they are very light.
(d) Because they are nonbiodegradable.

Answer : D

Question. Bacteria and fungi do not act as
(a) producers
(b) consumers
(c) autotrophs
(d) decomposers

Answer : A , B , C

Question. Which of the following groups of organisms convert organic materials to inorganic forms?
(a) Producers
(b) Consumers
(c) Decomposers
(d) Green plants

Answer : C

Question. The percentage of solar radiation absorbed by all the green plants for the process of photosynthesis is about :
(a) 1%.
(b) 5%.
(c) 8%.
(d) 10%. 

Answer : A

Question. Which one of the following green house gases is a contributor due to incomplete combustion of coal and petroleum?
(a) Oxides of nitrogen
(b) Methane
(c) Carbon monoxide
(d) Carbon dioxide

Answer : C

Question. What happens to the earth's temperature due to the greenhouse effect?
(a) Increases
(b) Decreases
(c) Remains the same
(d) All of the above 

Answer : A

Question. Select the mismatched pair in the following and correct it.
(a) Bio-magnification — Accumulation of chemicals at the successive trophic levels of a food chain
(b) Ecosystem — Biotic components of environment
(c) Aquarium — A man-made ecosystem
(d) Parasites — Organisms which obtain food from other living organisms 

Answer : B

Question. In the given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, what will be the energy available at the producer level? 
Grass → Grasshopper → Frog → Snake → Hawk
(a) 5 kJ
(b) 50 kJ
(c) 500 kJ
(d) 5,000 kJ 

Answer : D

Question. Organisms of a higher trophic level which feed on several types of organisms belonging to a lower trophic level constitute the ................... .
(a) Food web.
(b) Ecological pyramid.
(c) Ecosystem.
(d) Food chain. 

Answer : A

Question. Disposable plastic plates should not be used because
(a) They are made of materials with light weight.
(b) They are made of toxic materials.
(c) They are made of biodegradable materials.
(d) They are made of non-biodegradable materials.

Answer : D

Question. In a food chain, the third trophic level is always occupied by
(a) Carnivores.
(b) Herbivores.
(c) Decomposers.
(d) Producers. 

Answer : A

Question. Why is it difficult to degrade non-biodegradable wastes?
(a) Because non-biodegradable wastes cannot be recycled.
(b) Because microorganisms cannot decompose it.
(c) They can be made into organic wastes.
(d) All of the above 

Answer : B

Question. Excessive exposure of humans to UV-rays results in
(i) Damage to immune system.
(ii) Damage to lungs.
(iii) Skin cancer.
(iv) Peptic ulcers.
(a) (i) and (ii)
(b) (ii) and (iv)
(c) (i) and (iii)
(d) (iii) and (iv) 

Answer : C

Question. In an ecosystem, the 10% of energy available for transfer from one trophic level to the next is in the form of:
(a) Heat energy.
(b) Light energy.
(c) Chemical energy.
(d) Mechanical energy.

Answer : C

Question. Which one of the followings is an artificial ecosystem?
(a) Pond
(b) Crop field
(c) Lake
(d) Forest 

Answer : B

Question. Which of the followings are environment-friendly practices?
(a) Carrying cloth-bags to put purchases in while shopping.
(b) Switching off unnecessary lights and fans.
(c) Walking to school instead of getting your mother to drop you on her scooter.
(d) All of the above. 

Answer : D

Question. Which group of organisms are not constituents of a food chain?
(i) Grass, lion, rabbit, wolf
(ii) Plankton, man, fish, grasshopper
(iii) Wolf, grass, snake, tiger
(iv) Frog, snake, eagle, grass, grasshopper
(a) (i) and (iii)
(b) (iii) and (iv)
(c) (ii) and (iii)
(d) (i) and (iv) 

Answer : C

Question. Depletion of ozone is mainly due to _________.
(a) Chlorofluorocarbon compounds.
(b) Carbon monoxide.
(c) Methane.
(d) Pesticides. 

Answer : A

Question. Accumulation of non-biodegradable pesticides in the food chain in increasing amount at each higher trophic level is known as
(a) Eutrophication.
(b) Pollution.
(c) Biomagnification.
(d) Accumulation. 

Answer : C

Assertion and Reason Based MCQs :

Directions : In the following questions, A statement of Assertion (a) is followed by a statement of Reason (R). Mark the correct choice as.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is NOT the correct explanation of A.
(c) A is true but R is false.
(d) A is false and R is true.

Question. Assertion (a): Herbivores are called first order consumers.
Reason (R): Tiger is a top carnivore. 

Answer : B

Question. Assertion (a): Decomposers keep the environment clean.
Reason (R): They recycle matter by breaking down the organic remains and waste products of plants and animals. 

Answer : A

Question. Assertion (a): Wastes such as plastics, paper, vegetable or fruit peels, which are generated in our house daily are biodegradable.
Reason (R): Biodegradable wastes can be broken down into simpler, harmless substance in nature in due course of time by the biological processes such as action of microorganisms. 

Answer : D

Question. Assertion (a): Polythene bags and plastic containers are non-biodegradable substances.
Reason (R): They can be broken down by microorganisms in natural simple harmless substances. 

Answer : C.

Question. Assertion (a): Flow of energy in a food chain is unidirectional.
Reason (R): Energy captured by autotrophs does not revert back to the solar input and it passes to the herbivores. 

Answer : A

Question. Assertion (a): The concentration of harmful chemicals is more in human beings.
Reason (R): Man is at the apex of the food chain. 

Answer : A

Question. Assertion (a): Greater number of individuals are present in lower trophic levels.
Reason (R): The flow of energy is unidirectional.

Answer : B

Question. Assertion (a): First trophic level in a food chain is always a green plant.
Reason (R): Green plants are called producers. 

Answer : A

Question. Assertion (a): Ozone is both beneficial and damaging.
Reason (R): Stop the release of chlorofluorocarbons to protect the ozone. 

Answer : B

Question. Assertion (a): Food chain is responsible for the entry of harmful chemicals in our bodies.
Reason (R): The length and complexity of food chains vary greatly. 

Answer : B

Question. Assertion (a): CFCs deplete the ozone layer.
Reason (R): CFCs are used as refrigerants and in fire extinguishers. 

Answer : A

Case-based MCQs :

Read the following and answer the four questions given below :

Food chains are very important for the survival of most species. When only one element is removed from the food chain it can result in extinction of a species in some cases. The foundation of the food chain consists of primary producers.
Primary producers, or autotrophs, can use either solar energy or chemical energy to create complex organic compounds, whereas species at higher trophic levels cannot and so must consume producers or other life that itself consumes producers. Because the sun's light is necessary for photosynthesis, most life could not exist if the sun disappeared. Even so, it has recently been discovered that there are some forms of life, chemotrophs, that appear to gain all their metabolic energy from chemosynthesis driven by hydrothermal vents, thus showing that some life may not require solar energy to thrive.
CBSE Class 10 Biology Our Environment Worksheet Set B_1

Question. Mr. X is eating curd/yogurt. For this food intake in a food chain he should be considered as occupying:
(a) First trophic level
(b) Second trophic level
(c) Third trophic level
(d) Fourth trophic level

Answer : C

Question. The decomposers are not included in the food chain. The correct reason for the same is because decomposers:
(a) Act at every trophic level of the food chain
(b) Do not breakdown organic compounds
(c) Convert organic material to inorganic forms
(d) Release enzymes outside their body to convert organic material to inorganic forms

Answer : A

Question. If 10,000 J solar energy falls on green plants in a terrestrial ecosystem, what percentage of solar energy will be converted into food energy? 
(a) 10,000 J
(b) 100 J
(c) 1000 J
(d) It will depend on the type of the terrestrial plant.

Answer : B

Question. Matter and energy are two fundamental inputs of an ecosystem. Movement of
(a) Energy is bidirectional and matter is repeatedly circulating.
(b) Energy is repeatedly circulation and matter is unidirectional.
(c) Energy is unidirectional and matter is repeatedly circulating.
(d) Energy is multidirectional and matter is bidirectional.

Answer : C

Carefully study the given food web and answer the four questions given below :
CBSE Class 10 Biology Our Environment Worksheet Set B_2

Question. Why do all food chains start with plants?
(a) Because plants are easily grown.
(b) Because plants are nutritious.
(c) Because plants can produce its own energy.
(d) Because plants do not require energy.

Answer : C

Question. Which trophic level is incorrectly defined?
(a) Carnivores – secondary or tertiary consumers
(b) Decomposers – microbial heterotrophs
(c) Herbivores – primary consumers
(d) Omnivores – molds, yeast and mushrooms

Answer : D

Question. The given figure best represents:
CBSE Class 10 Biology Our Environment Worksheet Set B_3
(a) Grassland food chain
(b) Parasitic food chain
(c) Forest food chain
(d) Aquatic food chain

Answer : A

Question. In the food web, what two organism are competing for food?
CBSE Class 10 Biology Our Environment Worksheet Set B_4
(a) A and B
(b) A and C
(c) D and F
(d) B and D

Answer : D

Question. The mussel can be described as
(a) Producer
(b) Primary consumer
(c) Secondary consumer
(d) decomposer

Answer : C

Read the given passage and answer the questions given below :

Waste management is essential in today’s society. Due to an increase in population, the generation of waste is getting doubled day by day. Moreover, the increase in waste is affecting the lives of many people. 
Observe the following diagram and answer the questions any four from (i) to (v)
CBSE Class 10 Biology Our Environment Worksheet Set B_5
Waste management is the managing of waste by disposal and recycling of it. Moreover, waste management needs proper techniques keeping in mind the environmental situations. For instance, there are various methods and techniques by which the waste is disposed off. You must have come across 5 R’s to save the environment: refuse, reduce, reuse, repurpose and recycle.

Question. The given graph shows the amount of waste generated, dumped and treated in percentage.
Identify the reason of low success rate of waste management process.
CBSE Class 10 Biology Our Environment Worksheet Set B_7
(a) Only 15% of urban India’s waste is processed
(b) Less than 60% of waste is collected from households
(c) More than 60% of waste is collected from households
(d) Both (a) and (b)

Answer : D

Question. Recycling of paper is a good practice but recycled paper should not be used as food packaging because
(a) Recycled papers take lots of space.
(b) Recycled papers can’t cover food properly.
(c) Recycled papers can cause infection.
(d) Recycled papers are costly.

Answer : C

Question. Effective segregation of wastes at the point of generation is very important. Select the appropriate statements giving the importance of waste segregation.
(i) Less waste goes to the landfills
(ii) Better for public health and the environment
(iii) Help in reducing the waste
(iv) Resulting in deterioration of a waste picker’s health
(a) Both (i) and (ii)
(b) Both (i) and (iii)
(c) Both (ii) and (iii)
(d) Both (i) and (iv)

Answer : A

Question. Choose the waste management strategy that is matched with correct example.
(a) Refuse Choose products that use less packaging.
(b) Reduce Give unwanted toys and books to hospitals or schools.
(c) Reuse Not using single use plastic.
(d) Repurpose Making flower pot from used plastic bottle.

Answer : D

Question. According to the ‘Solid Waste Management Rule 2016’, the waste should be segregated into three categories.
Observe the table below and select the row that has correct information.
CBSE Class 10 Biology Our Environment Worksheet Set B_6

Answer : B

Read the following passage and answer the questions given below :

Human body is made up of five important components, of which water is the main component.
Food as well as potable water is essential for every human being. The food is obtained from plants through agriculture; Pesticides are being used extensively for a high yield in the fields. These pesticides are absorbed by the plants from the soil along with water and minerals and from the water bodies these pesticides are taken up by the aquatic animals and plants. As these chemicals are not biodegradable, they get accumulated progressively at each trophic level. The maximum concentration of these chemicals gets accumulated in our bodies and greatly affects the health of our mind and body.

Question. The maximum concentration of pesticides are found in
(a) Man
(b) Plants
(c) Deer
(d) Tiger

Answer : A

Question. With regard to various food chains operating in an ecosystem, man is a:
(a) Consumer
(b) Producer
(c) Producer and consumer
(d) Producer and decomposer

Answer : A

Question. Which of these methods could be applied to reduce our intake of pesticides through food to some extent ?
(a) Organic farming
(b) Mixed cropping
(c) Single cell protein
(d) Biofortification

Answer : A

Question. Various steps in a food chain represent:
(a) Food web
(b) Trophic level
(c) Ecosystem
(d) Bio-magnification

Answer : B

Based on the given information and your knowledge, answer the questions given below :

Food chains and the energy flow within an ecosystem provide an important understanding of contingencies and mutual dependencies of organisms.
The given below flow chart depicts the energy flow within some members of a grassland ecosystem. The grass in the below ecosystem transduces 120,000 J of sunlight and fixes it into 12,000 J of energy. It is established that 90% of the energy of one trophic level is not passed to the next trophic level. Further assume that the energy transferred from one trophic level to the next is equally shared among the different organisms at that trophic level.
CBSE Class 10 Biology Our Environment Worksheet Set B_8

Question. In the food web depicted above, identify the most energy efficient link for tertiary consumer.
(a) Rabbit
(b) Rat
(c) Lizard
(d) Grasshopper

Answer : A

Question. How many food chains are present in the food web depicted above?
(a) 2
(b) 3
(c) 5
(d) 6

Answer : C

Question. Based on the above information, indicate the amount of energy that an organism C may have received from an organism from the previous trophic level.
(a) 1,20,000 J
(b) 12, 000 J
(c) 1200 J
(d) 120 J

Answer : C

Question. Which organism acts as both the secondary consumer and the tertiary consumer?
(a) Snake
(b) Eagle
(c) Chicken
(d) Rat

Answer : B

Read the given passage and answer the questions given below :

A farmer is growing a crop regularly in his field. He uses chemical fertilizers, pesticides, organic manure as well as bio-fertilizers. Very close to his field is a factory which emits smoke as a byproduct. There is also a huge lake in the nearby area.

Question. ___________ is the increase in the concentration of harmful chemical substances in the body of living organisms.
(a) Biological oxygen demand
(b) Biomagnification
(c) Biosynthesis
(d) Biogeochemical cycle

Answer : B

Question. An expert agriculturist suggests to the farmer to minimize the use of chemical fertilizers and instead use biofertilizers as they have many advantages over chemical fertilizers.
Which of the following is NOT true for biofertilizers?
(a) They are economical
(b) They help in reducing pollution in the lake
(c) They are renewable
(d) They require large set-up for their production.

Answer : D

Question. A considerable increase in plant life in the lake was noticed after the farming activity intensified.
The most likely reason for this could be:
(a) Chemical fertilizers leached into the lake from the field.
(b) Pesticides leached into the lake from the field.
(c) Organic manure leached into the lake from the field.
(d) Smoke particles from the industry got settled in moist surroundings of the lake.

Answer : A

Question. Consider the following food chain in the same lake.
Aquatic plant → Small fish → Big fish → Birds Which of the above organisms is likely to show minimum amount of pesticide concentration in them after considerable time?
(a) Aquatic plants.
(b) Small fish.
(c) Big fish.
(d) Birds.

Answer : A

Study the passage and answer the questions given below :

The activities of man had adverse effects on all forms of living organisms in the biosphere.
Unlimited exploitation of nature by man disturbed the delicate ecological balance between the living and non-living components of the biosphere. The unfavourable conditions created by man himself threatened the survival not only of him but also of the entire living organisms on the mother earth. One of your classmates is an active member of ‘Eco club’ of your school which is creating environmental awareness amongst the school students, spreading the same in the society and also working hard for preventing environmental degradation of the surroundings.

Question. Which of the following does NOT exist in a balanced ecosystem?
(a) Interconnected food chains.
(b) Interdependence among living organisms and the environment.
(c) Animals dependent on plants but plants are not dependent on animals.
(d) Communities made up of different populations of organisms.

Answer : C

Question. Degradation of non-biodegradable waste is difficult because :
(a) Non-biodegradable wastes cannot be recycled.
(b) Microorganisms cannot decompose it.
(c) They can be made into organic wastes.
(d) All of the above

Answer : B

Question. Which of these group(s) contains only nonbiodegradable items?
(i) Wood, paper, leather
(ii) Polythene, detergent, PVC
(iii) Plastic, detergent, grass
(iv) Plastic, bakelite, DDT
(a) (iii)
(b) (iv)
(c) (i) and (iii)
(d) (ii) and (iv)

Answer : D

Question. The green dustbin signifies:
(a) Non- biodegradable waste
(b) Biodegradable waste
(c) Plastic waste
(d) Garbage

Answer : B

 

Question : In other to maintain proper ecological balance
a) the existing forests should be cleared and new ones should be planted
b) some quick growing annuals should be planted if a tree must be cut for other uses
c) tree must be curt whenever necessary because the underground part performs the useful purpose
d) a tree should be planted in place of one to be cut
Answer :  D
 
Question : Match the following with the correct response: 
Im-4
a) 1-B, 2-D, 3-A, 4-C
b) 1-C, 2-B, 3-D, 4-A
c) 1-D, 2-A, 3-C, 4-B
d) 1-A, 2-C, 3-B, 4-D
Answer :  B
Explanation: Organisms can be grouped as producers, consumers and decomposers according to the manner in which they obtain their sustenance from the environment. Producers or autotrophs prepare their own food. Consumers can be classed as herbivores, carnivores, omnivores and parasites. Herbivores obtain food directly from green plants. Parasites obtain food from a host.
 
Question : A biosphere is composed of
a) living organisms
b) living organisms and lithosphere
c) living organisms, lithosphere and atmosphere
d) living organisms, lithosphere, atmosphere and hydrosphere
Answer :  D
 
Question : Pyramid of energy in a forest ecosystem is
a) always inverted b) always upright
c) both upright and inverted d) first upright then inverted
Answer :  B
 
Question : Secondary treatment in sewage treatment plant involves: 
a) Chemical treatment
b) Physical treatment like sedimentation
c) Passing ultraviolet radiations
d) Biological treatment
Answer :  D

Fill in the blanks.

Question. The top ...... is not killed and eaten by other animals of the ecosystem.
Answer : carnivore

Question. Human beings occupy the ...... position in any food chain.
Answer : top

Question. Human activities have an impact on the ...... .
Answer : environment

Question. Gardens and ...... are artificial ecosystems.
Answer : crop fields

Question. The substances formed in decomposition are released into the ...... and the ...... .
Answer : soil, atmosphere

Question. The flow of energy is ...... .
Answer : unidirectional

 Mark the statements true (T) or false (F).

Question. Forests are artificial ecosystems.
Answer : false

Question. Food chains generally consist of three or four steps.
Answer : true 

Question. All animals which eat plants or other animals are consumers.
Answer :true 

Question. Aquarium cannot be treated as an ecosystem.
Answer : false

Question. Tertiary consumers form the fourth trophic level.
Answer : true 

Write Yes/No.

Question. Does the accumulation of nonbiodegradable pesticides in food chain result in biological magnification?
Answer : Yes

Question. Do gardens represent artificial ecosystem?
Answer : Yes

Question. Is it true that ozone, the deadly poison it is, shields the surface of the earth from UV radiation?
Answer : Yes

Question. The green plants in a terrestrial ecosystem capture about 1% of the energy of sunlight. Is it true?
Answer : Yes

 

Very-Short-Answer Questions

Question. What is the main function of ozone layer of the atmosphere?
Answer : Ozone absorbs ultraviolet rays from sunlight, protecting us from its harmful effects.

Question. Give one example each of herbivore, carnivore and omnivore.
Answer : Rabbits are herbivores, tigers are carnivores and human beings are omnivores

Question. Name the chemical which is mainly responsible for ozone-layer depletion.
Answer : Chlorofluorocarbon

Question. Why do herbivores occupy a position next to producers in a food chain?
Answer : Because herbivores eat only plants,i.e.,producers

Question. Why did United Nations act to control the production of chlorofluorocarbons (CFCs) used in refrigerators?
Answer : CFCs deplete the ozone layer around the earth, hence their production is controlled by United Nations.

Question. The following organisms form a food chain. Which of these will have the highest concentration of non-biodegradable chemicals? Name the phenomenon associated with it. 
Insects, Hawk, Grass, Snake, Frog.
Answer : Hawk will have highest concentration of non-biodegradable chemicals. The phenomenon is called biomagnification.

Question. Define ‘trophic level’.
Answer : Trophic level is the position that an organism occupies in a food chain, where transfer of food or energy takes place.

Question. What is the important function of presence of ozone in earth’s atmosphere?
Answer : The important function of presence of ozone in earth’s atmosphere is that it shields the surface of the earth from ultraviolet (UV) radiations of the sun.

Question. What step is being taken to limit the damage to the ozone layer?
Answer : Judicious use of aerosol spray propellants such as fluorocarbon and chlorofluorocarbons which cause depletion or hole in ozone layer. Control over large scale nuclear explosions and limited use of supersonic planes.

Question. Give an example to illustrate that indiscriminate use of pesticides may result-in the degradation of the environment.
Answer : The pesticides used in crop field are washed down into the water bodies. From water bodies, these are absorbed by aquatic plants and animals of a food chain and thereby degrades the environment.

Question. Name two decomposers operating in our ecosystem.
Answer : Bacteria and fungi.

Question. Why is it necessary to conserve our environment?
Answer : It is necessary to conserve our environment to prevent depletion of natural resources and environmental damage, thereby sustaining life.

Question. What is the role of decomposers in the ecosystem?
Answer : Role of decomposers in the environment:
• They return the nutrients to the nutrient pool.
• They help in completing the different bio-geochemical cycles, thus they maintain the balance in the ecosystem.

Question. Which compounds are responsible for the depletion of ozone layer?
Answer : The compounds responsible for the depletion of ozone layer are chlorofluorocarbons (CFCs).

Question. Why are some substances non- biodegradable?
Answer : Some substances are non-biodegradable because they cannot be broken down into simpler harmless substances in nature.

Question. What is meant by a biodegradable waste?
Answer : Biodegradable wastes are those substances which are broken down into simpler, harmless substances in nature in due course of time by the biological processes such as action of micro organisms like certain bacteria.
Examples: Urine and faecal matter, sewage, agricultural residue, paper, wood, cloth and cattle dung.

Question. What will be the amount of energy available to the organism of the 2nd trophic level of a food chain, if the energy available at the first trophic level is 10,000 joules?
Answer : 100 Joules of energy will be available to the organism of the 2nd trophic level.

Question. What are the various steps in a food chain called?
Answer : The various steps in a food chain are called trophic levels.

Question. Select two non-biodegradable substances from the following waste generated in a kitchen: spoilt food, paper bags, milk bags, vegetable peels, tin cans, used tea leaves.
Answer : Milk bags and tin cans.

Question. Where are CFC found?
Answer : In air-conditioners, refrigerators, aerosol sprays, fire extinguishers

Question. Name any two groups of producers.
Answer : Plants and blue-green algae.

Question. Write the two raw materials for making food, used by living organisms of first tropic level.
Answer : CO2 and Water

Question. Name 4 abiotic components of any ecosystem.
Answer : Temperature, rainfall, wind, soil.

Question. Name the natural cleansing agent in an ecosystem.
Answer : Decomposers, scavengers

Question. Name two natural ecosystem.
Answer : Pond ecosystem and forest ecosystem.

Question. Name any two abiotic components of an environment.
Answer : Water, air.

Question. What is bad Ozone?
Answer : Ozone at ground level is deadly poisonous and is called as bad Ozone.

Question. Name two artificial ecosystem.
Answer : Garden and crop-field.

Question. Name two decomposers.
Answer : Bacteria and fungi

Question. What are consumers in the food chain?
Answer : Those organisms which consume the food produced either directly from producers or indirectly by feeding on other organisms are called consumers.

Question. Which component of sunlight is used for the formation of ozone?
Answer : Ultra violet radiation.

Question. Expand UNEP
Answer : United Nations Environment Programme.

Question. Which disease is caused in human beings due to depletion of ozone layer in the atmosphere?
Answer : Skin cancer, cataract.

Question. Define biological magnification.
Answer : The accumulation of chemicals in the bodies of the organism that belongs to the top most tropic level is called biological magnification.

Question. State different types of consumers in an ecosystem.
Answer : The consumers are herbivores, carnivores, omnivores, parasites, saprophytes and decomposers.

Question. Which compounds are responsible for the depletion of ozone layer?
Answer : Chlorofluorocarbons (CFC)

Question : The importance of ecosystem lies in
a) flow of energy b) cycling of materials c) both of the above d) none of the above
Answer :  C
 
 
 

Short-Answer Questions

Question :  Why are some substances biodegradable and some non-biodegradable? 
Answer :   The substances that are natural or made from natural materials that can be degraded or decomposed by enzymes of decomposer organisms like bacteria & fungi into soil are called Biodegradable substances. e.g.. Fruits & Vegetable peels, Paper etc. These substances do not persist in the environment for long as the enzymes of the decomposer organisms convert them into simple substances & make them available to the plants. The substances that can not be decomposed by decomposer organisms & persist in the environment for long period are called Non Biodegradable substances. e.g.. Plastics, Pesticides etc.
 
Question :  Who gave the ten percent law? 
Answer :  Raymond Lindeman was the scientist who gave the ten percent law of energy.
 
Question :  What are chlorofluorocarbons? 
Answer :  The depletion of the ozone layer is due to the use of the chemicals are called chloroflurocarbon.
 
Question :  What are phytoplanktons? 
Answer : The microscopic aquatic plants freely floating on the surface of the water are called phytoplanktons.
 
Question :  What is garbage? 
Answer :  The household wastes are called garbage.
 
Question :  What is the full form of the CFC?
Answer :  Full form of CFC is Chlorofluorocarbons.  
 
Question : Rearrange the following according to their ascending trophic levels in a food chain. Hawk, grass, snake, frog, grasshopper. 
Answer : Grass →grasshopper →frog →snake →hawk.
A food chain always start with producers and ends with top consumers.
 
Question : Which of the following belong to the first trophic level? 
i. Grasshopper, mango tree, hawk, snake
ii. Sunflower plant, grasshopper, cockroach, banyan tree
Answer : The first trophic level is always the position for Producers thus, in above two cases the first trophic level is captured by,
i. Mango tree
ii. Sunflower plant, banyan tree.
 
Question : What is a ozone and what role does it have in any ecosystem? 
Answer :  Ozone is a form of oxygen. It has the molecular formula O3. It is present at a higher level in the atmosphere. It protects the ecosystem from the harmful effects of ultraviolet rays coming from the Sun. UV rays may cause skin cancer, cataract to us.  Thus ozone forms a protective shield against harmful UV rays.
 

Long Answers

Question : Explain the organisation of an ecosystem. 
Answer :  Organisation of the ecosystem
The structural component of an ecosystem may be classified under two main types:
The biotic components comprise the kinds, number and distribution of living organisms present in an ecosystem. These include plants, animals and microorganisms (bacteria and fungi). Abiotic components consist of the kinds, quantity and distribution of physical and chemical factors such as light, temperature, water, oxygen, carbon, nitrogen and minerals. In this way it is concerned with energy and materials.
The functional aspect of an ecosystem involves the volume and the rate at which the various materials circulate and the rate at which the energy flows through it. The flow of energy is unidirectional. The sun is the ultimate source of energy.
Thus, the study of ecosystem involves the description of biotic communities and the abiotic environment alongwith an understanding of the whole network of relationship involving the exchanges and interactions in these components.
Biotic Components
The biotic components of an ecosystem has been classified by Odum (1971) into three groups:Abiotic components
Though all the abiotic factors are not yet known but many have been understood .
Various important abiotic factors have been classified as follows:
i. Biotic components
ii. Abiotic components
iii. Producers (Green plants)
iv. Macro consumers (Usually animals)
v. Micro consumers (organisms like bacteria and fungi).
vi. Climatic factors. These include light, temperatures, precipitation, atmospheric humidity and wind.
vii. Topographic factors. These include altitude, surface slope and exposure etc.
viii. Edaphic factors. These include soil and substratum.
Chapter 06 Life Processes
CBSE Class 10 Biology Excretion Set A
CBSE Class 10 Biology Excretion Set B
CBSE Class 10 Biology Excretion Set C
CBSE Class 10 Biology Heterotrophic Nutrition Worksheet Set A
CBSE Class 10 Biology Heterotrophic Nutrition Worksheet Set B
CBSE Class 10 Biology Life Processes Nutrition In Animals Worksheet
CBSE Class 10 Biology Life Processes Nutrition In Plants Worksheet
CBSE Class 10 Biology Life Processes Nutrition Worksheet Set A
CBSE Class 10 Biology Life Processes Nutrition Worksheet Set B
CBSE Class 10 Biology Life Processes Nutrition Worksheet Set C
CBSE Class 10 Biology Life Processes Nutrition Worksheet Set D
CBSE Class 10 Biology Life Processes Reference Materials Worksheet
CBSE Class 10 Biology Life Processes Respiration In Animals Worksheet
CBSE Class 10 Biology Life Processes Respiration Worksheet Set A
CBSE Class 10 Biology Life Processes Respiration Worksheet Set B
CBSE Class 10 Biology Life Processes Respiration Worksheet Set C
CBSE Class 10 Biology Life Processes Respiration Worksheet Set D
CBSE Class 10 Biology Life Processes Transporation Worksheet Set A
CBSE Class 10 Biology Life Processes Transporation Worksheet Set B
CBSE Class 10 Biology Life Processes Transporation Worksheet Set C
CBSE Class 10 Biology Life Processes Transporation Worksheet Set D
CBSE Class 10 Biology Life Processes Worksheet
CBSE Class 10 Biology Life Processes Worksheet Set A
CBSE Class 10 Biology Life Processes Worksheet Set B
CBSE Class 10 Biology Life Processes Worksheet Set C
CBSE Class 10 Biology Life Processes Worksheet Set D
CBSE Class 10 Biology Life Processes Worksheet Set E
Chapter 09 Heredity and Evolution
CBSE Class 10 Biology Heredity And Evolution Set D
Chapter 13 Magnetic Effects of Electric Current
CBSE Class 10 Physics Magnetic Effects of Electric Current Worksheet Set E

Chapter 15 Our Environment CBSE Class 10 Science Worksheet

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