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NCERT Solutions for Class 12 Biology Chapter 14 Ecosystem

NCERT Solutions for Class 12 Biology Chapter 14 Ecosystem

Edited By Irshad Anwar | Updated on Sep 18, 2023 07:53 PM IST | #CBSE Class 12th

NCERT Solutions for Class 12 Biology Chapter 14 Ecosystem: Earlier, you learned that a cell is a structural and functional unit of life, so similarly, an ecosystem is a structural and functional unit of nature and comprises both abiotic and biotic components. Solutions to NCERT Class 12 Biology Chapter 14 will make you understand the questions that have been asked from this chapter in the NCERT Textbook and will provide answers for the same. In Ecosystem NCERT Solutions, you will learn that abiotic components are inorganic materials such as air, water, and soil, whereas biotic components are producers, consumers, and decomposers. These NCERT Solutions for Class 12 can be used by students to get ready for their board exams as they are prepared by subject matter experts. Furthermore, these solutions are available for free download in PDF format. Scroll down to go through the questions and answers given in NCERT Solutions for Class 12 Biology Chapter 14.

Ecosystem Class 12 NCERT Solutions explain different types of ecosystems, and each of the ecosystems has a characteristic that results from the interaction between abiotic and biotic components. Also, there are two main structural features of an ecosystem: species composition and stratification. According to Ecosystem NCERT Solutions, based on the source of nutrition, every organism occupies a place in an ecosystem. Class 12 Biology Chapter 14 is curated according to the latest CBSE Syllabus for 2023–24. These Class 12 Biology NCERT Solutions will help students score well in the exams. Ecosystem Class 12 Solutions provide explanations in detail with related and representative examples.

Chapter 14 Biology Class 12 is beneficial to enhance the conceptual knowledge of students. Class 12 Biology Chapter 14 question answer will also help you understand the concepts and topics for the competitive exams as well. If you are looking for the answers to any other class from 6–12, then NCERT Solutions are there for you, as it's the easiest way to get all the Ecosystem NCERT Solutions. As well, Ecosystem Class 12 NCERT PDF can be downloaded.

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NCERT Solutions For Class 12 Biology Ecosystem

According to the latest CBSE Syllabus 2023-24, this chapter has been renumbered as Chapter 12.

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Also Read: NCERT Exemplar for Class 12 Biology Chapter 14 Ecosystem

NCERT Solutions for Class 12 Biology Chapter 14 Ecosystem

Ecosystem NCERT Solutions are given below in the sequence as per NCERT Textbook data:

Class 12 Biology Chapter 14 NCERT Solutions:

Q1. Fill in the blanks.

(a) Plants are called as_________because they fix carbon dioxide.

Answer:

Plants are called as autotrophs because they fix carbon dioxide.

Q1. Fill in the blanks.

(b) In an ecosystem dominated by trees, the pyramid (of numbers) is_________type.

Answer:

In an ecosystem dominated by trees, the pyramid (of numbers) is inverted type.

Q1. Fill in the blanks.

(c) In aquatic ecosystems, the limiting factor for the productivity is_________.

Answer:

In aquatic ecosystems, the limiting factor for productivity is light .

Q1 . Fill in the blanks.

(d) Common detritivores in our ecosystem are_________.

Answer:

Common detritivores in our ecosystem are earthworms

Q1. Fill in the blanks.

(e) The major reservoir of carbon on earth is_________.

Answer:

The major reservoir of carbon on earth is ocean.

Class 12 Biology Chapter 14 NCERT Solutions

Q2 . Which one of the following has the largest population in a food chain?

(a) Producers

(b) Primary consumers

(c) Secondary consumers

(d) Decomposers

Answer:

(d) Decomposers

Decomposers are microorganisms including fungi and bacteria. These break down the remains of dead plants and animals. Decomposers form the largest community of organisms in a food chain.

Ecosystem Class 12 Solutions

Q3. The second trophic level in a lake is

(a) Phytoplankton

(b) Zooplankton

(c) Benthos

(d) Fishes

Answer:

(b) Zooplankton

In a lake, the first trophic level is formed by phytoplankton while the second trophic level is formed by zooplankton.

Ecosystem Class 12 NCERT Solutions

Q4. Secondary producers are:

(a) Herbivores

(b) Producers

(c) Carnivores

(d) None of the above

Answer:

(d) None of the above

In a food chain, plants are the only producers, there are no other producers. Herbivores and carnivores are primary and secondary consumers respectively.

Ecosystem Class 12 Solutions:

Q5. What is the percentage of photosynthetically active radiation (PAR) in the incident solar radiation?

(a) 100%

(b) 50 %

(c) 1-5%

(d) 2-10%

Answer:

(b) 50%

Out of total incident solar radiation, 50 % is formed by photosynthetically active radiation

Ecosystem Class 12 NCERT Solutions:

Q6. Distinguish between

(a) Grazing food chain and detritus food chai

Answer:

Grazing food chain Detritus food chain
Solar energy is utilised Biomass energy stored in bodies of plants and animals is utilised
The grazing food chain starts from producers The detritus food chain starts from detritus i.e. dead plants and animals
It includes a number of trophic levels Detritus food chain includes a lesser number of trophic levels

NCERT Solutions For Class 12 Biology Ecosystem:

Q6. Distinguish between

(b) Production and decomposition

Answer:

Production Decomposition
It is the process of formation of organic matter by producers by means of photosynthesis It is the process of breakdown of complex organic matter into simples organic molecules
It requires sunlight It can take place in the absence of sunlight also


Class 12 Biology Chapter 14 NCERT Solutions

Q6. Distinguish between

(c) Upright and inverted pyramid

Answer:

Upright pyramid Inverted pyramid
Upright pyramids show a decrease in number and biomass from producer level to the tertiary consumer level Inverted pyramids depict an increase in number and biomass from producer level to tertiary consumer level
Pyramid of energy is upright Pyramid of biomass and number can be inverted

Class 12 Biology Chapter 14 Question Answer:

Q6. Distinguish between

(d) Food chain and Food web

Answer:

Food chain Food web
A series of living organisms present at different trophic levels and related to food habits An interconnected web of a number of food chains.
The members at higher trophic level feed upon the members of lower trophic levels. Different organisms have more than one food sources


Class 12 Biology Chapter 14 NCERT Solutions:

Q6. Distinguish between.

(e) Litter and detritus

Answer:

Litter Detritus
The term litter refers to any kind of waste generated The term detritus refers to the dead waste of plants and animals bodies
Litter can be biodegradable as well as non- biodegradable Detritus is biodegradable


Class 12 Ecosystem NCERT Solutions:

Q6. Distinguish between.
(f) Primary and secondary productivity

Answer:

Primary productivity Secondary productivity
Primary productivity refers to the amount of organic matter produced by producers per unit area over a period of time Secondary productivity refers to the rate of production of organic matter by consumers over a period of time

Class 12 Ecosystem NCERT Solutions

Q7. Describe the components of an ecosystem.

Answer:

An ecosystem refers to be the functional unit of nature in which living organisms interact among themselves and also with their surrounding physical environment in order to perform nutrient cycling, energy flow, decomposition and productivity. There are many types of ecosystems such as pond ecosystem, forest ecosystem etc.

Components of ecosystem

The components of the ecosystem can be divided into abiotic components and biotic components

1. Abiotic components- These include the non-living components of nature such as light, temperature, water, soil, air, inorganic nutrients etc.

2. Biotic components- The biotic components of an ecosystem refer to the living organisms present in that ecosystem. The biotic components are divided as producers, consumers and decomposers. Producers are plants, consumers include animals which can be herbivores or carnivores and decomposers include microorganisms like fungi and bacteria.

Ecosystem Class 12 Questions and Answers

Q8. Define ecological pyramids and describe with examples, pyramids of number and biomass.

Answer:

Ecological pyramid- The graphical representation of an ecological parameter such as number, biomass or energy, sequence wise in various trophic levels of a food chain in which producers are at the base, herbivores in the middle and carnivores at the top level. Ecological pyramids can be upright, inverted, or spindle-shaped. The three common types of ecological pyramids include the pyramid of number, pyramid of biomass and pyramid of energy.

1. Pyramids of number- It is the number of individuals per unit area at various trophic levels. It is generally upright, however, the pyramid of number in case of a big tree is generally inverted because number of insects that feed on tree generally exceeds in number.

2. Pyramids of biomass- It represents the biomass in various trophic levels. A pyramid of biomass is upright except in an aquatic food chain. A pyramid of biomass in the sea is generally inverted because the biomass of fishes is generally more than that of phytoplankton.

3. Pyramids of energy- It is the graphic representation of the amount of energy trapped at different trophic levels per unit area. Pyramid of energy is always upright.

Ecosystem Class 12 Questions and Answers:

Q9. What is primary productivity? Give brief description of factors that affect primary productivity.

Answer:

Primary productivity refers to the amount of organic matter or biomass produced by producers per unit area over a period of time. The primary productivity of an ecosystem depends upon a number of factors such as light, temperature, water, precipitation, availability of nutrients etc.

Class 12 Biology Ch 14 Question Answer

Q10. Define decomposition and describe the processes and products of decomposition.

Answer:

Decomposition is the process of breaking down of complex organic matter of detritus into inorganic substances such as carbon dioxide, water and nutrients. Dead remains of plants and animals constitute detritus. The process of decomposition involves steps like fragmentation, leaching, catabolism, humification and mineralization.

1. Fragmentation of Detritus- In this step, the detritus is broken down into small fragments by earthworms

2. Leaching- In leaching the water-soluble nutrients, seep down into the soil and become unavailable salts.

3. Catabolism- The small fragments of decomposed by decomposers like fungi and bacteria with the help of action of enzymes.

4. Humification- In this step, humus is formed. Humus is a dark coloured, amorphous solid substance that acts as a nutrient reserve.

5. Mineralization- In this step by the action of microbes, the inorganic nutrients are released from the humus.

Class 12 Biology Ch 14 Question Answer:

Q11. Give an account of energy flow in an ecosystem

Answer:

Energy Flow in an ecosystem:

All living organisms are dependent for their food on producers, directly or indirectly. There is a unidirectional flow of energy from the sun to producers and then to consumers. Photosynthetically active radiation (PAR) is responsible for the synthesis of food by plants. Animals obtain their food from plants, so they are called consumers. The process of eating and being eaten is called a food chain in which energy flows from producers to consumers. For example, in Grazing food chain, the grass is eaten by goats which are further eaten by man. Similarly, in the detritus food chain, the sequence begins with dead organic matter. It is made up of decomposers which are heterotrophic organisms (fungi and bacteria). These are also known as saprotrophs. Decomposers secrete digestive enzymes that breakdown dead and waste materials into simple, inorganic materials, which are subsequently absorbed by them. Natural interconnection of food chain forms the food web. Thus, in an ecosystem, energy flow occurs through food chains and food webs.

Ecosystem NCERT Solutions

Q12. Write important features of a sedimentary cycle in an ecosystem.

Answer:

The important features of the sedimentary cycle are as follows:

1. These nutrient cycles have their reservoirs in the Earth's crust.

2. Sulphur, calcium, phosphorous etc have sedimentary cycles.

3. Sedimentary cycles are slow, they take more time to complete their circulation and are considered less perfect cycles

Class 12 Biology Chapter 14 Question Answer

Q13. Outline salient features of carbon cycling in an ecosystem.

Answer:

Salient features of carbon cycling are as follows

1. Carbon cycling occurs through atmosphere, ocean and through the living and dead organisms.

2. Most of the carbon is fixed by plants during the process of photosynthesis and returns to the atmosphere in the form of CO2 during respiration.

3. Burning of wood, forest fire and combustion of organic matter, fossil fuel, and volcanic activity are some other sources of releasing CO2 in the atmosphere.

An outline of C-cycle is depicted in the figure given below:

1650516132634

NCERT Solutions for Class 12 Biology Chapter 14 Ecosystem

Ecosystem NCERT Solutions explain about different communities of an ecosystem. The biotic community is dynamic and undergo changes with the passage of time. These changes are sequentially ordered and constitute ecological succession and in the Ecosystem NCERT PDF, you will get all the solutions related to this topic. Succession begins with the invasion of a bare lifeless area by pioneers which later pave way for successors and ultimately a stable climax community is formed, as given in Ch 14 Biology Class 12. The climax community remains stable as long as the environment remains unchanged. We have thorough solutions to every chapter of the NCERT Solutions for Class 12 Biology, which have been updated to the CBSE Syllabus 2023-24.

After going through the ecosystem NCERT, you must be able to answer the questions: common detritivores in our ecosystem are?

Four important components of an ecosystem are:

  1. Productivity
  2. Decomposition
  3. Energy Flow
  4. Nutrient Cycling
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Primary productivity is the rate of capture of solar energy or biomass production of the producers. According to the Biology Chapter 14 Class 12, it is divided into two types:

  • Gross primary productivity (GPP)
  • Net primary productivity (NPP)

NCERT Biology Class 12 defines that nutrient cycling is of two types and these are:

  • Gaseous
  • Sedimentary

you will learn more in Biology Chapter 14 Class 12. If you have any problem in finding the answers to the above questions, then NCERT Solutions for Class 12 Biology Chapter 14: Ecosystem, will help you out.

Try to do all the questions mentioned in CBSE NCERT Solutions for Class 12 Biology Chapter 14 Ecosystem by yourself, because NCERT is the base of your studies and base should always be clear. If you have any doubt or unable to do by yourself then Solutions for NCERT Class 12 Biology Chapter 14 Ecosystem will help you in a very good way, so that you can score good marks not only in 12th Biology board exam as well as also in other competitive exams like NEET.

Important Topics of NCERT Solutions for Class 12 Biology Chapter 14 Ecosystem:

The important topics of Ecosystem Class 12 NCERT Solutions are mentioned below:

Section Name
Topic Name
14
Ecosystem
14.1Ecosystem–Structure and Function
14.2Productivity
14.3Decomposition
14.4Energy Flow
14.5Ecological Pyramids
14.6Ecological Succession
14.7Nutrient Cycling
14.8Ecosystem Services
14.9Summary

Dropped Topics of Ecosystem NCERT Solutions Class 12:

  • 14.6 - Ecological Succession,
  • 14.6.1 - Succession of Plants,
  • 14.7 - Nutrient Cycling,
  • 14.7.1 - Ecosystem – Carbon Cycle,
  • 14.7.2 - Ecosystem – Phosphorus Cycle,
  • 14.8 - Ecosystem Services.

And if you still have any doubts or problems getting the correct answers, then the Ecosystem NCERT PDF will help you. But don't forget to try Ecosystem NCERT Questions at least once so that you can answer those questions by yourself and then check your answers with the help of Ecosystem Class 12 NCERT Solutions.

Highlights of NCERT Solutions Class 12 Biology Chapter 14 – Ecosystem

The key features of CBSE NCERT Solutions for Class 12 Biology Chapter 14 ecosystem are given below:

  • Ecosystem Class 12 NCERT Solutions are written in the best possible way using simple language that makes solutions easier to read and understand
  • In Biology Chapter 14 Class 12 Solutions, points are used to frame answers to help understand quickly.
  • Solutions content for Ecosystem Class 12 NCERT is derived from the textbook by the subject expert.
  • Solutions for Class 12 Biology Chapter 14 are as per the latest CBSE Syllabus and guidelines.
  • Ecosystem Class 12 NCERT PDF links are readily available and easily accessible for free.
  • Important topics are listed in the NCERT solutions for Class 12 biology chapter 14.
  • Ecosystem NCERT will also help you to prepare for your competitive exams like NEET
  • Solutions for Class 12 Biology Chapter 14 Ecosystem NCERT will also help you in your 12th board exam.

NCERT Exemplar Class 12 Solutions

Also Check NCERT Books and NCERT Syllabus here:

NCERT Solutions for Class 12 Biology: Chapter wise

NCERT Solutions for Class 12- Subject wise


We hope you will ace your board examination with the help of NCERT Solutions for Class 12 Biology Chapter 14 Ecosystem.

Frequently Asked Questions (FAQs)

1. What are the four important components of an ecosystem given in ecosystem ncert?
  • Four important components of an ecosystem given in ecosystem ncert are:   
  1.    Productivity   

  2.    Decomposition   

  3.    Energy Flow   

  4.    Nutrient Cycling 

2. What are the important topics of solutions for ecosystem ncert pdf?

The important topics of ecosystem NCERT are:

  • Ecosystem–Structure and Function   
  • Productivity   
  • Decomposition   
  • Energy Flow   
  • Ecological Pyramids   
  • Ecological Succession   
  • Succession of Plants   
  • Nutrient Cycling   
  • Ecosystem – Carbon Cycle   
  • Ecosystem – Phosphorus Cycle   
  • Ecosystem Services  
3. What are the benefits of ecosystem ncert pdf?
  • NCERT is the base of your learning.   
  • You will get all the answers to ecosystem ncert and it will help you to score good marks in the exam.   
  • Ecosystem ncert pdf will also help you with competitive exams like NEET.   
  • NCERT solutions for class 12 biology chapter 14 ecosystem NCERT will also help you in your 12th board exam.  Ecosystem NCERT will also boost your knowledge.  
  • To score well in the examination, follow the NCERT syllabus and solve the exercise given in the NCERT Book. To practice more problems, students must refer to NCERT Exemplar.
4. what are the components of ecosystm given in NCERT Solutions for Class 12 Biology Chapter 14 ?

The components of the ecosystem NCERT can be divided into abiotic components and biotic components:

  1. Abiotic components- These include the non-living components of nature such as light, temperature, water, soil, air, inorganic nutrients etc.  

  2. Biotic components- The biotic components of an ecosystem refer to the living organisms present in that ecosystem. The biotic components are divided as producers, consumers and decomposers. Producers are plants, consumers include animals which can be herbivores or carnivores and decomposers include microorganisms like fungi and bacteria.

5. Can students rely on the careers360 NCERT Solutions for Class 12 Biology Chapter 14?

The NCERT Solutions for Class 12 Biology Chapter 14 are created with the primary goal of assisting students in concentrating on crucial ideas. To improve students' conceptual understanding, every last detail is carefully explained. The solutions also include a number of shortcuts that can be used to effectively remember the concepts. In order to answer the questions from the textbook, students can consult the solutions, and they will have no trouble understanding how to do so.

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Ah, you're looking for CBSE quarterly question papers for mathematics, right? Those can be super helpful for exam prep.

Unfortunately, CBSE doesn't officially release quarterly papers - they mainly put out sample papers and previous years' board exam papers. But don't worry, there are still some good options to help you practice!

Have you checked out the CBSE sample papers on their official website? Those are usually pretty close to the actual exam format. You could also look into previous years' board exam papers - they're great for getting a feel for the types of questions that might come up.

If you're after more practice material, some textbook publishers release their own mock papers which can be useful too.

Let me know if you need any other tips for your math prep. Good luck with your studies!

It's understandable to feel disheartened after facing a compartment exam, especially when you've invested significant effort. However, it's important to remember that setbacks are a part of life, and they can be opportunities for growth.

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  4. Focus on NEET 2025 Preparation:

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  5. Seek Support:

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Remember: This is a temporary setback. With the right approach and perseverance, you can overcome this challenge and achieve your goals.

I hope this information helps you.







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hello mahima,

If you have uploaded screenshot of your 12th board result taken from CBSE official website,there won,t be a problem with that.If the screenshot that you have uploaded is clear and legible. It should display your name, roll number, marks obtained, and any other relevant details in a readable forma.ALSO, the screenshot clearly show it is from the official CBSE results portal.

hope this helps.

Hello Akash,

If you are looking for important questions of class 12th then I would like to suggest you to go with previous year questions of that particular board. You can go with last 5-10 years of PYQs so and after going through all the questions you will have a clear idea about the type and level of questions that are being asked and it will help you to boost your class 12th board preparation.

You can get the Previous Year Questions (PYQs) on the official website of the respective board.

I hope this answer helps you. If you have more queries then feel free to share your questions with us we will be happy to assist you.

Thank you and wishing you all the best for your bright future.

A block of mass 0.50 kg is moving with a speed of 2.00 ms-1 on a smooth surface. It strikes another mass of 1.00 kg and then they move together as a single body. The energy loss during the collision is

Option 1)

0.34\; J

Option 2)

0.16\; J

Option 3)

1.00\; J

Option 4)

0.67\; J

A person trying to lose weight by burning fat lifts a mass of 10 kg upto a height of 1 m 1000 times.  Assume that the potential energy lost each time he lowers the mass is dissipated.  How much fat will he use up considering the work done only when the weight is lifted up ?  Fat supplies 3.8×107 J of energy per kg which is converted to mechanical energy with a 20% efficiency rate.  Take g = 9.8 ms−2 :

Option 1)

2.45×10−3 kg

Option 2)

 6.45×10−3 kg

Option 3)

 9.89×10−3 kg

Option 4)

12.89×10−3 kg

 

An athlete in the olympic games covers a distance of 100 m in 10 s. His kinetic energy can be estimated to be in the range

Option 1)

2,000 \; J - 5,000\; J

Option 2)

200 \, \, J - 500 \, \, J

Option 3)

2\times 10^{5}J-3\times 10^{5}J

Option 4)

20,000 \, \, J - 50,000 \, \, J

A particle is projected at 600   to the horizontal with a kinetic energy K. The kinetic energy at the highest point

Option 1)

K/2\,

Option 2)

\; K\;

Option 3)

zero\;

Option 4)

K/4

In the reaction,

2Al_{(s)}+6HCL_{(aq)}\rightarrow 2Al^{3+}\, _{(aq)}+6Cl^{-}\, _{(aq)}+3H_{2(g)}

Option 1)

11.2\, L\, H_{2(g)}  at STP  is produced for every mole HCL_{(aq)}  consumed

Option 2)

6L\, HCl_{(aq)}  is consumed for ever 3L\, H_{2(g)}      produced

Option 3)

33.6 L\, H_{2(g)} is produced regardless of temperature and pressure for every mole Al that reacts

Option 4)

67.2\, L\, H_{2(g)} at STP is produced for every mole Al that reacts .

How many moles of magnesium phosphate, Mg_{3}(PO_{4})_{2} will contain 0.25 mole of oxygen atoms?

Option 1)

0.02

Option 2)

3.125 × 10-2

Option 3)

1.25 × 10-2

Option 4)

2.5 × 10-2

If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will

Option 1)

decrease twice

Option 2)

increase two fold

Option 3)

remain unchanged

Option 4)

be a function of the molecular mass of the substance.

With increase of temperature, which of these changes?

Option 1)

Molality

Option 2)

Weight fraction of solute

Option 3)

Fraction of solute present in water

Option 4)

Mole fraction.

Number of atoms in 558.5 gram Fe (at. wt.of Fe = 55.85 g mol-1) is

Option 1)

twice that in 60 g carbon

Option 2)

6.023 × 1022

Option 3)

half that in 8 g He

Option 4)

558.5 × 6.023 × 1023

A pulley of radius 2 m is rotated about its axis by a force F = (20t - 5t2) newton (where t is measured in seconds) applied tangentially. If the moment of inertia of the pulley about its axis of rotation is 10 kg m2 , the number of rotations made by the pulley before its direction of motion if reversed, is

Option 1)

less than 3

Option 2)

more than 3 but less than 6

Option 3)

more than 6 but less than 9

Option 4)

more than 9

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