NCERT Exemplar Class 12 Biology Solutions Chapter 14 Ecosystem

NCERT Exemplar Class 12 Biology Solutions Chapter 14 Ecosystem

Edited By Priyanka kumari | Updated on Aug 26, 2022 03:40 PM IST

NCERT exemplar Class 12 Biology solutions chapter 14 is a wide, yet scoring topic that revolves around different interactions between biotic and abiotic factors of nature known as the ecosystem. NCERT exemplar Class 12 Biology solutions chapter 14 have been prepared by experts and professionals that have studied Biology over years. The experts have made a great attempt at providing students with solutions of NCERT in one of the easiest and convenient methods understandable by students. The solutions given here are well-reviewed and reliable for Board exams and are aligned according to the guidelines provided by CBSE. NCERT exemplar Class 12 Biology solutions chapter 14 pdf download is one of the most convenient ways for 12 Class students to access the study material online as well as offline for best guidance.

Introduction to NCERT Exemplar Class 12 Biology Solutions Chapter 14 Ecosystem

Multiple Choice Questions:

Question:1

Decomposers like fungi and bacteria are:
i. autotrophs
ii. heterotrophs
iii. saprotrophs
iv. chemo-autotrophs.
Choose the correct answer:
(a) i and iii, (b) i and iv (c) ii and iii, (d) i and ii

Answer:

The answer is the option (c) (ii) and (iii)
Explanation: Decomposers depend on other organisms for food. Hence, they are heterotrophs. They obtain nutrients by decomposing the detritus and hence are called saprotrophs.

Question:2

The process of mineralization by microorganisms helps in the release of:
a. inorganic nutrients from humus
b. both organic and inorganic nutrients from detritus
c. organic nutrients from humus
d. inorganic nutrients from detritus and formation of humus.

Answer:

The answer is the option (a) inorganic nutrients from humus
Explanation: The term mineralization means formation of inorganic minerals. Here, microorganisms instead of laboratory methods are carrying out the process.

Question:

Productivity is the rate of production of biomass expressed in terms of:

i. (kcal m–3) yr–1
ii. g–2 yr–1

iii. g–1 yr–1
iv. (kcal m–2) yr–1

(a) ii, (b) iii, (c) ii and iv, (d) i and iii

Answer:

The answer is the option (c) (ii) and (iv)

Question:4

An inverted pyramid of biomass can be found in which the ecosystem?
a. Forest
b. Marine
c. Grassland
d. Tundra

Answer:

The answer is the option (b) Marine
Explanation: In marine environment, the size of fish is much bigger than phytoplankton. Hence, we get an inverted biomass pyramid in marine ecosystem.

Question:5

Which of the following is not a producer?
a. Spirogyra
b. Agaricus
c. Volvox
d. Nostoc

Answer:

The answer is the option (b) Agaricus
Explanation: Agaricus belongs to fungi and hence are saprotrophs, while others belong to algae, which are autrotrophs.

Question:6

Which of the following ecosystems is most productive in terms of net primary production?
a. Deserts
b. Tropical rain forests
c. Oceans
d. Estuaries

Answer:

The answer is the option (b) Tropical rain forests
Explanations: Tropical rain forests have high population density of green plants. Hence, net primary productions are maximum in such conditions.

Question:7

Pyramid of numbers is:
a. Always upright
b. Always inverted
c. Ether upright or inverted
d. Neither upright nor inverted.

Answer:

The answer is the option (c) Ether upright or inverted
Explanation: Number of predators can be more than number of producers, as in case of insects taking food from a tree. This will present an inverted number pyramid. Small number of herbivores feeding on large number of plants will give an upright number pyramid.

Question:8

Approximately how much of the solar energy that falls on the leaves of a plant is converted to chemical energy by photosynthesis?
a. Less than 1%
b. 2-10%
c. 30%
d. 50%

Answer:

The answer is the option (b) 2-10%

Question:9

Among the following, where do you think the process of decomposition would be the fastest?
a. Tropical rain forest
b. Antarctic
c. Dry arid region
d. Alpine region

Answer:

The answer is the option (a) Tropical rain forest
Explanation: There is ambient temperature, good moisture and plenty of sugar in detritus in tropical rain forest. Due to this, rate of decomposition would be fast.

Question:10

How much of the net primary productivity of a terrestrial ecosystem is eaten and digested by herbivores?
a. 1%
b. 10%
c. 40%
d. 90%

Answer:

The answer is the option (b) 10%
Explanation: This obeys the law of 10%

Very Short Answer Type Questions:

Question:1

Name an organism found as a secondary carnivore in an aquatic ecosystem.

Answer:

Shark

Question:3

Under what conditions would a particular stage in the process of succession revert to an earlier stage?

Answer:

Under natural or human-induced disturbances, a particular stage in the process of succession would revert to an earlier stage.

Question:6

Justify the pitcher plant as a producer.

Answer:

Pitcher plant contains chlorophyll and carries out photosynthesis. It feeds on insect only to obtain nitrogen from them. Hence, a pitcher plant is a producer.

Question:7

Name any two organisms which can occupy more than one trophic level in an ecosystem.

Answer:

Sparrow: It is a primary consumer when it feeds on grains but becomes a secondary consumer when it feeds on worms and insects.
Human: On similar lines, the human being is a primary consumer when it feeds on grains and pulses but becomes a secondary consumer when it feeds on a lamb.

Question:8

In the North East region of India, during the process of jhum cultivation, forests are cleared by burning and left for regrowth after a year of cultivation. How would you explain the regrowth of forest in the ecological term?

Answer:

In this case, regrowth of forests is an example of ecological succession. After clearing of forests, the conditions become xerarch which proceeds to mesarch condition after the growth of forests.

Question:9

Climax stage is achieved quickly in secondary succession as compared to primary succession. Why?

Answer:

Soil becomes available after primary succession. It provides an ideal condition for the growth of bigger plants. Secondary succession can be obtained quickly as compared to primary
Succession. Hence, the climax is also reached more quickly.

Question:10

Among bryophytes, lichens and fern which one is a pioneer species in a xeric succession?

Answer:

Lichens are considered as a pioneer species in a xeric succession.

Question:11

What is the ultimate source of energy for the ecosystems?

Answer:

Sun is the ultimate source of energy for the ecosystems.

Question:12

Is the common edible mushroom an autotroph or a heterotroph?

Answer:

The common edible mushroom is a Heterotroph.

Question:13

Why are oceans least productive?

Answer:

Availability of solar radiation is least in oceans, especially in deep oceans. Due to this, oceans are the least productive.

Question:14

Why is the rate of assimilation of energy at the herbivore level called secondary productivity?

Answer:

Secondary productivity is the rate of formation of new organic matter by consumers. The consumers get raw materials for this purpose from producers, which is made possible through assimilation. Due to this, the rate assimilation of energy at the herbivore level is called secondary productivity.

Question:15

Why are nutrient cycles in nature called biogeochemical cycles?

Answer:

Nutrients are cycled through biotic components as well as through abiotic components. The term 'bio' shows biotic components, while 'geo' shows abiotic components. Hence, the nutrient cycles in nature are called biogeochemical cycles.

Question:16

Give any two examples of xerarch succession.

Answer:

Lichen → Bryophytes → Pteridophytes → Gymnosperms and Angiosperms
Lichen → Moss → Ferns → Cycas → Grasses

Question:17

Define self-sustainability.

Answer:

A system that is sustainable without relying on any external input is called a self-sustainable system. This ability of the system is referred to as self-sustainability. Natural ecosystems are self-sustainable.

Question:18

Given below is a figure of an ecosystem. Answer the following questions.

i. What type of ecosystem is shown in the figure?
ii. Name any plant that is characteristic of such an ecosystem.

Answer:

(a) Desert ecosystem
(b) Bushes, acacia, etc.

Question:19

What is common to the earthworm, mushroom, soil mites and dung beetle in an ecosystem?

Answer:

All of them are part of the detritus food chain.

Short Answer Type Questions:

Question:1

Organisms at a higher trophic level have less energy available. Comment.

Answer:

As per the law of 10%, just 10% of the total energy consumed by an organism at a particular trophic level is available for the organism at next trophic level. Therefore, a producer converts whatever energy into biomass; just 10% of it is available for the primary consumer. Similarly, just 10% of the energy consumed by the primary consumer is available for the secondary consumer. Due to this, organisms at a higher trophic level less energy available.

Question:2

The number of trophic levels in an ecosystem is limited Comment

Answer:

In any ecosystem, the number of trophic levels can go up to a maximum of five, and in that case, the food chain will look like the following:
Producer → Primary Consumer → Secondary Consumer → Tertiary consumer → Quaternary Consumer
Let us assume that producer captures 100 units of energy. Out of this, the producer will use 90 units, and 10 units will be available for the primary consumer. Finally, just 0.001 unit will be available for the quaternary consumer, which is a negligible amount of energy.
Hence, more trophic levels are not possible in any ecosystem.

Question:3

Is an aquarium a complete ecosystem?

Answer:

The aquarium is a man-made ecosystem, and it has its own limitations. The confined space of an aquarium cannot have an endless supply of inorganic materials for producers. For supporting even a small number of consumers, there is a need for a large number of producers, which is not possible in a small space provided in an aquarium.
One needs to provide food for the fish in the aquarium, and regular cleaning of the aquarium is also necessary. This shows that an aquarium is not a complete ecosystem because it is not self-sustainable.

Question:4

What could be the reason for the faster rate of decomposition in the tropics?

Answer:

Decomposition is largely an oxygen-requiring process. Moreover, ambient temperature and moisture are also required for this. If detritus is rich in nitrogen and water-soluble substances, then decomposition is faster. All these conditions are available in the tropical climate. Hence, there is a faster rate of decomposition in the tropics.

Question:5

Human activities interfere with the carbon cycle. List any two such activities.

Answer:

Following are the two activities, which interfere with the carbon cycle:
(a) Clearing of forests: Reduced green cover hampers carbonification and thus interferes with the carbon cycle.
(b) Burning of Fossil Fuels: Burning of fossil fuels adds carbon to the atmosphere and increases the percentage of carbon dioxide in the atmosphere. It also interferes with the carbon cycle.

Question:6

The flow of energy through various trophic levels in an ecosystem is unidirectional and non-cyclic. Explain.

Answer:

About 90% of the energy consumed by an organism at a particular trophic level is dissipated in the form of heat energy. This leaves just 10% for the organism at the next trophic level. By the time, it reaches the topmost trophic level; the available energy is an extremely small portion of the energy, which was originally converted by the producer. Due to this, energy flow is unidirectional through various trophic levels and is non-cyclic.

Question:7

Apart from plants and animals, microbes from a permanent biotic component in an ecosystem. While plants have been referred to as autotrophs and animals as heterotrophs, what are microbes referred to as? How do the microbes fulfil their energy requirements?

Answer:

Productivity, decomposition, energy flow and nutrient cycling are integral features of any ecosystem. Plants and animals play important roles in productivity. While some microbes play a role in productivity as some of the microbes are autotrophs, e.g. some algae and some chemosynthetic bacteria. Most of the microbes are heterotrophs. Parasitic microbes get nutrition from the host on which they depend. Many microbes are saprotrophs. They get nutrition from detritus, i.e. they are an important part of the detritus food chain.

Question:8

Poaching of the tiger is a burning issue in today's world. What implication would this activity have on the functioning of the ecosystem of which the tigers are an integral part?

Answer:

Tigers are at the top of the food pyramid in the forest ecosystem and are tertiary consumers. A tertiary consumer helps in checking the uncontrolled population growth of secondary and primary consumers. If all tigers are killed, then no animal will be left to control the population of herbivores. This will result in quick exhaustion of producers. Finally, in the absence of producers, the herbivores will die because of starvation. This will destroy the whole ecosystem.

Question:9

In relation to energy transfer in the ecosystem, explain the statement "10kg of deer's meat is equivalent to 1 kg of lion's flesh".

Answer:

We know that just 10% of the energy consumed at a trophic level is available for the next trophic level. Here 10 kg of deer's meat means 10kg of biomass at the level of primary consumer. Out of this, the deer for its own needs utilizes 90%. Rest 10%, i.e. just 1 kg, is available for the lion. Hence, it is correct to say that 10 kg of deer's meat is equivalent to 1 kg of lion's flesh.

Question:10

Primary productivity varies from ecosystem to ecosystem. Explain?

Answer:

Primary productivity is the biomass produced per unit area over a time period by photosynthesis. In simple terms, we can say that it is the amount of biomass produced by green plants in a particular ecosystem. Plant population varies from one ecosystem to another. The number of plants is higher in tropical rainforests compared to in deserts. Therefore, primary productivity would be much higher in tropical rainforests than in deserts. This shows that primary productivity varies from one ecosystem to another ecosystem.

Question:11

Sometimes, due to biotic/abiotic factor, the climax remains in a particular seral stage (pre-climax) without reaching climax. Do you agree with this statement? If yes, give a suitable example.

Answer:

This entire sequence of communities that successively change in a given area is called sere (s). All the biotic and abiotic factors play a crucial role in this transition process and thus enable a community to reach the climax. If biotic and abiotic factors are not supportive enough for the climax, then the community may remain in a particular seral stage without reaching the climax.
Presence of sparse vegetation at Tabletop Mountain can be one example of a community in the seral stage. The community at the tabletop mountain may be in a stage in which only ferns and mosses may be present. In due course of time, it would pave the way for higher plants.

Question:12

What is an incomplete ecosystem? Explain with the help of a suitable example.

Answer:

An ecosystem, which is devoid of certain biotic or abiotic factors, is called an incomplete ecosystem. An incomplete ecosystem cannot be a self-sustaining ecosystem. The aquarium is a good example of an incomplete ecosystem.
The aquarium may be having producers and consumers, but it does not have decomposers. Lack of decomposers necessitates frequent cleaning of the aquarium.

Question:13

What are the shortcomings of ecological pyramids in the study of the ecosystem?

Answer:

Following are the shortcomings of ecological pyramids:
  1. It does not consider the same species belonging to two or more trophic levels.
  2. It assumes the simple food chain. However, a simple food chain never exists in nature. It is the complex food web which exists in nature.
  3. A food pyramid does not consider the decomposers. But the fact is, decomposers play an important role in the nutrient cycle.

Question:14

How do you distinguish between humification and mineralization?

Answer:

Both humification and mineralization are important aspects of the detritus food chain. Humification leads to the formation of a dark-coloured amorphous substance called humus, while decomposition leads to the formation of inorganic compounds from organic matter.
Mineralization results in a complete breakdown of organic compounds into inorganic compounds, which is not the case with humification.

Question:15

Fill in the trophic levels (1, 2, 3 and 4) in the boxes provided in the figure.

Answer:

1: Producer, 2: Primary Consumer, 3: Secondary Consumer, 4: Tertiary Consumer.

Long Answer Type Questions:

Question:1

A farmer harvests his crop and expresses his harvest in three different ways.
a. I have harvested 10 quintals of wheat.
b. I have harvested 10 quintals of wheat today in one acre of land.
c. I have harvested 10 quintals of wheat in one acre of land, 6 months after sowing.
Do the above statements mean the same thing? If your answer is yes, give reasons. And if your answer is no, explain the meaning of each expression.

Answer:

No, they do not mean the same thing.
  • The first statement implies only the quantity of biomass produced, but it does not comment on the duration and area in which it was produced.
  • The second statement implies the quantity and area, but it does not comment on the duration in which it was produced.
  • The third statement provides the quantity, area, and duration; and this information can be used to calculate primary productivity in the farm: in term of biomass produced.

Question:2

Justify the following statement in terms of ecosystem dynamics. "Nature tends to increase the gross primary productivity, while man tends to increase the net primary productivity".

Answer:

Gross Primary Productivity (GPP) is the rate of production of organic matter in an ecosystem. We get Net Primary Productivity (NPP) on removing respiratory losses (R) from GPP. Nature contributes various factors (biotic and abiotic) to improve the GPP. In other terms, nature tends to increase GPP.
With various agriculture practices, human beings try to increase the NPP. For instance – consider a fruit which is left on the tree for a longer time. Such a fruit will contribute to higher respiratory losses (R). Over the millenniums, human beings have come up with better agricultural practices to reduce the respiratory losses.

Question:3

Which of the following ecosystems will be more productive in terms of primary productivity? Justify your answer. A young forest, a natural old forest, a shallow polluted lake, and alpine meadow.

Answer:

A young forest will have a lower tree density and thus, lower primary productivity. Shallow polluted lake may also have a lower density of flora due to toxicity from pollution. An Alpine meadow is full of grass and thus, a lower tree density.
A natural old forest can be considered a community which has reached climax. It must have a higher tree density and thus a higher level of primary productivity compared to a young forest, a shallow polluted lake, or an alpine meadow.

Question:4

What are the three types of ecological pyramids? What information is conveyed by each pyramid with regard to structure, function, and energy in the ecosystem?

Answer:

Following are the three types of ecological pyramids: -
  1. Pyramid of Numbers: It is arranged from the lower trophic levels at the bottom to higher trophic levels above and shows the number of individuals at each level. Mostly, these pyramids have a wider base (higher producer population).
  2. Pyramid of Biomass: It is arranged from the lower trophic levels at the bottom to higher trophic levels above and shows the biomass (dry weight) at each level. Mostly, these pyramids have a wider base (higher producer population).
  3. Pyramid of Energy: It is arranged from the lower trophic levels at the bottom to higher trophic levels above and shows the energy consumed at each level. These pyramids have a wider base. Unlike the other pyramids, this can never have an inverted shape
In all pyramids, a particular trophic level represents a functional level and an organism may be present at more than a single level. Energy always flows from prey to predator and the availability of energy reduces at subsequent levels.

Question:5

Write a short note on the pyramid of numbers and a pyramid of biomass.

Answer:

Pyramid of Numbers: It is arranged from the lower trophic levels at the bottom to higher trophic levels above and shows the number of individuals at each level. Mostly, these pyramids have a wider base (higher producer population)


Pyramid of Biomass: It is arranged from the lower trophic levels at the bottom to higher trophic levels above and shows the biomass (dry weight) at each level. Mostly, these pyramids have a wider base (higher producer population).

Question:6

Given below is a list of autotrophs and heterotrophs. With your knowledge about the food chain, establish various linkages between the organisms on the principle of 'eating and being eaten'. What is this inter-linkage established known as?
Algae, hydrilla, grasshopper, rat, squirrel, crow, maize plant, deer, rabbit, lizard, wolf, snake, peacock, phytoplankton, crustaceans, whale, tiger, lion, sparrow, duck, crane, cockroach, spider, toad, fish, leopard, elephant, goat, Nymphaea, Spirogyra

Answer:

This linkage that has been established herewith is known as a food web. It pertains to the interlocking between two or more types of the food chain at several tropic levels.
Primary Producer's (Tropic level I): Algae, a maize plant, Phytoplankton, Hydrilla, Nymphaea, and Spirogyra.
Primary Consumer (Tropic level II): Squirrel, grasshopper, deer, rabbit, elephant, crustaceans, mouse, goat.
Secondly Consumer (Tropic level III): Spider, fish, wolf, snake, cockroach, lizard, toad, and crane.
Top carnivore (Tropic level IV): Lion, Tiger. They are topmost carnivores.

Question:7

"The energy flow in the ecosystem follows the second law of thermodynamics." Explain.

Answer:

The entropy of an isolated system never decreases, and such a system will proceed towards thermodynamic equilibrium. A system in thermodynamic equilibrium will have maximum entropy.
An ecosystem requires a constant supply of energy for the synthesis of molecules. Energy always flows unidirectionally in an ecosystem. This is because a reverse flow of energy will make the system unstable (non-equilibrium state). Producers get energy from the sun and become the supplier of energy to the higher trophic levels. Energy always flows from a lower trophic level to a higher one.

Question:8

What will happen to an ecosystem if:
a. All producers are removed.
b. All organisms of herbivore level are eliminated; and
c. All top carnivore population is removed

Answer:

(a) If all producers are removed from the ecosystem, primary consumers will die due to lack of food. In turn, the secondary and tertiary consumers will also become extinct as they will also lose their source of nutrients. Essentially, the ecosystem will end.
(b) If all herbivores (primary consumers) are eliminated from an ecosystem, secondary and tertiary consumers will die due to lack of food. Plants (producers) will see an exponential growth for some time, but as other biotic factors are absent, the biogeochemical cycle will stop. All of this will lead to the end of the ecosystem.
(c) If all carnivores (secondary and tertiary consumers) vanish from the ecosystem, the population of herbivores will see an exponential growth. Their nutrient requirement will lead to overgrazing and the plant(producer) population will die. Eventually, the decreasing population of producers will be unable to support the nutrient requirement of herbivores and they will also die due to starvation.

Question:9

Give two examples of artificial or man-made ecosystems. List the salient features by which they differ from natural ecosystems.

Answer:

Natural Ecosystem
  1. Develops without human intervention.
  2. Many natural ecosystems are spanned over huge areas.
  3. Nutrients are replenished through biogeochemical cycles.
  4. Populations of producers and consumers are in proper balance.
  5. They are self-sustaining
Man-made Ecosystem
  1. Needs human intervention to develop.
  2. Man-made ecosystems span limited area.
  3. Nutrients are replenished by humans, e.g. synthetic fertilizers, feed in aquarium, etc.
  4. Populations of producers and consumers are not in proper balance.
  5. They are not self-sustaining.

Question:10

The biodiversity increases when one moves from the pioneer to the climax stage. What could be the explanation?

Answer:

A rich diversity of flora which can support a larger and diverse consumer set will lead to greater biodiversity of a community.
Lichens, Bryophytes and Pteridophytes are the main plants in the pioneer stage. As these plants do not produce enough food to sustain a diverse fauna, there would be limited biodiversity.
Gymnosperms and Angiosperms become abundant when a community reaches its climax and as they produce enough food to sustain a diverse fauna, biodiversity in such communities will be higher.

Question:11

What will be the P/R ratio of a climax community and a pioneer community? What explanation could you offer for the changes seen in the P/R ratio of a pioneer community and the climax community?

Answer:

P/R ratio of a community is the ratio of gross production and community respiration. This can be one, less than one or more than one.
The ratio can be more or less than one in a pioneer community, but for a climax community it is equal to one. Two situations may be observed In pioneer community -
(a) P/R is more than 1: Level of respiratory loss would be less if there are few consumers, but the gross productivity is high.
(b) P/R is less than 1: Level of respiratory loss be higher than gross productivity if there is a large population of decomposers (or decomposition rate is high) P/R ratio is one for climax community. These communities are stable.

Chapter 14 of Biology deals with the functional unit of nature, called the ecosystem where different organisms interact with the outside environment as well as among themselves. Ecosystems can vary from a small pond to a whole forest. There are a number of different ecosystems existing at a time but they are all connected and linked to one another through direct or indirect relations. The NCERT exemplar Class 12 Biology chapter 14 solutions covers all the important methods, structures and functions happening around us in ecosystems that are linked to one another.
Also, read - NCERT Class 12 Biology Solutions

Class 12 Biology NCERT exemplar solutions chapter 14 studies ecosystem, its input, transfer of energy and output in brief with respect to different terms and concepts introduced in this chapter. The chapter also focuses much on different relationships, cycles, and webs of energy flow existent in the ecosystem simultaneously, and how they all help each other directly or indirectly.

Major Subtopics in NCERT Exemplar class 12 Biology Solutions Chapter 14 Ecosystem:

  • 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

NCERT Exemplar Class 12 Biology Solutions Chapter 14 Ecosystem – Learning Outcomes

Class 12 Biology NCERT exemplar solutions chapter 14 will help students to learn about different methods and processes happening around them in the ecosystem and how are all these connected and linked to one another. The chapter also teaches how the biotic and abiotic components of ecosystem regulate and balance the ecological process through maintenance of nutrient cycle and energy flow among different components of nature.

NCERT exemplar Class 12 Biology solutions are very accurate and are created under expert guidance and review that will help you to prepare for your exams perfectly. They have been thoroughly checked and reviewed by professionals of biology over years that provide a simplified approach to different concepts for better understanding and learning.

NCERT Exemplar Class 12 Biology Chapter Wise Links:

Important Topics in NCERT Exemplar Class 12 Biology Solutions:

All of the important topics of chapter 14, ecosystem have been thoroughly explained and elaborated for simplified learning. Some of the important topics to learn from NCERT exemplar Class 12 Biology solutions are ecosystem, their structure, its functions, and cycles and terms of productivity, decomposition, energy flow, and nutrient cycling.

NCERT exemplar Class 12 Biology solutions chapter 14 also covers the concept of ecological succession that occurs among different communities of ecosystem and how such succession helps or affects different cycles of ecosystem.

The chapter also covers diagrammatic representation of different concepts happening around in the ecosystem and working of cycles, and webs in the ecosystem that will give students an upper hand at scoring and presentation in exams.

NCERT Exemplar Class 12 Solutions Subject Wise:

Check NCERT solutions for questions given in the book:

NEET Highest Scoring Chapters & Topics
Most Scoring concepts For NEET (Based On Previous Year Analysis)
Download EBook

Also, Read NCERT Solution subject wise

Must Read NCERT Notes subject wise

Also Check NCERT Books and NCERT Syllabus here

Frequently Asked Questions (FAQs)

1. What are some of the important topics to cover in NCERT exemplar Class 12 Biology solutions chapter 14?

Some of the most basic and important topics to study from chapter 14, ecosystem are structures and function of ecosystem, the concept of productivity, decomposition, energy flow, relationship between different organisms at varied tropical levels of the food chain, system of ecological succession and different services provided by the ecosystem. 

2. Is the chapter important from the view of Board exams?

Yes, the chapter is important from the view of Board exams and helps students to learn better with the help of proper guidance and solutions provided.

3. What is an ecosystem?

The ecosystem has been defined as the functional unit of nature that is an organization of biotic and abiotic components interacting with one another.

4. Is the material reliable and accessible offline?

Yes, the solutions have been prepared by experts of biology in simple language to aid students, and are accessible offline in the form of pdf download through NCERT exemplar Class 12 Biology solutions chapter 14 pdf download.

Articles

Upcoming School Exams

Application Date:07 October,2024 - 22 November,2024

Application Date:07 October,2024 - 22 November,2024

Application Correction Date:08 October,2024 - 27 November,2024

View All School Exams

Explore Top Universities Across Globe

Get answers from students and experts

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

Back to top