ISC Class 11 Syllabus 2027 Environmental Science

ISC YEAR 2027

INDIAN SCHOOL CERTIFICATE
EXAMINATION

ENVIRONMENTAL
SCIENCE
(877)

February 2025
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MISSION STATEMENT

The Council for the Indian School Certificate
Examinations is committed to serving the nation's
children, through high quality educational
endeavours, empowering them to contribute towards
a humane, just and pluralistic society, promoting
introspective living, by creating exciting learning
opportunities, with a commitment to excellence.

ETHOS OF CISCE

Trust and fair play.
Minimum monitoring.
Allowing schools to evolve their own niche.
Catering to the needs of the children.
Giving freedom to experiment with new ideas
and practices.
Diversity and plurality - the basic strength for
evolution of ideas.
Schools to motivate pupils towards the
cultivation of:
Excellence - The Indian and Global
experience.
Values - Spiritual and cultural - to be the bedrock
of the educational experience.
Schools to have an 'Indian Ethos', strong roots in
the national psyche and be sensitive to national
aspirations.

ENVIRONMENTAL SCIENCE (877)

Aims: 6. To provide a context for the individual student
to reflect on his/her beliefs and values in
1. To help the student appreciate man's place in
relation to the environment.
the natural systems.
7. To provide an opportunity to acquire
2. To provide a wide understanding of knowledge
interdisciplinary skills, knowledge and
resources relevant to environment protection
understanding and to apply this logically and
and conservation.
coherently in the field of environmental
3. To provide an in-depth study of certain conservation.
environment related areas.
8. To encourage student initiative and
4. To place environmental concerns in a resourcefulness in action leading to
technological, social, political and economic environmental protection and conservation.
context.
9. To present environmental concerns in a
5. To provide a context for understanding the role challenging way and thereby encourage
of individual values in conservation. students to consider careers in the
environmental field.

CLASS XI
There will be two papers in the subject: The scale of catchment; quantity of resources
Paper I: Theory - 3 hours ... 70 marks used, land transformation; impact on habitat,
biodiversity, modification of biogeochemical
Paper II: Practical/ Project Work - … 30 marks cycles, modification of climate, substantial
PAPER I - THEORY use to be taught only to create a better
understanding and not for testing
SECTION A
1. Modes of Existence (iv) Their social organisation: size of group;
kinship; division of labour; access to
(i) Modes of existence and resource use: hunting resources.
- gathering; pastoral; agricultural; industrial.
Self-explanatory.
Modes of existence and resource use:
hunting - gathering; pastoral; agricultural; (v) Their ideology and idiom of man-nature
industrial. Two features defining each mode relationship.
of existence.
Self-explanatory.
(ii) Their impact on natural resource base: energy
resources; material resources; scale of (vi) An appreciation of the coexistence of all four
catchment; quantity of resources used. modes of existence in contemporary India.
Impact of each mode on the available natural Self-explanatory.
resources.
(iii) Their ecological impact: land transformation; (vii) Ecological conflicts arising therein.
habitat; diversity; modification of Self -explanatory.
biogeochemical cycles; modification of
climate; substantial use.

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2. Ecology species thrive under different conditions – a
(i) Concept of an ecosystem: definition; basic understanding of the Law of
relationships between living organism, e.g. Tolerance).
competition, predation, pollination, dispersal, Definition of Ecological succession.
food chains, webs; the environment - Classification as primary and secondary.
physical (soil, topography, climate); biotic - Causes (autogenic and allogenic).
types of relationships (competition, Understanding of the stages of succession.
mutualism, parasitism, predation, defence); (v) Biomes: terrestrial; fresh water; marine; a
soil types and vegetation; co-evolution and survey of the biomes of India and their
introduction of species. inhabitants.
Definition of ecology and ecosystem. Examples of Biomes - Tropical rain forests,
Structure of an ecosystem: biotic and abiotic deserts, grasslands, coral reefs, lakes. Any
components. five biomes to be explained with reference to
Trophic relationships: food chains and food climate, topography, flora, fauna and their
webs. Biomagnification and adaptations.
bioaccumulation of toxic wastes.
Relationships between living organisms: 3. Pollution
competition, predation, mutualism, (i) Disruption of nutrient cycles and habitats:
parasitism, commensalism. Examples of each atmospheric pollution; human activities that
type. change the composition of the atmosphere;
Coevolution - Definition and types with connection between pollution and
examples. development; local and global effects
(greenhouse effect, ozone depletion) and
(ii) Habitats and niches: Gause's competitive
their impact on human life; burning of fossil
exclusion principle; resource partitioning.
fuel products - effect on ecosystem and
Definition and a basic understanding of the human health.
above.
• Air pollution: definition and causes.
(iii) Flow of energy: efficiencies - photosynthetic
- trophic - assimilation - production; trophic • Human activities that disrupt
levels; generalised model of the ecosystem; hydrological, carbon, phosphorus and
ecological pyramid (numbers and biomass); nitrogen cycles. The effects of these
food webs. disruptions. An understanding of how
An understanding that a small fraction of the developmental activities lead to air
sun’s energy is captured by the primary pollution. A few examples at local and
producers and thereafter, at every trophic global level.
level, assimilation efficiency reduces. • An understanding of greenhouse effect.
Pyramid of flow of energy. Human sources of greenhouse gases.
(iv) Nutrient cycles: generalised model; a study Explanation of the local and global
of carbon, nitrogen cycles (biological and effects of:
geological); man's intervention; pollution as – burning fossil fuel products (any two)
disruption of these cycles; ecosystem as a
source of material and sink waste for human – global warming with particular
societies; ecological succession - causes reference to the ecosystem, human
(autogenic and allogenic) - patterns of health, sea level, biodiversity and
successions. forests.
An understanding of hydrological, carbon, (ii) Pollution control approaches - prevention and
nitrogen and phosphorous cycles showing the control: as applied to fossil fuel burning; the
linkages between the biotic and abiotic role of PCBs; industrial pollution control -
elements (An understanding that different principles - devices - costs - policy

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incentives; combating global warming; the • Industrial pollution – heat and
international political dimensions; third radioactive substances and their effects –
world interest; impact on economic growth. early hatching of fish eggs, failure to
spawn, decrease in species diversity,
• Need for pollution control. Pollution
migration of aquatic forms.
prevention and control measures – Role of
Pollution Control Boards; one example of • Domestic sewage treatment – primary
a PCB in a metropolitan city. and secondary treatment and treatment
by working with nature.
• Approach: correction at source
(prevention), pollution cleanup – study of • Protective measures taken for conserving
any two common devices. [As applied to marine ecosystems and coastal zone
fossil fuel burning] management.- establishment of
protective marine sanctuaries, integrated
• Industrial pollution: removal of
coastal management, regulated coastal
particulate pollutants (cyclone collector,
development, ban on dumping waste and
electrostatic precipitator) – removal of
sewage in coastal water, ban on dumping
gaseous pollutants by wet dry system.
sludge in oceans, protection of sensitive
• Indoor pollution: Common pollutants, areas from oil drilling, double hull for oil
sources and effect. tankers.
• Subsidies and incentives for green • Soil pollution – sources, effects and
automobiles, green architecture, green mitigation.
energy and green technology in the Indian
context. SECTION B
• Problems related to combating global 4. Legal Regimes for Sustainable Development
warming – lack of international (i) National legislative frameworks for
cooperation, long term issue, effect not environment protection and conservation;
uniform, impact on lifestyle and economy survey of constitutional provisions (including
as a reason for resistance. directive principles); national laws; state laws
• International political dimensions – in India.
developing countries not prepared to take  Constitutional provisions- the Article
steps at the cost of development, demand 48A and 51 A of Directive Principles of
for cheap green technology to reduce State Policy. 73rd and 74th constitutional
emissions. amendment act (Main objectives of the
(iii) Water pollution: water cycle; pollution of above).
surface water, ground water, ocean water;  Legislative framework:
industrial pollution and its effects; domestic
sewage and its treatment - techniques and 1. Environmental Protection Act 1986.
appropriate technology; marine ecosystem The Bhopal Gas Tragedy and how it
protection and coastal zone management; soil influenced Environmental
pollution - sources - effects. Legislation in India – The passing of
• Definition of water pollution. an Umbrella Environmental
Legislation - The Environmental
• Understanding water cycle. Protection Act 1986;
• Causes of pollution of surface, ground 2. Forest (Conservation) Act 1981;
and ocean water and their effects. Point
and non-point sources of water pollution. 3. Wildlife Protection Act 1972;
4. Biological Diversity Act 2002;
• Difficulty in dealing with ground water
pollution.

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5. Water (Prevention and Control of  Industrial revolution - genesis of ongoing
Pollution) Act 1974; technological revolution leading to
development and degradation of
6. Air (Prevention and Control of
environment. Dependence on energy for
Pollution) Act 1981.
all development.
Two main objectives of each of the above
 How technology can be used to generate
Acts to be studied.
a more equitable use of resources and
(ii) International legal regimes: on trade and build environmental sustainability.
environment (GATT, WTO, IPR, TNC's,
(ii) Renewable energy: limitations of
regional arrangements and preferential trade
conventional sources; sources of renewable
arrangements); on climate; on common
energy and their features (solar, wind,
resources (forests, bio-diversities, oceans and
biomass, micro-hydel and muscle power).
space); international institutions (UNEP,
UNCTAD, WHO, UNDP, etc.); international Limitations of conventional sources of energy
initiatives (Earth Summit, Agenda 21). such as - coal, natural gas and oil
(extraction, transportation, storage, pollution
GATT: historical perspective (origin and
and degradation of environment).
objectives and transformation into WTO);
WTO: Principles and functions (Case study Renewable Energy: What is renewable
of disputes, examples); IPR : Types: (a) energy; sources of renewable energy, their
Patents (Products vs Process), (b) features and uses: biomass, solar energy,
Trademark, copyright, geographical wind energy, hydel energy, geothermal
indicators and industrial designs; energy – advantages and disadvantages of
Transnational Corporations (TNC) – renewable energy sources.
definition, impact of TNC on the
(iii) Health: incidents of disease as an indicator of
environment, use of resources, waste
the health of the environment; prevention of
disposal, manmade ecological disaster. Case
diseases by better nutrition, sanitation, access
study of EXXON and BP oil spills
to clean water, etc.; communicable and non-
International institutions (UNEP, UNCTAD, communicable diseases; techniques of low
WHO, UNDP, etc.); international initiatives cost sanitation; policy and organisation to
(Earth Summit, Agenda 21) – a brief provide access to basic health service for all;
understanding of their role in environmental the role of traditional and local systems of
protection. medicine.
 Diseases as indicators of health of the
5. Technology and Environment
Environment: Malaria – standing water,
(i) Technological evolution and models: hi-tech; felling of trees. Enteric diseases –
low-tech; intermediate; appropriate; contaminated water. Respiratory
traditional; interaction between technology, diseases – air pollution.
resources, environment and development;
 How diseases can be prevented by better
energy as a binding factor; the need for
nutrition, sanitation and access to clean
reorienting technology.
water.
 Definition of technology, a brief
 Role of sanitation, water supply, good
overview of the evolution of technology
nutrition in maintenance of health and
and its impact on human societies.
prevention of diseases: Prevention of
 Definitions of hi-tech, low-tech. and deficiency diseases and water borne
intermediate technology – their impacts diseases.
on natural resources.
 Definition of communicable and
 Understanding the difference between non-communicable diseases.
appropriate and traditional technology.

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 Communicable diseases: HIV/AIDS, – Understanding of the term Ecosystem
Tuberculosis, Malaria, Hepatitis as analysis.
examples. Causative agents,
– Composition of the ecosystem – multiple
transmission and prevention of each of
biotic and abiotic factors that influence
the above.
each other. Understanding of limiting
 Non communicable diseases: factors and zone of tolerance. Various
Cardiovascular disease, diabetes, skin factors which are considered as critical
cancer, scurvy and rickets (mal variables.
nutrition), and Chronic Obstructive
– Definition and components of state
Pulmonary Diseases (COPD)- causes
variables.
related to environment and lifestyle.
– Succession: primary and secondary –
 Some techniques of low cost sanitation,
system resilience.
eg. Decomposition system (pit latrine
and ventilated improved pit latrines) and – What are indicator species – examples,
Dry sanitation method. trouts as indicators of water quality,
butterflies as indicators of habitat loss
 Organization of health services in India.
and fragmentation.
Facilities provided by the government for
basic health services in India (to be (ii) Human environment interactions: quantity of
covered briefly). life vs. quality of environment;
environmental issues and problems; role of
 A brief introduction to traditional
belief and values; analysing brief statements
systems of medicine, e.g.: ayurveda,
for underlying values; issues analysis -
unani and local health traditions. Their
separating symptoms from problems;
role in maintaining health of the
problem identification; identifying the
community.
players and their positions; understanding
(iv) Biotechnology: potential; limitations. interacting problems and identifying critical
control points; problems analysis; identifying
 Explanation of the term “Biotechnology’.
variables (human behaviours, values,
 Use/potential of Biotechnology in the ecological, etc.); determining the
field of medicine, industry, relationships between variables; formulating
manufacturing and agriculture. questions for research; planning research;
 Any five limitations of biotechnology generating problems, solution, briefs and
application. specifications.
 Understanding the state of the
 Bioremediation.
environment and the major
SECTION C environmental problems of the 21st
century.
6. Design and Planning for Environmental
Conservation and Protection  The role of belief and values in creating
maintaining and solving environmental
(i) Ecosystem analysis: understanding complex problems.
systems; critical and state variables as system
indicators; indicators of inter-relationships; A case study to be done by the students based
successions and systems resilience; on the following points:
predicting and assessing system responses to  Identification of an environmental issue
impacts and their interventions; rapid in their city/ town/ village.
appraisal methods.
 Identification of the factors/ people
responsible for this issue.

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 Contribution of the local authority / – Proposed construction of a dam
government to curb this problem. (Social impact, Ecological impact).
 Identification to the critical points that – Proposed resort by the sea
have led to the problem. (Ecological impact).
 Urban and rural variations. – Proposed residential complex close
to a forested area / national park in
 Steps to be followed in doing an ‘Action
India (Ecological impact).
Research’ on any environmental
problem. [Interpret the EIA as a good planning and
decision making tool].
(iii) Evaluation and assessment of impacts:
approaches and techniques of environment (iv) Design of solutions: generating solution
and social impact assessment; environment options; overcoming blocks in thinking;
impact assessment as a planning tool and a generative and lateral thinking; using criteria
decision making instrument; interpreting (social, political, ecological, technological,
environment impact assessments. economic) to rank and prioritise solution
ideas; check solutions for economic, social
 Definition and objectives of
and technical viability; collation of solution
‘Environment Impact Assessment’ (EIA).
into coherent plans; planning sequence and
 EIA framework – cost.
– Necessity- screening Self-explanatory.
– Key issues- scoping and focusing To be taught through case studies only.
Students should be encouraged to think
– What to study – assessment
creatively and develop solutions for
– Impact/ identification/evaluation of environmental problems. (For better
significance – evaluation understanding, not for testing).
– Identification of mitigating means –
mitigation
PAPER II-PRACTICAL/PROJECT
WORK
– Report preparation – documentation
Guidelines for Practical/Project Work are given at the
– Reviewing - monitoring end of this syllabus.
 Designing an EIA for the following:

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