Q.2. what are the major objectives of environmental education?
Ans. Providing awareness, knowledge, a positive attitude about the environment skills and participation toward resolution of environmental problems are the major objectives of environmental education.
Q.3. what is the role of science and engineering in the protection of environment?
Ans. Science and engineering plays a major role in the protection of environment by helping in increasing economic growth and welfare of human society, maintains ecological balance, provides proper knowledge of environment, solves different issues like population measures and food problem and inculcates attitudes and values.
Q.4. List the four conceptual spheres in the earth’s environment.
Ans. Four conceptual spheres in the earth’s environment are
Q.5. Differentiate between Lithosphere and Biosphere.
Ans. The biosphere is composed of all living organisms. Plants, animals, and one-celled organisms while lithosphere contains all of the cold, hard solid land of the planet’s crust (surface), the semisolid land underneath the crust, and the liquid land near the center of the planet.
Q.6. what do you understand by ozone layer?
Ans. Ozone is primarily found in the atmosphere at varying concentrations between the altitudes of 10 to 50 kilometers. This layer of ozone is also called the ozone layer. The ozone layer is important to organisms at the Earth’s surface as it protects them from the harmful effects of the sun’s ultraviolet radiation. Without the ozone layer life could not exist on the Earth’s surface.
Q.7. Ozone is pollutant in troposphere while life server in stratosphere. Justify this statement.
Ans. As ozone is present in troposphere it is a pollutant because in presence of sunlight it breaks into oxygen O2 and nescient oxygen O and react with oxides of nitrogen and hydrocarbon and causes the formation of smog but when that is present in stratosphere it absorbs the ultraviolet radiation of sun and protect the living organisms so known as life saver in stratosphere.
Q.8. Define the term biomes.
Ans. Within the biosphere, living things form ecological communities based on the physical surroundings of an area, these communities are referred to as biomes. Deserts, grasslands, and tropical rainforests are three of the many types of biomes that exist within the biosphere.
Q.9. How an individual can improve the environment?
Ans. An individual can improve the environment by the following ways:
i. By minimising the unnecessarily and exhaustive extraction of the natural resources such as underground water, minerals etc;
ii. By saving the non-renewable energy resources such as burning of fossil fuel;
iii. By increasing the forest cover area; and
iv. By obeying the moral codes meant for achieving a better environment.
Q.10. Define Ecology and Ecosystem.
Ans. The term Ecology was coined by Ernst Haeckel in 1869. It is derived from the Greek words Oikos- home + logos- study. So ecology deals with the study of organism in their natural home interacting with their surroundings. Now ecology is often defined as ‘the study of ecosystem’.
An ecosystem includes a group of biotic communities of species interacting with one another in an area, plus their surroundings, plus all the ways in which they interact with each other and exchanging energy and matter.
Q.11. Differentiate between biome and ecosystem.
Ans. Within the biosphere, living things form ecological communities based on the physical surroundings of an area. These communities are referred to as biomes. A biome is made up of the total of all biological communities interacting with single life zone where the climate is similar.
Deserts, grasslands, and tropical rainforests are three of the many types of biomes that exist within the biosphere whereas an ecosystem includes a group of biotic communities of species interacting with one another in an area, plus their surroundings, plus all the ways in which they interact with each other and exchanging energy and matter.
Q.12. Why are decomposers called ‘micro-consumers’?
Ans. Decomposers like bacteria, actinomycetes and fungi, are heterotrophic organisms feed on organic compounds of dead or living protoplasm of plant and animals for their food and energy. They absorb some of the decomposition products as their food, so as also known as micro- consumers.
Q.13. what role do autotrophs and heterotrophs play in the ecosystem?
Ans. Autotrophs are organisms that can manufacture the organic compounds by converting solar energy into chemical energy with the help of inorganic substances such as water and C02 and organic substances such as enzymes and contribute to build up of organic matter in an ecosystem.
Heterotrophs get their energy and nutrients by feeding directly or indirectly on producers. They cannot make their own food (and need producers). In an ecosystem heterotrophs are called consumers because they depend on others.
Q.14. Distinguish between the following:
Biotic and abiotic components of ecosystem Gross primary productivity and net primary productivity.
Ans. Distinguish between the following:
Biotic components are composed of a variety of living organisms. The plants, animal and micro-organisms present in an ecosystem form the biotic components. These organisms have different nutritional behaviour and status in the ecosystems while abiotic components are nonliving physical and chemical factors of an ecosystem. It includes climatic factors, soil factors, geographical factors, energy, nutrients and toxic substances.
The producers are left with a little less organic matter than what was actually produced by them. This is known as the Net Primary Production (NPP) and the respiratory loss (R) added to it gives the Gross Primary Production (GPP).