Short Answer Questions
Q1. What do you understand by Environment?
Ans: The immediate natural surroundings of man is called environment. E.g.: Plants, Air, Water, Landforms, Wildlife, etc.......
The word Environment has been derived from a French word "Environner" which means "Neighborhood".
Q2. Write a short note on Biosphere.
Ans: Plant and animal kingdom together make biosphere or the living world. It is a narrow zone of the earth where Land (Lithosphere), Water (Hydrosphere) and Air (Atmosphere) interact with each other to support life. Biosphere makes the earth a unique planet in the solar system.
Q3. Describe ecosystem.
Ans: The Interrelation between plants and animals in the natural environment is called Ecosystem. There could be an ecosystem of large rain forest, grassland, desert, mountains, lake, river, ocean and even a small pond.
Q4. Explain the composition of the air.
Ans: Atmosphere is composed of various gases. Major gases present are: Nitrogen – 78%, Oxygen – 21%, Argon - .93%, Carbon Dioxide – 0.03%, Other Gases – 0.04% (like – helium, hydrogen, methane, ozone, etc. and water vapours & dust particles.
Long Answer Questions
Q5. What are the major components of environment?
Ans: Different components of the environment are:
(a) Natural Environment (b) Human Environment (c) Human Made Environment
Q6. Discuss lithosphere as one of the domains of the earth.
Ans: The hard outermost solid layer of the earth which is made up of rock material is called crust. This solid crust of the earth is called Lithosphere. On this lithosphere we find different landforms such as the mountains, plateaus and plains. It provides us land where we live and also, it is a great source of vegetation, wildlife and mineral wealth. The crust is covered by a thin layer of soil which is of great importance for life. Lithosphere provides us the three basic necessities of life, i.e. Food, Cloth and Shelter.
Q7. How do plants and animals depend on each other?
Ans: All plants, animals and human beings depend on their immediate surroundings. Often they are also interdependent on each other. "This relation between the living organisms, as well as the relation between the organisms and their surroundings form an ecosystem". There could be an ecosystem of large rain forest, grassland, desert, mountains, lake, river, ocean and even a small pond. In every ecosystem, there is a perfect balance in the transfer of energy and matter among the different components. This is known as Ecological Balance.
To maintain the balance "Food Chain" is the best example, in the process plants produce food for themselves and the plants are consumed by herbivores and herbivores by carnivores, (Omnivores eat both plants and animals) and ultimately, when these plants and animals die they are decomposed by the decomposers and thus, the dead matter of plants and animals is converted into simple compound which then enter the soil and air.
Q8. Discuss the interdependence of human world and environment.
Ans: Human world entirely depends on the environment for their survival. The basic needs of life (i.e. food, cloth and shelter) are fulfilled by the environment. But in the current scenario few of the human activities have caused great imbalance in the environment, for e.g. Deforestation, Overgrazing, Pollution, Casual & careless attitude towards the environment, Urbanization, Industrialization, Overpopulation, etc.
Now, a perfect balance is required between the natural and human environment. Survival of human being is not possible without the natural environment. Thus, we should always try and protect our environment and human beings live a long and healthy life.
HOTS (High Order Thinking) Questions
Q9. Why would the earth be barren without the atmosphere?
Ans: The layer of air around us is called Atmosphere. Following is the importance of atmosphere: -
(a) It gives us life giving gases like oxygen for breathing of animal kingdom and carbon dioxide is inhaled by plant kingdom.
(b) It has Ozone layer which protects us from the harmful ultraviolet rays of the sun.
(c) There are tiny dust particles in the atmosphere which helps in the formation of the rain droplets.
(d) It acts as a blanket which prevents the earth from becoming too hot during day and too cold during night.
(e) It protects us from falling meteors and other cosmic dusts. They burn when coming in contact with the atmosphere.
(f) Presence of gases, dust particles and water vapours lend colours to the sky.
Thus, atmosphere plays a very vital role and in its absence there won't be any life and earth will be barren.
Q10. Why are human beings the most important part of the human environment?
Ans. There are a number of different things that make humans different from other creatures. Human beings adapt themselves to the natural environment by making modifications in their food, cloth and shelter. They also modify their natural environment to suit their social, biological, cultural and economic needs.
The early human beings slept on trees and caves, they used to roam around in search of food as that of other creatures but with the passage of time, with the help of their mind, thinking skills, ability, knowledge, hard work, etc. they have changed themselves drastically. Now, the modern man is far more organized, skilled, well mannered and cultured. They live in houses, eat cooked food, travel from one place to another by various means of transportation, etc.