NCERT Class 10 Science Chapter 15 Our Environment Question Answer Solution For School Students of Class 10th. We also Provides Notes and Important Questions for Class 10 Science. NCERT Class 10th Science book is applied in mostly boards like CBSE, HBSE, RBSE, Up Board, MP Board and also some other state boards. Class 10 Science Chapter 15 Chapter Inside Questions Solution.
Also Read:- Class 10 Science NCERT Solution
NCERT Class 10 Science Chapter 15 Our Environment Textual Question and Answer for CBSE, HBSE and Other Boards Solution.
Our Environment Class 10 Science Question Answer
Q. 1. Which of the following groups contain only biodegradable items
(a) Grass, flowers and leather
(b) Grass, wood and plastic
(C) Fruit peels, cake and lime juice
(d) Lake, wood and grass.
Ans. (a), (c) and (d)
Q. 2. Which of the following constitute a food chain ?
(a) Grass, wheat and mango
(b) Grass, goat and human
(c) Goat, cow and elephant
(d) Grass, fish and goat.
Ans. (b) Grass, goat and human.
Q. 3. Which of the following are environment friendly practices ?
(a) Carrying cloth bags to put in purchases while shopping
(b) Switching off unnecessary lights and fans
(c) Walking to school instead of getting your mother to drop you in her scooter
(d) All of these.
Ans. (d) All of the above.
Q. 4. What will happen if we kill all the organisms in one trophic level ?
Ans. Ecological imbalance will take place if we kill all the organisms in a trophic level. All food chains of environment are connected to each other. When a level is destroyed completely then living beings of high levels will not be able to get food and energy. If all the lions of a food chain are killed then the population of grass eating deers will increase at uncontrolable rate. Their increased population will eat all grass and turn the region into desert. Sahara desert is an example of this kind of ecological change.
Q. 5. Will the impact of removing all the organisms in a trophic level be different for different trophic levels ? Can the organisms of any trophic level be removed without causing any damage to the ecosystem ?
Ans. Removing all the organisms of a trophic level will affect different trophic levels in different ways.
(1) Effect of removing producers-Eco-system will be completely destroyed if we kill all the producers, there will be no life.
(ii) Effect of removing herbivores-Population of producers (plants and trees) will increase enormously if we kill all the herbivores and carnivores will die because of hunger.
(iii) Effect of removing carnivores-If we kill all the carnivores, then the population of herbivores will increase and it will destroy all the vegetation of a region.
(iv) Effect of removing decomposers-Killing all decomposers will lead to the heaps of dead bodies all around. Various microbes will increase and they will cause different types of diseases. It will lead to deficiency of elements necessary for the growth of plants.
Removal of organisms in a trophic level without affecting the ecosystem is not possible. If we destroy producers, herbivores cannot survive and if we kill herbivores, then carnivores cannot live.
Q. 6. What is biological magnification ? Will the levels of magnification be different at different levels of the ecosystem ?
Ans. Entry of harmful chemicals through various activities in our food chain and their increasing concentration in our body is called as biological magnification. Their entry in our body can be possible through various activities.
We spray insecticides, pesticides and other chemicals to protect crops from diseases. Some amount of that remains in the soil and is used up by the plants through roots mixing with the manure and fertilizers. These chemicals enter our body when we consume product of that crop and their concentration increases when constantly used which results in biological magnification. Man is an omnivore. He eats both plants and animals and has a place in their food chain. That is why chemical substances enter the body easily which leads to biological magnification.
Q. 7. What are the problems caused by non-biodegradable waste that we generate ?
Ans. Non-biodegradable wastes like plastic, DDT, etc, remain in the environment without degradation for unlimited period. Their presence cause problems like
(i) Blockage in severages
(ii) Soil Pollution
(iii) Death of herbivores by swallowing plastic material.
(iv) Biological magnification in humans.
(v) Imbalance in ecosystem
(vi) Water, air and soil pollution
(vii) Problems related to health and beauty.
Q. 8. If all the waste we generate is biodegradable, it will have no effect on our environment ?
Ans. If all the waste generated by us is biodegradable and is decomposed accordingly, then our environment is not adversely affected.
Q. 9. Why is damage to ozone layer a cause of concern ? What steps are being taken to limit this damage ?
Ans. Ozone layer is getting damaged due to various chemical reactions. Due to increase in CFC’s holes are being produced in ozone layer from which UV radiations from sun directly enter the atmosphere of earth and cause diseases like cancer, cataract and skin diseases. Ozone layer absorbs harmful ultravoilet radiations.
To limit this damage United Nation Environment Programme (UNEP) in 1987 laid that the production of CFC’s will be limited as compared to be in 1986. In Montrial protocol (1987) it was suggested to reduce the percentage of CFCs to 50% by 1998. Later it was planned to ban completely CFCs. Now Hydrofluorocarbons is used in place of chlorofluorocarbons in which chlorine and fluorine are missing those used to cause harm to ozone layer. Common people have no awareness for it. It is needed to aware about it. All governments of world should take the following steps:
(1) Minimising the use of Super Sonic Jet Planes
(2) Control on Nuclear explosion
(3) Limiting the use of CFC’s
(4) Research of some alternative of CFCs.