Chapter - 15 

Our Environment

( āφāĻŽাā§° āĻĒā§°িā§ąেāĻļ )


EXERCISES:-

( āĻŦ্āϝাāϝ়াāĻŽ:- )

1. Which of the following groups contain only biodegradable items?

( āύিāĻŽ্āύāϞিāĻ–িāϤ āĻ•োāύāϟো āĻ—োāϟāϤ āĻ•েā§ąāϞ āϜৈā§ą-āĻĒāϚāύāĻļীāϞ āϏাāĻŽāĻ—্ā§°ী āĻĨাāĻ•ে? )

(a) Grass, flowers and leather 

( āϘাঁāĻš, āĻĢুāϞ āφ⧰ু āϚাāĻŽā§°া )

(b) Grass, wood and plastic

( āϘাঁāĻš, āĻ•াāĻ  āφ⧰ু āĻĒ্āϞাāώ্āϟিāĻ• )

(c) Fruit-peels, cake and lime-juice

( āĻĢāϞ⧰ āĻŦাāĻ•āϞি, āĻ•েāĻ• āφ⧰ু āϚূāĻŖā§° ā§°āϏ )

(d) Cake, wood and grass

( āĻ•েāĻ•, āĻ•াāĻ  āφ⧰ু āϘাঁāĻš )

Answer:-

2. Which of the following constitute a food-chain?

( āύিāĻŽ্āύāϞিāĻ–িāϤ āĻ•োāύāϟোā§ąে āĻ–াāĻĻ্āϝ-āĻļৃংāĻ–āϞা āĻ—āĻ āύ āϕ⧰ে? )

(a) Grass, wheat and mango

( āϘাঁāĻš, āϘেঁāĻšু āφ⧰ু āφāĻŽ )

(b) Grass, goat and human

( āϘাঁāĻš, āĻ›াāĻ—āϞী āφ⧰ু āĻŽাāύুāĻš )

(c) Goat, cow and elephant

( āĻ›াāĻ—āϞী, āĻ—ā§°ু āφ⧰ু āĻšাāϤ )

(d) Grass, fish and goat

( āϘাঁāĻš, āĻŽাāĻ› āφ⧰ু āĻ›াāĻ—āϞী )

Answer:-

3. Which of the following are environment-friendly practices?

( āύিāĻŽ্āύāϞিāĻ–িāϤ āĻ•োāύāϟো āĻĒā§°িā§ąেāĻļ-āĻ…āύুāĻ•ূāϞ āĻ…āĻ­্āϝাāϏ? )

(a) Carrying cloth-bags to put purchases in while shopping

( āĻŦāϜাā§° āϕ⧰োঁāϤে āĻ•্ā§°āϝ় āϕ⧰িāĻŦāϞৈ āĻ•াāĻĒোā§°ā§° āĻŽোāύা āĻ•āĻĸ়িāϝ়াāχ āύিāϝ়া )

(b) Switching off unnecessary lights and fans

( āĻ…āĻĒ্ā§°āϝ়োāϜāύীāϝ় āϞাāχāϟ āφ⧰ু āĻĢেāύ āĻŦāύ্āϧ āϕ⧰া )

(c) Walking to school instead of getting your mother to drop you on her scooter

( āφāĻĒোāύাā§° āĻŽাāĻ•āĻ• āϤাāχ⧰ āϏ্āĻ•ুāϟাā§°āϤ āĻĒেāϞাāχ āĻĻিāϝ়াā§° āϏāϞāύি āϏ্āĻ•ুāϞāϞৈ āĻ–োāϜ āĻ•āĻĸ়া )

(d) All of the above

( āĻ“āĻĒā§°োāĻ•্āϤ āϏāĻ•āϞোāĻŦোā§° )

Answer:-

4. What will happen if we kill all the organisms in one trophic level?

( āϝāĻĻি āφāĻŽি āϏāĻ•āϞো āϜীā§ąāĻ• āĻāϟা āϟ্ā§°āĻĢিāĻ• āϏ্āϤ⧰āϤ āĻšāϤ্āϝা āϕ⧰োঁ āϤেāύ্āϤে āĻ•ি āĻš'āĻŦ? )

Answer:-

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?

( āĻŦিāĻ­িāύ্āύ āϟ্ā§°āĻĢিāĻ• āϏ্āϤ⧰⧰ āĻŦাāĻŦে āϏāĻ•āϞো āϜীā§ąāĻ• āϟ্ā§°āĻĢিāĻ• āϏ্āϤ⧰āϤ āφঁāϤ⧰ āϕ⧰াā§° āĻĒ্ā§°āĻ­াā§ą āĻĒৃāĻĨāĻ• āĻš'āĻŦāύে? āĻ•োāύো āϟ্ā§°āĻĢিāĻ• āϏ্āϤ⧰⧰ āϜীā§ąāĻŦোā§° āĻĒā§°িā§ąেāĻļ āϤāύ্āϤ্ā§°ā§° āĻ•োāύো āĻ•্āώāϤি āύāϕ⧰াāĻ•ৈ āφঁāϤ⧰ āϕ⧰িāĻŦ āĻĒাā§°িāύে? )

Answer:-

6. What is biological magnification? Will the levels of this magnification be different at different levels of the ecosystem?

( āϜৈā§ąিāĻ• āĻŦিāĻŦā§°্āϧāύ āĻ•ি? āĻĒā§°িā§ąেāĻļ āϤāύ্āϤ্ā§°ā§° āĻŦিāĻ­িāύ্āύ āϏ্āϤ⧰āϤ āĻāχ āĻŦিāĻŦā§°্āϧāύ⧰ āϏ্āϤ⧰ āĻĒৃāĻĨāĻ• āĻš'āĻŦāύে? )

Answer:-

7. What are the problems caused by the non-biodegradable wastes that we generate?

( āφāĻŽি āϏৃāώ্āϟি āϕ⧰া āĻ…-āϜৈā§ą-āĻĒāϚāύāĻļীāϞ āĻ†ā§ąā§°্āϜāύাā§° āĻĢāϞāϤ āĻ•ি āĻ•ি āϏāĻŽāϏ্āϝা āĻšāϝ়? )

Answer:-

8. If all the waste we generate is biodegradable, will this have no impact on the environment?

( āϝāĻĻি āφāĻŽি āĻ‰ā§ŽāĻĒāύ্āύ āϕ⧰া āϏāĻ•āϞো āĻ†ā§ąā§°্āϜāύা āϜৈā§ą-āĻĒāϚāύāĻļীāϞ āĻšāϝ়, āχāϝ়াā§° āĻĒā§°িā§ąেāĻļā§° āĻ“āĻĒā§°āϤ āĻ•োāύো āĻĒ্ā§°āĻ­াā§ą āύāĻĒā§°ে āύেāĻ•ি? )

Answer:-

9. Why is damage to the ozone layer a cause for concern? What steps are being taken to limit this damage?

( āĻ“āϜোāύ āϏ্āϤ⧰⧰ āĻ•্āώāϤি āĻ•িāϝ় āϚিāύ্āϤাā§° āĻ•াā§°āĻŖ? āĻāχ āĻ•্āώāϤি āϏীāĻŽিāϤ āϕ⧰িāĻŦāϞৈ āĻ•ি āĻĒāĻĻāĻ•্āώেāĻĒ āϞোā§ąা āĻšৈāĻ›ে? )

Answer:-





Post ID : DABP004565