Chapter 15
āĻ āϧ্āϝাāϝ় ā§§ā§Ģ
Our Environment
āĻāĻŽাā§° āĻĒā§°িā§ąেāĻļ
EXERCISES
āĻŦ্āϝাāϝ়াāĻŽ
ā§§/ āϤāϞ⧰ āĻোāύāĻো āĻোāĻāϤ āĻেā§ąāϞ āĻৈā§ą-āĻŦিāĻ্āύিāϤ āϏাāĻŽāĻ্ā§°ীāĻšে āĻĨাāĻে?
(āĻ) āĻাঁāĻš, āĻĢুāϞ āĻā§°ু āĻাāĻŽā§°া
(āĻ) āĻাঁāĻš, āĻাāĻ āĻā§°ু āĻĒ্āϞাāώ্āĻিāĻ
(āĻ) āĻĢāϞ⧰ āĻোāϞা, āĻেāĻ āĻā§°ু āĻূāĻŖā§° ā§°āϏ
(āĻ) āĻĒিāĻ া, āĻাāĻ āĻā§°ু āĻাঁāĻš
2. Which of the following constitute a food-chain?
⧍/ āϤāϞ⧰ āĻোāύāĻোā§ąে āĻাāĻĻ্āϝ-āĻļৃংāĻāϞ āĻāĻ āύ āĻā§°ে?
(āĻ) āĻাঁāĻš, āĻেঁāĻšু āĻā§°ু āĻāĻŽ
(āĻ) āĻাঁāĻš, āĻাāĻāϞী āĻā§°ু āĻŽাāύুāĻš
(āĻ) āĻাāĻāϞী, āĻā§°ু āĻā§°ু āĻšাāϤী
(āĻ) āĻাঁāĻš, āĻŽাāĻ āĻā§°ু āĻাāĻāϞী
3. Which of the following are environment-friendly practices?
ā§Š/ āϤāϞ⧰ āĻোāύāĻŦোā§° āĻĒā§°িā§ąেāĻļ-āĻŦāύ্āϧুāϤ্āĻŦāĻĒূā§°্āĻŖ āĻĒāĻĻ্āϧāϤি?
(a) Carrying cloth-bags to put purchases in while shopping
(āĻ) āĻŦāĻাā§° āĻā§°াā§° āϏāĻŽāϝ়āϤ āĻ্ā§°āϝ় āĻā§°া āĻŦāϏ্āϤু āĻĨ’āĻŦāϞৈ āĻাāĻĒোā§°-āĻŦেāĻ āĻāĻĸ়িāϝ়াāĻ āύিāϝ়া
(b) Switching off unnecessary lights and fans
(āĻ) āĻ āĻĒ্ā§°āϝ়োāĻāύীāϝ় āϞাāĻāĻ āĻā§°ু āĻĢেāύ āĻŦāύ্āϧ āĻā§°া
(āĻ) āĻŽাāĻে āϤোāĻŽাāĻ āϏ্āĻুāĻীāϤ āύāĻŽাāĻ āĻĻিāϝ়াā§° āĻĒā§°িā§ąā§°্āϤে āĻোāĻāĻাāĻĸ়ি āϏ্āĻুāϞāϞৈ āϝোā§ąা
(āĻ) āĻāĻĒā§°ā§° āϏāĻāϞোāĻŦোā§°
4. What will happen if we kill all the organisms in one trophic level?
ā§Ē/ āĻāĻŽি āϝāĻĻি āϏāĻāϞো āĻীā§ąāĻ āĻāĻা āĻ্ā§°āĻĢিāĻ āϞেāĻেāϞāϤ āĻŽাā§°ি āĻĒেāϞাāĻঁ āϤেāύ্āϤে āĻি āĻš’āĻŦ?
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?
ā§Ģ/ āĻāĻা āĻ্ā§°āĻĢিāĻ āϏ্āϤ⧰āϤ āĻĨāĻা āϏāĻāϞো āĻীā§ą āĻঁāϤ⧰োā§ąাā§° āĻĒ্ā§°āĻাā§ą āĻŦিāĻিāύ্āύ āĻ্ā§°āĻĢিāĻ āϏ্āϤ⧰⧰ āĻŦাāĻŦে āĻŦেāϞেāĻ āĻš’āĻŦāύে? āĻĒā§°িā§ąেāĻļ āϤāύ্āϤ্ā§°ā§° āĻোāύো āϧ⧰āĻŖā§° āĻ্āώāϤি āύāĻā§°াāĻৈ āϝিāĻোāύো āĻ্ā§°āĻĢিāĻ āϏ্āϤ⧰⧰ āĻীā§ąāĻŦোā§° āĻঁāϤ⧰াāĻ āĻĒেāϞাāĻŦ āĻĒাā§°িāύে?
6. What is biological magnification? Will the levels of this magnification be different at different levels of the ecosystem?
ā§Ŧ/ āĻৈā§ąিāĻ āĻŦৃāĻĻ্āϧি āĻি? āĻĒā§°িā§ąেāĻļ āϤāύ্āϤ্ā§°ā§° āĻŦিāĻিāύ্āύ āϏ্āϤ⧰āϤ āĻāĻ āĻŦৃāĻĻ্āϧিā§° āĻŽাāϤ্ā§°া āĻŦেāϞেāĻ āĻŦেāϞেāĻ āĻš’āĻŦāύে?
7. What are the problems caused by the non-biodegradable wastes that we generate?
ā§/ āĻāĻŽি āĻā§āĻĒāύ্āύ āĻā§°া āĻ āĻৈā§ą-āĻŦিāĻ্āύিāϤ āĻā§ąā§°্āĻāύাāĻŦোā§°ā§° āĻĢāϞāϤ āĻি āĻি āϏāĻŽāϏ্āϝাā§° āϏৃāώ্āĻি āĻšāϝ়?
8. If all the waste we generate is biodegradable, will this have no impact on the environment?
ā§Ž/ āĻāĻŽি āĻā§āĻĒāύ্āύ āĻā§°া āϏāĻāϞো āĻā§ąā§°্āĻāύা āϝāĻĻি āĻৈā§ą-āĻŦিāĻ্āύিāϤ āĻšāϝ় āϤেāύ্āϤে āĻāϝ়াā§° āĻĒā§°িā§ąেāĻļāϤ āĻোāύো āĻĒ্ā§°āĻাā§ą āύāĻĒā§°েāύে?
9. Why is damage to the ozone layer a cause for concern? What steps are being taken to limit this damage?
⧝/ āĻ ’āĻāύ āϏ্āϤ⧰⧰ āĻ্āώāϤি āĻিāϝ় āĻিāύ্āϤাā§° āĻাā§°āĻŖ? āĻāĻ āĻ্āώāϤি āϏীāĻŽিāϤ āĻā§°িāĻŦāϞৈ āĻি āĻĒāĻĻāĻ্āώেāĻĒ āĻ্ā§°āĻšāĻŖ āĻā§°া āĻšৈāĻে?