Chapter 9

āĻ…āϧ্āϝাāϝ় ⧝

Heredity And Evolution

āĻ—ā§°্āĻ­āϧাā§°āĻŖ āφ⧰ু āĻŦিā§ąā§°্āϤāύ


EXERCISES

āĻŦ্⧟া⧟াāĻŽ āϏāĻŽূāĻš

 1. A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers. but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as

ā§§) āĻŽেāĻŖ্āĻĄেāϞিāϝ়াāύ āĻĒā§°ীāĻ•্āώাāϤ āĻŦেāĻ™ুāύীāϝ়া ā§°āϙ⧰ āĻĢুāϞ āĻĨāĻ•া āĻ“āĻ– āĻŽāϟ⧰ āĻ—āϛ⧰ āϏৈāϤে āĻŦāĻ—া āĻĢুāϞ āĻĨāĻ•া āϚুāϟি āĻŽāϟ⧰ āĻ—āϛ⧰ āĻĒ্ā§°āϜāύāύ āϕ⧰া āĻšৈāĻ›িāϞ। āĻŦংāĻļāϧ⧰ āϏāĻ•āϞোā§ąেāχ āĻŦেāĻ™ুāύীāϝ়া ā§°āϙ⧰ āĻĢুāϞ āϜāύ্āĻŽ āĻĻিāĻ›িāϞ। āĻ•িāύ্āϤু āχāϝ়াā§°ে āĻĒ্ā§°াāϝ় āφāϧা āϚুāϟি āφāĻ›িāϞ। āχāϝ়াā§° āĻĒā§°া āĻ…āύুāĻŽাāύ āϕ⧰িāĻŦ āĻĒাā§°ি āϝে āĻ“āĻ– āĻĒিāϤৃ-āĻŽাāϤৃā§° āϜিāύীāϝ় āĻ—āĻ āύāĻ• āĻāύেāĻĻā§°ে āϚিāϤ্ā§°িāϤ āϕ⧰িāĻŦ āĻĒাā§°ি

 (a) TTWW

 (b) TTww

 (c) TtWW

 (d) TtWw

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2. An example of homologous organs is

⧍) āϏāĻŽā§°ূāĻĒী āĻ…ংāĻ—ā§° āĻāϟা āωāĻĻাāĻšā§°āĻŖ āĻš’āϞ

 (a) our arm and a dog's fore-leg.

(āĻ•) āφāĻŽাā§° āĻŦাāĻšু āφ⧰ু āĻāϟা āĻ•ুāĻ•ুā§°ā§° āφāĻ—āĻ­ā§°ি।

 (b) our teeth and an elephant's tusks.

(āĻ–) āφāĻŽাā§° āĻĻাঁāϤ āφ⧰ু āĻāϟা āĻšাāϤীā§° āĻĻাঁāϤ।

 (c) potato and runners of grass.

(āĻ—) āφāϞু āφ⧰ু āϘাঁāĻšā§° āĻĻৌā§°āĻŦিāĻĻ।

 (d) all of the above.

(āϘ) āĻ“āĻĒā§°ā§° āϏāĻ•āϞোāĻŦোā§°।

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3. In evolutionary terms, we have more in common with

ā§Š/ āĻŦিā§ąā§°্āϤāύ⧰ āĻ•্āώেāϤ্ā§°āϤ āφāĻŽাā§° āϞāĻ—āϤ āĻ…āϧিāĻ• āĻŽিāϞ āφāĻ›ে

 (a) a Chinese school-boy.

(āĻ•) āĻāϜāύ āϚীāύা āϏ্āĻ•ুāϞীāϝ়া āϞ’ā§°া।

 (b) a chimpanzee.

(āĻ–) āĻāϟা āϚিāĻŽ্āĻĒাāĻž্āϜী।

 (c) a spider.

(āĻ—) āĻāϟা āĻŽāϕ⧰া।

 (d) a bacterium.

(āϘ) āĻāϟা āĻŦেāĻ•্āϟেā§°িāϝ়া।

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4. A study found that children with light-coloured eyes are likely to have parents with light-coloured eyes. On this basis, can we say anything about whether the light eye colour trait is dominant or recessive? Why or why not?

4. āĻāϟা āĻ…āϧ্āϝāϝ়āύāϤ āĻĻেāĻ–া āĻ—ৈāĻ›ে āϝে āĻĒাāϤāϞ ā§°āϙ⧰ āϚāĻ•ুāĻĨāĻ•া āĻļিāĻļুā§° āĻĒাāϤāϞ ā§°āϙ⧰ āϚāĻ•ুāĻĨāĻ•া āĻĒিāϤৃ-āĻŽাāϤৃ āĻĨāĻ•াā§° āϏāĻŽ্āĻ­াā§ąāύা āφāĻ›ে। āĻāχ āĻ­িāϤ্āϤিāϤ, āĻĒাāϤāϞ āϚāĻ•ুā§° ā§°āϙ⧰ āĻŦিāĻļেāώāϤ্āĻŦāϟো āĻĒ্ā§°āĻ­াā§ąāĻļাāϞী āύে āĻ…āĻĒ্ā§°āϤ্āϝাāĻļিāϤ āϏেāχ āĻŦিāώāϝ়ে āφāĻŽি āĻ•িāĻŦা āĻ•'āĻŦ āĻĒাā§°োঁāύে? āĻ•িāϝ় āĻŦা āĻ•িāϝ় āύāĻšāϝ়?

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5. How are the areas of study-evolution and classification-interlinked?

ā§Ģ/ āĻ…āϧ্āϝāϝ়āύ-āĻŦিā§ąā§°্āϤāύ āφ⧰ু āĻļ্ā§°েāĻŖীāĻŦিāĻ­াāϜāύ⧰ āĻ•্āώেāϤ্ā§°āϏāĻŽূāĻš āĻ•েāύেāĻ•ৈ āφāύ্āϤঃāϏংāϝোāĻ—ী?

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6. Explain the terms analogous and homologous organs with examples.

ā§Ŧ) āĻ…āύুā§°ূāĻĒ āφ⧰ু āϏāĻŽā§°ূāĻĒী āĻ…ংāĻ— āĻļāĻŦ্āĻĻ āĻĻুāϟা āωāĻĻাāĻšā§°āĻŖ āĻĻি āĻŦ্āϝাāĻ–্āϝা āϕ⧰া।

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7. Outline a project which aims to find the dominant coat colour in dogs. 

ā§­) āĻāϟা āĻĒ্ā§°āĻ•āϞ্āĻĒā§° ā§°ূāĻĒā§°েāĻ–া āĻĻাāĻ™ি āϧ⧰া āϝাā§° āϞāĻ•্āώ্āϝ āĻšৈāĻ›ে āĻ•ুāĻ•ুā§°āϤ āĻĒ্ā§°āϧাāύ āĻ•োāϟ⧰ ā§°ং āĻŦিāϚাā§°ি āωāϞিāĻ“ā§ąা।

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8. Explain the importance of fossils in deciding evolutionary relationships. 

ā§Ž) āĻŦিā§ąā§°্āϤāύāĻļীāϞ āϏāĻŽ্āĻĒā§°্āĻ• āύিā§°্āĻŖāϝ় āϕ⧰াāϤ āϜীā§ąাāĻļ্āĻŽā§° āĻ—ুā§°ুāϤ্āĻŦ āĻŦ্āϝাāĻ–্āϝা āϕ⧰া।

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9. What evidence do we have for the origin of life from inanimate matter?

⧝) āύিā§°্āϜীā§ą āĻĒāĻĻাā§°্āĻĨā§° āĻĒā§°া āϜীā§ąāύ⧰ āĻ‰ā§ŽāĻĒāϤ্āϤিā§° āĻŦিāώāϝ়ে āφāĻŽাā§° āĻšাāϤāϤ āĻ•ি āĻĒ্ā§°āĻŽাāĻŖ āφāĻ›ে?

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10. Explain how sexual reproduction gives rise to more viable variations than asexual reproduction. How does this affect the evolution of those organisms that reproduce sexually?

ā§§ā§Ļ) āϝৌāύ āĻĒ্ā§°āϜāύāύে āĻ…āϝৌāύ āĻĒ্ā§°āϜāύāύāϤāĻ•ৈ āĻ•েāύেāĻ•ৈ āĻ…āϧিāĻ• āĻ•াā§°্āϝ্āϝāĻ•্āώāĻŽ āϤাā§°āϤāĻŽ্āϝ⧰ āϜāύ্āĻŽ āĻĻিāϝ়ে, āϏেāχ āĻŦিāώāϝ়ে āĻŦ্āϝাāĻ–্āϝা āϕ⧰া। āϝৌāύ āĻŦংāĻļāĻŦৃāĻĻ্āϧি āϕ⧰া āϏেāχ āϜীā§ąāĻŦোā§°ā§° āĻŦিā§ąā§°্āϤāύāϤ āχāϝ়াā§° āĻĒ্ā§°āĻ­াā§ą āĻ•েāύেāĻ•ুā§ąা āĻšāϝ়?

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11. How is the equal genetic contribution of male and female parents ensured in the progeny?

ā§§ā§§) āĻŦংāĻļāϧ⧰āϤ āĻĒুā§°ুāώ āφ⧰ু āĻŽāĻšিāϞা āĻĒিāϤৃ-āĻŽাāϤৃā§° āϏāĻŽাāύ āϜিāύীāϝ় āĻ…ā§ąāĻĻাāύ āĻ•েāύেāĻ•ৈ āύিāĻļ্āϚিāϤ āϕ⧰া āĻšāϝ়?

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12. Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement? Why or why not?

⧧⧍) āĻāϟা āϜāύāϏংāĻ–্āϝাāϤ āĻ•েā§ąāϞ āĻāϟা āĻŦ্āϝāĻ•্āϤিāĻ—āϤ āϜীā§ąāĻ• āϏুāĻŦিāϧা āĻĒ্ā§°āĻĻাāύ āϕ⧰া āĻ­িāύ্āύāϤাāĻŦোā§°āĻšে āϜীāϝ়াāχ āĻĨাāĻ•িāĻŦ। āĻāχ āĻŦāĻ•্āϤāĻŦ্āϝāϤ āφāĻĒুāύি āĻāĻ•āĻŽāϤ āύেāĻ•ি? āĻ•িāϝ় āĻŦা āĻ•িāϝ় āύāĻšāϝ়?

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