Đột biến nhiễm sắc thể

Home Lớp 9 Khoa học tự nhiên 9 - sách kết nối tri thức Bài 46: Đột biến nhiễm sắc thểBài tập cơ bản

{"common":{"save":0,"post_id":"8711","level":1,"total":10,"point":10,"point_extra":0},"segment":[{"id":"10667","post_id":"8711","mon_id":"1159533","chapter_id":"1159701","question":"\u1ede \u0111\u1eadu Hà Lan có 2n = 14. Th\u1ec3 d\u1ecb b\u1ed9i t\u1ea1o ra t\u1eeb \u0111\u1eadu Hà Lan có s\u1ed1 NST trong t\u1ebf bào sinh d\u01b0\u1ee1ng b\u1eb1ng<\/p>","options":["A. 16.","B. 21.","C. 28.","D. 35."],"correct":"1","level":"1","hint":"Th\u1ec3 d\u1ecb b\u1ed9i là hi\u1ec7n t\u01b0\u1ee3ng s\u1ed1 l\u01b0\u1ee3ng nhi\u1ec5m s\u1eafc th\u1ec3 b\u1ecb thay \u0111\u1ed5i \u1edf m\u1ed9t ho\u1eb7c vài c\u1eb7p, nh\u01b0ng không ph\u1ea3i toàn b\u1ed9 b\u1ed9 NST c\u1ee7a loài. Hãy xem xét các d\u1ea1ng d\u1ecb b\u1ed9i ph\u1ed5 bi\u1ebfn nh\u01b0 th\u1ec3 m\u1ed9t (2n-1) ho\u1eb7c th\u1ec3 ba (2n+1) \u0111\u1ec3 tìm \u0111áp án \u0111úng.<\/p>","answer":"\u0110áp án \u0111úng: A. 16.<\/strong><\/p>Th\u1ec3 d\u1ecb b\u1ed9i có s\u1ed1 l\u01b0\u1ee3ng NST thay \u0111\u1ed5i \u1edf m\u1ed9t ho\u1eb7c m\u1ed9t vài c\u1eb7p, ch\u1eb3ng h\u1ea1n nh\u01b0:<\/p>Th\u1ec3 m\u1ed9t (2n-1) = 14 - 1 = 13<\/strong><\/p>Th\u1ec3 ba (2n+1) = 14 + 1 = 15<\/strong><\/p>Trong các \u0111áp án có s\u1ed1 NST cao h\u01a1n 14, ta th\u1ea5y 16<\/strong> có th\u1ec3 xu\u1ea5t phát t\u1eeb th\u1ec3 ba \u1edf hai c\u1eb7p NST (2n+1+1 = 16<\/strong>), \u0111ây là m\u1ed9t d\u1ea1ng d\u1ecb b\u1ed9i h\u1ee3p lý.<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2025-03-28 14:41:36","option_type":"txt","len":0},{"id":"10668","post_id":"8711","mon_id":"1159533","chapter_id":"1159701","question":"Ngô có 2n = 20. Phát bi\u1ec3u nào sau \u0111ây \u0111úng?<\/p>","options":["A. Th\u1ec3 3 nhi\u1ec5m c\u1ee7a ngô có 19 NST.","B. Th\u1ec3 1 nhi\u1ec5m c\u1ee7a ngô có 21 NST.","C. Th\u1ec3 3n c\u1ee7a ngô có 30 NST.","D. Th\u1ec3 4n c\u1ee7a ngô có 38 NST."],"correct":"2","level":"1","hint":"","answer":"\u0110áp án \u0111úng: B. Th\u1ec3 1 nhi\u1ec5m c\u1ee7a ngô có 21 NST.<\/strong><\/p>Ngô có 2n = 20<\/strong>, suy ra:<\/p>Th\u1ec3 3 nhi\u1ec5m (2n + 1) = 21 NST<\/strong> → A sai.<\/p>Th\u1ec3 1 nhi\u1ec5m (2n - 1) = 19 NST<\/strong> → B \u0111úng.<\/p>Th\u1ec3 3n = (3 × 10) = 30 NST<\/strong> → C sai.<\/p>Th\u1ec3 4n = (4 × 10) = 40 NST<\/strong> → D sai.<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2025-03-28 14:43:13","option_type":"txt","len":2},{"id":"10669","post_id":"8711","mon_id":"1159533","chapter_id":"1159701","question":"C\u1ea3i c\u1ee7 có b\u1ed9 NST bình th\u01b0\u1eddng 2n =18. Trong m\u1ed9t t\u1ebf bào sinh d\u01b0\u1ee1ng c\u1ee7a c\u1ee7 c\u1ea3i, ng\u01b0\u1eddi ta \u0111\u1ebfm \u0111\u01b0\u1ee3c 27 NST. \u0110ây là th\u1ec3<\/p>","options":["A. 3 nhi\u1ec5m.","B. tam b\u1ed9i (3n).","C. t\u1ee9 b\u1ed9i (4n).","D. d\u1ecb b\u1ed9i (2n - 1)."],"correct":"2","level":"1","hint":"S\u1ed1 nhi\u1ec5m s\u1eafc th\u1ec3 trong t\u1ebf bào sinh d\u01b0\u1ee1ng có liên quan \u0111\u1ebfn m\u1ee9c \u0111\u1ed9 b\u1ed9i th\u1ec3 c\u1ee7a sinh v\u1eadt. Hãy so sánh s\u1ed1 NST \u0111\u1ebfm \u0111\u01b0\u1ee3c v\u1edbi b\u1ed9 NST bình th\u01b0\u1eddng c\u1ee7a loài (2n = 18) \u0111\u1ec3 xác \u0111\u1ecbnh ki\u1ec3u \u0111\u1ed9t bi\u1ebfn.<\/p>","answer":"\u0110áp án \u0111úng: B. tam b\u1ed9i (3n).<\/strong><\/p>Vì b\u1ed9 NST bình th\u01b0\u1eddng c\u1ee7a c\u1ea3i c\u1ee7 là 2n = 18<\/strong>, n\u1ebfu là th\u1ec3 tam b\u1ed9i (3n) thì s\u1ed1 NST s\u1ebd là 3 × 9 = 27 NST<\/strong>. Do \u0111ó, t\u1ebf bào sinh d\u01b0\u1ee1ng có 27 NST ch\u1ee9ng t\u1ecf cây này thu\u1ed9c th\u1ec3 tam b\u1ed9i.<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2025-03-28 14:44:09","option_type":"txt","len":2}]}