Protein và enzyme

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{"common":{"save":0,"post_id":"10157","level":1,"total":10,"point":10,"point_extra":0},"segment":[{"id":"9207","post_id":"10157","mon_id":"1160346","chapter_id":"1160215","question":"Phát bi\u1ec3u nào sau \u0111ây sai?<\/p>","options":["A. Tripeptide Gly–Ala–Gly có ph\u1ea3n \u1ee9ng màu biuret v\u1edbi Cu(OH)\u2082\/OH\u207b.","B. Protein \u0111\u01a1n gi\u1ea3n \u0111\u01b0\u1ee3c t\u1ea1o thành t\u1eeb các g\u1ed1c α–amino acid.","C. T\u1ea5t c\u1ea3 các peptide \u0111\u1ec1u có kh\u1ea3 n\u0103ng tham gia ph\u1ea3n \u1ee9ng th\u1ee7y phân.","D. Trong phân t\u1eed dipeptide m\u1ea1ch h\u1edf có hai liên k\u1ebft peptide."],"correct":"4","level":"1","hint":"G\u1ee3i ý: Hãy nh\u1edb r\u1eb1ng s\u1ed1 liên k\u1ebft peptit = s\u1ed1 g\u1ed1c amino acid – 1<\/strong>. Vì v\u1eady, dipeptit (g\u1ed3m 2 g\u1ed1c amino acid) ch\u1ec9 có 1 liên k\u1ebft peptit<\/strong>.<\/p>","answer":"\u0110áp án \u0111úng: D. Trong phân t\u1eed dipeptit m\u1ea1ch h\u1edf có hai liên k\u1ebft peptit.<\/strong><\/span><\/p>Gi\u1ea3i thích:<\/p><ul data-end=\"801\" data-start=\"231\"> <li data-end=\"402\" data-start=\"231\">A \u0111úng:<\/strong> Tripeptit Gly–Ala–Gly<\/strong> có 2 liên k\u1ebft peptit<\/strong>, nên có ph\u1ea3n \u1ee9ng màu biuret<\/strong> v\u1edbi Cu(OH)\u2082 trong môi tr\u01b0\u1eddng ki\u1ec1m<\/strong>, t\u1ea1o màu tím \u0111\u1eb7c tr\u01b0ng<\/strong> → \u0111úng.<\/p><\/li> <li data-end=\"525\" data-start=\"403\">B \u0111úng:<\/strong> Protein \u0111\u01a1n gi\u1ea3n<\/strong> \u0111\u01b0\u1ee3c c\u1ea5u t\u1ea1o ch\u1ec9 t\u1eeb các g\u1ed1c α–amino acid<\/strong>, không có thành ph\u1ea7n phi protein → \u0111úng.<\/p><\/li> <li data-end=\"668\" data-start=\"526\">C \u0111úng:<\/strong> T\u1ea5t c\u1ea3 peptit<\/strong> (dù là di-, tri- hay polypeptit) \u0111\u1ec1u b\u1ecb th\u1ee7y phân<\/strong> trong môi tr\u01b0\u1eddng acid ho\u1eb7c base (khi \u0111un nóng) → \u0111úng.<\/p><\/li> <li data-end=\"801\" data-start=\"669\">D sai:<\/strong> Dipeptit<\/strong> \u0111\u01b0\u1ee3c t\u1ea1o b\u1edfi 2 g\u1ed1c α–amino acid<\/strong>, nên ch\u1ec9 có 1 liên k\u1ebft peptit<\/strong>, không ph\u1ea3i 2 → phát bi\u1ec3u sai<\/strong>.<\/p><\/li><\/ul>","type":"choose","extra_type":"classic","user_id":"139","test":"0","date":"2025-11-01 09:33:11","option_type":"txt","len":3},{"id":"9208","post_id":"10157","mon_id":"1160346","chapter_id":"1160215","question":"Khi cho n\u01b0\u1edbc chanh vào s\u1eefa bò có hi\u1ec7n t\u01b0\u1ee3ng<\/p>","options":["A. s\u1eefa bò b\u1ecb vón c\u1ee5c.","B. s\u1eefa bò và n\u01b0\u1edbc chanh hòa tan vào nhau.","C. xu\u1ea5t hi\u1ec7n màu xanh \u0111\u1eb7c tr\u01b0ng.","D. không có hi\u1ec7n t\u01b0\u1ee3ng gì."],"correct":"1","level":"1","hint":"G\u1ee3i ý: S\u1eefa bò ch\u1ee9a protein (ch\u1ee7 y\u1ebfu là casein)<\/strong> – ch\u1ea5t này d\u1ec5 b\u1ecb \u0111ông t\u1ee5 khi g\u1eb7p môi tr\u01b0\u1eddng axit<\/strong>.<\/p>","answer":"\u0110áp án \u0111úng: A. S\u1eefa bò b\u1ecb vón c\u1ee5c.<\/strong><\/span><\/p>Gi\u1ea3i thích:<\/p><ul data-end=\"469\" data-start=\"162\"> <li data-end=\"259\" data-start=\"162\">Trong s\u1eefa<\/strong> có protein casein<\/strong> t\u1ed3n t\u1ea1i d\u1ea1ng keo \u1ed5n \u0111\u1ecbnh trong môi tr\u01b0\u1eddng g\u1ea7n trung tính.<\/p><\/li> <li data-end=\"398\" data-start=\"260\">N\u01b0\u1edbc chanh<\/strong> ch\u1ee9a axit citric (C\u2086H\u2088O\u2087)<\/strong> → khi cho vào s\u1eefa, pH gi\u1ea3m → protein b\u1ecb bi\u1ebfn tính và \u0111ông t\u1ee5<\/strong>, t\u1ea1o m\u1ea3ng vón tr\u1eafng<\/strong>.<\/p><\/li> <li data-end=\"469\" data-start=\"399\">Hi\u1ec7n t\u01b0\u1ee3ng này chính là s\u1ef1 \u0111ông t\u1ee5 protein b\u1edfi s\u1ef1 thay \u0111\u1ed5i pH<\/strong>.<\/p><\/li> <li data-end=\"469\" data-start=\"399\">→ Các \u0111áp án khác sai:<\/p><\/li> <li data-end=\"538\" data-start=\"496\">B:<\/strong> Không tan, mà b\u1ecb \u0111ông t\u1ee5 → sai.<\/p><\/li> <li data-end=\"587\" data-start=\"539\">C:<\/strong> Không có ph\u1ea3n \u1ee9ng t\u1ea1o màu xanh → sai.<\/p><\/li> <li data-end=\"627\" data-start=\"588\">D:<\/strong> Có hi\u1ec7n t\u01b0\u1ee3ng rõ ràng → sai.<\/p><\/li><\/ul>","type":"choose","extra_type":"classic","user_id":"139","test":"0","date":"2025-11-01 09:45:52","option_type":"txt","len":3},{"id":"9209","post_id":"10157","mon_id":"1160346","chapter_id":"1160215","question":"Khi th\u1ee7y phân hoàn toàn 500 gam protein X thì thu \u0111\u01b0\u1ee3c 178 gam alanine. N\u1ebfu kh\u1ed1i l\u01b0\u1ee3ng phân t\u1eed c\u1ee7a X là 50 000 amu thì s\u1ed1 m\u1eaft xích alanine trong phân t\u1eed X là<\/p>","options":["A. 100.","B. 178.","C. 500.","D. 200"],"correct":"4","level":"1","hint":"G\u1ee3i ý: Hãy so sánh s\u1ed1 mol protein<\/strong> và s\u1ed1 mol alanine thu \u0111\u01b0\u1ee3c khi th\u1ee7y phân<\/strong>, t\u1eeb \u0111ó tìm xem 1 mol protein t\u1ea1o ra bao nhiêu mol alanine<\/strong> → chính là s\u1ed1 m\u1eaft xích alanine<\/strong> trong phân t\u1eed.<\/p>","answer":"\u0110áp án: D. 200<\/span><\/strong><\/p>Gi\u1ea3i thích:<\/strong> 500 g X → 0,01 mol X 178 g Ala → 2 mol Ala → 1 mol X cho 2 \/ 0,01 = 200 mol Ala<\/strong> ⇒ Có 200 m\u1eaft xích alanine<\/strong>.<\/p>","type":"choose","extra_type":"classic","user_id":"139","test":"0","date":"2025-11-01 09:47:52","option_type":"txt","len":0}]}