Ưu thế lai biểu hiện rõ nhất khi thực hiện phép lai giữa: A. Các cá thể khác loài. B. Các dòng thuần có kiểu gen khác nhau. C. Các cá thể được sinh ra từ một cặp bố mẹ. D. Hoa đực và hoa cái trên cùng một cây. Trong chăn nuôi, người ta sử dụng phương pháp chủ yếu nào để tạo ưu thế lai? A. Giao phối gần. B. Cho F 1 lai với cây P. C Lai khác dòng. D. Lai kinh tế. Ưu thế lai biểu hiện rõ nhất ở con lai của phép lai nào sau đây? A. P: AABbDD X AABbDD. B. P: AaBBDD X Aabbdd. C. P: AAbbDD X aaBBdd. D. P: aabbdd X aabbdd.

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Giải giúp mình với nhé các bạn mk vote năm sao cho Nha Bài 11: Thay thế những động từ in nghiêng trong câu bằng một cụm động từ thích hợp. 1. I don’t like Josh because he often boasts about his wealth. _________ 2. Last month many people in my neighbor had chickenpox. _________ 3. You should reduce the amount you salt in your daily meal. _________ 4. It’s time you confronted your fear and moved on. _________ 5. Yesterday an old friend of mine visited out family. _________ 6. Mary decided to join the cooking contest. _________ 7. I didn’t want to go with him, so I rejected his invitation. _________ 8. They are a well-matched couple and they always agree with each other. _________ 9. When did you start your new hobby? _________ 10. The rain continued all the morning. _________ Bài 12: Hoàn thành các câu dưới đây bằng cách điền từ thích hợp vào chỗ trống. 1. Peter always look ____________ his senior colleagues. 2. Mary is going ____________ a singing competition. 3. Nothing can make ____________ the loss of my cat. 4. Jim didn’t work yesterday because he came ____________ flu. 5. My mother always reminds me to stay ____________ bad people. 6. As a child I used to wait ____________ the present from Santa Clause. 7. I can’t ____________ put his selfishness any more. 8. They argue a lot, They seem to never get ____________ each other. 9. Last year she went ____________ an operation. 10. Last week we got ____________ all the old furniture and bought new one. Bài 13: Gạch chân lỗi sai trong câu và viết lại câu đúng. _____ 1. Although she didn’t warm up carefully before running, her leg was hurt during the race. _____ 2. Everyone dressed up though they wanted to be the King or Queen of the prom. _____ 3. Since I am really interested in lacquerware, I rarely buy one for me. _____ 4. As though my brother and I don’t get on well, we still care about the other. _____ 5. What would you do unless you won a lottery? _____ 6. Mr. Smith is renowned artisan. Everyone looks down on him. _____ 7. While I came home, my cat was sleeping on the sofa. _____ 8. Because Peter cheated on me, I wouldn’t get back on him.