a. Trong hệ tiêu hóa ở người, khi bị cắt bỏ những cơ quan nào sau đây thì gây ảnh hưởng nghiêm trọng nhất đến quá trình tiêu hóa: dạ dày, túi mật, tụy? Vì sao? b. Sự khác nhau giữa tiêu hóa nội bào và tiêu hóa ngoại bào? Nêu những ưu điểm của tiêu hóa t/ă trong ống tiêu hóa so với trong túi tiêu hóa?

A. Choose the best answer among A, B, C or D to complete each sentence. 1. He was writing to his friend when he __________a noise. A. was hearing B. heard C. had heard D. hears 2. I __________many people since I came here in June. A. met B. has met C. was meeting D. have met 3. We __________ maths at this time last week. A. were learning B. are learning C. was learning D. learnt 4. She was playing games while he __________a football match. A. watched B. watches C. was watching D. watching 5. She __________to Ho Chi Minh city last year. A. goes B. has gone C. go D. went 6. Since we came here, we ______ a lot of acquaintances. A. have had B. had C. have D. are having 7. __________he playing football now? A. Will B. Does C. Was D. Is 8. Every morning, I often sit in my garden and____ to my nightingale sing. A. listening B. listen C. listened D. listens 9. She __________school when she was six. A. start B. started C. has started D. are starting 10. I. __________TV when the telephone rang. A. watched B. was watching C. are watching D. have watched 11. She__________ lunch by the time we arrived. A. had finished B. finished C. have finished D. finishing 12. This record-shop__________ be a book-shop a few years ago. A. used to B. use C. used D. used 13. I couldn't come to the party because I __________go to work. A. have B. had to C. have got D. had 14. Yesterday, I _______ for work late because I _______ to set my alarm. A. had left / forgot B. was leaving / was forgetting C. left / had forgot D. had been leaving / would forget 15. By the time we ____ to the train station, Susan _____ for us for more than two hours. A. will get / has been waiting B. got / was waiting C. got / had been waiting D. get / will wait 16. While her brother was in the army, Sarah ___________ to him twice a week. A. was writing B. wrote C. has written D. had written 17. The Titanic _______ the Atlantic when it _______ an iceberg. A. was crossing / struck B. had crossed / was striking C. crossed / had struck D. is crossing / strikes 18. In the 19th century, it _______ two or three months to cross North America by covered wagon. A. took B. had taken C. had taken D. was taking 19. Last night at this time, they _______ the same thing. She ______ and he ¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬_________ the Newspaper. A. are not doing / is cooking / is reading B. were not doing / was cooking / was reading C. was not doing / has cooked / is reading D. had not done / was cooking /read 20. When I _____ home last night, I ____that Jane ______ a beautiful candlelight dinner. A. had arrived / discovered / prepared B. was arriving / had discovered / was preparing C. have arrived / was discovering / had prepared D. arrived / discovered / was preparing

a. Cấu tạo răng, hàm của trâu phù hợp với loại thức ăn của trâu như thế nào? b. Nêu sự khác biệt cơ bản trong hoạt động tiêu hóa và hấp thụ dinh dưỡng ở ĐV ăn cỏ nhai lại và ĐV ăn cỏ không nhai lại. c. Tại sao trâu, bò đều ăn cỏ nhưng Pr của trâu khác với Pr của bò?

Giúp mình vss!!!!!!!!!!!!!!!!!!

Trong lòng ống tiêu hóa của thú ăn thịt, ở dạ dày luôn duy trì pH thấp (mt axit) còn miệng và ruột đều duy trì pH cao (mt kiềm). Hãy cho biết hiện tượng trên có ý nghĩa gì đối với nhóm ĐV này?

tính chu vi diện tích hình tròn có trong hình bên biết hình vuông có cạnh bằng 10 cm

Vẽ đậu mần siêu cute và show chữ

Giúp mình với ạaaaaaaaaaaaaaaaaaa

Vẽ đậu mần siêu cute và show chữ

giúp mình với và giải thích nữa ạ