Người ta nuôi cấy 8 vi khuẩn E. coli có ADN vùng nhân chỉ chứa N¹⁵ trong môi trường chỉ có N¹⁴. Sau ba thế hệ (tương đương 60 phút nuôi cấy), người ta đưa toàn bộ vi khuẩn được tạo thành sang nuôi cấy trong môi trường chỉ có N¹⁵. Sau một thời gian nuôi cấy tiếp đã tạo ra trong tất cả các vi khuẩn tổng cộng 1936 mạch đơn ADN vùng nhân chứa N¹⁵. Tổng tế bào vi khuẩn thu được ở thời điểm này là:

REDUCED RELATIVE CLAUSES:

1. The next train which leaves the station is to London.

2. The road which connects Hanoi and Ho Chi Minh city is called Number 1

3. The man who sat next to me on the train looked gentle.

4.. The steam engine which was invented by James Watt opened a new period in human

development history.

5. I felt sorry for Paul, who was the only child on the block.

6. The car which is running quickly is red color

7. The boy has a ball which he kicks everyday.

REDUCED RELATIVE CLAUSES:

27. The next train which leaves the station is to London.

28. The road which connects Hanoi and Ho Chi Minh city is called Number 1

29. The man who sat next to me on the train looked gentle.

30. The steam engine which was invented by James Watt opened a new period in human

development history.

31. I felt sorry for Paul, who was the only child on the block.

32. The car which is running quickly is red color

33. The boy has a ball which he kicks everyday.

34. We leam English which we want to have better communication with other people

35.I was born in Hanoi, which is the capital of Vietnam

36. We have an apartment which overlooks the park.

37. The ideas which are presented in that book are interesting.

38. Are national parks good places that can house wild animals?

39. The next question that they will consider is how to clean up the garbage.

40. The noise which comes from the boat engine might disturb sea animals