TASK 1 (PROCESS/ DIAGRAM): DOLLY THE SHEEP

The diagram shows the process by which sheep embryos are cloned. Summarise the information by selecting and reporting the main features. Write at least 150 words.

Sample Answer

The diagram illustrates the process of cloning a sheep embryo through somatic cell nuclear transfer.

The procedure involves six distinct stages, beginning with the extraction of cells from two female sheep and culminating in the birth of a genetically identical lamb. Initially, a body cell is taken from Sheep A, which serves as the genetic donor. Simultaneously, an egg cell is collected from Sheep B, and its nucleus—containing its genetic material—is carefully removed to create an enucleated egg.

Next, the DNA from Sheep A’s body cell is inserted into the enucleated egg from Sheep B. This fusion results in a single cell that contains the complete genetic information of Sheep A. The fused cell is then stimulated to develop into an embryo through biochemical activation.

Once the embryo reaches a suitable developmental stage, it is implanted into the uterus of a third sheep, Sheep C, who acts as the surrogate mother. Eventually, this sheep gives birth to a lamb that is a clone of Sheep A, sharing identical genetic characteristics.

Vocabulary

1. cloning a sheep embryo – nhân bản phôi cừu
2. somatic cell nuclear transfer – chuyển nhân tế bào soma
3. six distinct stages – sáu giai đoạn riêng biệt
4. extraction of cells – tách tế bào
5. culminating in the birth – kết thúc bằng sự ra đời
6. genetically identical lamb – con cừu giống hệt về mặt di truyền
7. body cell – tế bào cơ thể
8. genetic donor – nguồn hiến gen
9. egg cell – tế bào trứng
10. nucleus—containing its genetic material— – nhân chứa vật chất di truyền
11. enucleated egg – trứng đã loại bỏ nhân
12. DNA – ADN
13. inserted into – được đưa vào
14. fusion results in – sự kết hợp dẫn đến
15. complete genetic information – thông tin di truyền đầy đủ
16. fused cell – tế bào hợp nhất
17. stimulated to develop – kích thích phát triển
18. biochemical activation – kích hoạt sinh hóa
19. suitable developmental stage – giai đoạn phát triển thích hợp
20. implanted into the uterus – cấy vào tử cung
21. surrogate mother – mẹ mang thai hộ
22. gives birth to – sinh ra
23. clone of Sheep A – bản sao của Cừu A
24. identical genetic characteristics – đặc điểm di truyền giống hệt
25. genetic material – vật chất di truyền