Trong các phương pháp tạo giống sau đây, có bao nhiêu phương pháp có thể tạo ra thế hệ con đồng loạt có kiểu gen giống nhau?

(1) Cấy truyền phô.

(2) Nhân bản vô tính.

(3) Công nghệ gen.

(4) Dung hợp tế bào trần.

(5) Nuôi cấy mô tế bào thực vật trong ống nghiệm.

A. 3.

B. 2.

C. 4.

D. 1.

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each the numbered blanks.

         In some sense, the way we manage our social connections on Facebook is no different from how we build relationships offline. The need for (25) ______ is one of the most basic motivations underlying social behavior. We use Facebook to maintain a positive social identity and satisfy needs for acceptance and social affiliation.

          One study, conducted by researchers in New Zealand, looked into how people weaved Facebook into their daily lives. They were primarily interested in the social dimensions of Facebook, (26) ______ they divided into two categories: direct and indirect actions.

Direct actions include messaging, chat, wall posts, comments, photo tagging, and "likes." Indirect actions are those where an individual looks at a friend's profile or reads that person's status updates. Most Facebook users initiate a combination of direct and indirect actions when they use the website. Some do this quite (27) ______, with nearly a third of users (31%) posting daily status updates.

          The social benefits of using Facebook to communicate with friends and build relationships are mixed. Researchers at Carnegie Mellon University and Facebook analyzed the server logs of more than a thousand Facebook users over a period of two months, and conducted a survey to ask users about how close they feel to their friends, and the frequency with which they make new social connections. They found that Facebook users who engaged (28) ______ greater direct actions (messaging, commenting) reported greater bridging (making new friends), social bonding, and self-esteem. (29) ______, users who had a record of more indirect actions and passive consumption (refreshing the news feed, reading friends' status updates and Viewing their profiles) reported more frequent feelings of loneliness and lower self-esteem.

Điền vào số (26)

A. which    

B. where     

C. that         

D. who

Một quần thể có thành phần kiểu gen là: 0,16AA : 0,48Aa : 0,36aa. Tần số alen a của quần thể này là bao nhiêu?

A. 0,4

B. 0,3

C. 0,5

D. 0,6.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 42.

  One of the most interesting authors of the twentieth century, J.R.R Tolkien, achieved fame through his highly inventive trilogy, The Lord of the Rings. Bom in 1892, Tolkien received his education from Oxford and then served in World War I. After the war, he became a professor of Anglo -Saxon and English language and literature at Oxford University.

  Although published in 1965, the three books that comprise the Lord of the Rings were written in intervals from 1936 to 1949. This was mainly due to Tolkien’s responsibilities as a professor and the outbreak of World War II. By the late 1960s, this fascinating trilogy had become a sociological phenomenon as young people intently studied the mythology and legends created by Tolkien.

  The trilogy is remarkable not only for its highly developed account of historical fiction but also its success as a modem heroic epic. The main plot describes the struggle between good and evil kingdom as they try to acquire a magic ring that has the power to rule the world. The novels, which are set in a time called Middle Earth, describe a detailed fantasy world. Established before humans populated the Earth, Middle Earth was inhabited by good and evil creatures such as hobbits, elves, monsters, wizards, and some humans. The characters and the setting of Middle Earth were modeled after mythological stories from Greece and Northern Europe.

  Although readers have scrutinized the texts for inner meaning and have tried to connect the trilogy with Tolkien’s real life experiences in England during World War II, he denied the connection. He claims that the story began in his years as an undergraduate student and grew out of his desire to create mythology and legends about elves and their language.

  Tolkien was a masterful fantasy novelist who used his extensive knowledge of folklore to create a body of work that is still read and enjoyed throughout the world today.

The word “scrutinized” in the fourth paragraph could be replaced by _____________ .

A. examined

B. denied

C. enjoyed

D. criticized

Biện pháp cải tạo đất : cảnh tác, thuỷ lợi, bón phân.

1.

- khí hậu nước ta là khí hậu nhiệt đới gió mùa, nóng ẩm, mưa nhiều, diễn biến phức tạp.

- Số giờ nắng đạt từ 1400- 3000h trong 1 năm.

- nhiệt độ trung bình năm: trên 21°C.

- mưa lớn từ 1500-2000mm trên năm, độ ẩm không khí cao( trên 80%).

- Nước ta có 4 miền khí hậu:

+ là miền khí hậu phía Bắc , từ dãy Bạch Mã trở ra, mùa Đông lạnh, ít mưa, cuối mùa Đ ẩm ướt, mùa hè nóng và mưa nhiều.

+ Miền khí hậu phía N, từ dãy Bạch Mã trở vào có khí hậu cận xích đạo, nhiệt độ cao quanh năm, có một mùa mưa và một mùa khô tương phản sâu sắc.

+ Miền khí hậu Đông Trường Sơn bao gồm phần lãnh thổ Trung Bộ phía Đông dãy Trường Sơn, từ Hoành Sơn tới Mũi Định, có mưa vào Thu Đông.

+ Khí hậu Biển Đông VN, mạng tính chất gió mùa nhiệt đới hải dương.

2.

-Nước ta có bốn miền khí hậu:

+