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
About fifty years ago, plant physiologists set out to grow roots by themselves in solutions in laboratory flasks. The scientists found that the nutrition of isolated roots was quite simple. They required sugar and the usual minerals and vitamins. However, they did not require organic nitrogen compounds. These roots got along fine on mineral inorganic nitrogen. Roots are capable of making their own proteins and other organic compounds. These activities by roots require energy, of course. The process of respiration uses sugar to make the high energy compound ATP, which drives the biochemical reactions. Respiration also requires oxygen. Highly active roots require a good deal of oxygen.
The study of isolated roots has provided an understanding of the relationship between shoots and roots in intact plants. The leaves of the shoots provide the roots with sugar and vitamins, and the roots provide the shoots with water and minerals. In addition, roots can provide the shoots with organic nitrogen compounds. This comes in handy for the growth of buds in the early spring when leaves are not yet functioning. Once leaves begin photosynthesizing, they produce protein, but only mature leaves can "export" protein to the rest of the plant in the form of amino acids.
Câu 31: Which of the following best describes the organization of the passage?
A. The results of two experiments are compared
B. A generalization is made and several examples of it are given
C. A hypothesis is presented, and several means of providing it are suggested
D. The findings of an experiment are explained
Giải bởi Vietjack
Khoảng năm mươi năm trước, các nhà sinh lý học thực vật bắt đầu tự trồng rễ trong dung dịch trong bình thí nghiệm. Các nhà khoa học phát hiện ra rằng dinh dưỡng của rễ cô lập khá đơn giản. Chúng yêu cầu đường và các khoáng chất và vitamin thông thường. Tuy nhiên, chúng không yêu cầu các hợp chất nitơ hữu cơ. Những rễ này rất thích hợp với nitơ vô cơ khoáng. Rễ có khả năng tự tạo ra protein và các hợp chất hữu cơ khác. Tất nhiên, những hoạt động này của rễ cần năng lượng. Quá trình hô hấp sử dụng đường để tạo ra hợp chất năng lượng cao ATP, thúc đẩy các phản ứng sinh hóa. Quá trình hô hấp cũng cần oxy. Rễ hoạt động mạnh cần nhiều oxy.
Nghiên cứu về rễ cô lập đã cung cấp sự hiểu biết về mối quan hệ giữa chồi và rễ ở cây nguyên vẹn. Lá của chồi cung cấp cho rễ đường và vitamin, rễ cung cấp nước và khoáng cho chồi. Ngoài ra, rễ có thể cung cấp các hợp chất nitơ hữu cơ cho chồi. Điều này rất hữu ích cho sự phát triển của chồi vào đầu mùa xuân khi lá chưa hoạt động. Một khi lá bắt đầu quang hợp, chúng sẽ tạo ra protein, nhưng chỉ những lá trưởng thành mới có thể “xuất khẩu" protein sang phần còn lại của cây dưới dạng. của các axit amin.
31.
Điều nào sau đây mô tả đúng nhất cách tổ chức của đoạn văn?
A. Kết quả của hai thí nghiệm được so sánh với
B. Một tổng quát hóa được thực hiện và một số ví dụ về nó được đưa ra
C. Một giả thuyết được đưa ra và một số phương tiện cung cấp nó được đề xuất
D. Những phát hiện của một thí nghiệm được giải thích
Chọn đáp án D
Gói VIP thi online tại VietJack (chỉ 400k/1 năm học), luyện tập gần 1 triệu câu hỏi có đáp án chi tiết
The farmers and their cattle ________ had been trapped in the storm were fortunately rescued
Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions.
Câu 11:
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase best fits each of the numbered blanks
Around the age of eighteen you must make one of the biggest decisions of your life. Do I stay on at school and hopefully go on to university later? Do I leave and start work or begin a training (3) ________?”
The decision is yours, but it may be (4) ________ remembering two things: there is more unemployment among people who haven't been to university, and people who have the right (5) ______ will have a big advantage in the competition for jobs. If you decide to go straight into a job, there are many opportunities for training. Getting qualifications will help you get on more quickly in many careers, and evening classes allow you to learn (6) ________ you earn. Starting work and taking a break to study when you are older is another possibility. By this way, you can save up money for your student days as well as (7) ______ practical work experience.
Câu 3:
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions
Câu 28: Vietnam exports a lot of rice. It is grown mainly in the south of the country
She applied for training as a pilot, but they turned her down _______ her poor eyesight
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions
Câu 29: The bag was heavy, so we could not take it with us
Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions
Câu 26:
Mark the letter A, B, C, or D on your answer sheet to indicate the indicate the sentence that best combines each pair of sentences in the following questions.
Câu 9: You can go out with your friends. Make sure you finish your homework by 5 p.m
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase best fits each of the numbered blanks
Around the age of eighteen you must make one of the biggest decisions of your life. Do I stay on at school and hopefully go on to university later? Do I leave and start work or begin a training (3) ________?”
The decision is yours, but it may be (4) ________ remembering two things: there is more unemployment among people who haven't been to university, and people who have the right (5) ______ will have a big advantage in the competition for jobs. If you decide to go straight into a job, there are many opportunities for training. Getting qualifications will help you get on more quickly in many careers, and evening classes allow you to learn (6) ________ you earn. Starting work and taking a break to study when you are older is another possibility. By this way, you can save up money for your student days as well as (7) ______ practical work experience.
Câu 6:
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase best fits each of the numbered blanks
Around the age of eighteen you must make one of the biggest decisions of your life. Do I stay on at school and hopefully go on to university later? Do I leave and start work or begin a training (3) ________?”
The decision is yours, but it may be (4) ________ remembering two things: there is more unemployment among people who haven't been to university, and people who have the right (5) ______ will have a big advantage in the competition for jobs. If you decide to go straight into a job, there are many opportunities for training. Getting qualifications will help you get on more quickly in many careers, and evening classes allow you to learn (6) ________ you earn. Starting work and taking a break to study when you are older is another possibility. By this way, you can save up money for your student days as well as (7) ______ practical work experience.
Câu 5:
Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions
Câu 22: Dams are used to control flooding, provide water for irrigation, and generating electricity for the surrounding area
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase best fits each of the numbered blanks
Around the age of eighteen you must make one of the biggest decisions of your life. Do I stay on at school and hopefully go on to university later? Do I leave and start work or begin a training (3) ________?”
The decision is yours, but it may be (4) ________ remembering two things: there is more unemployment among people who haven't been to university, and people who have the right (5) ______ will have a big advantage in the competition for jobs. If you decide to go straight into a job, there are many opportunities for training. Getting qualifications will help you get on more quickly in many careers, and evening classes allow you to learn (6) ________ you earn. Starting work and taking a break to study when you are older is another possibility. By this way, you can save up money for your student days as well as (7) ______ practical work experience.
Câu 4:
Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions
Câu 25:
