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 24 to 30.
Almost all living things ultimately get their energy from the sun. In a process called photosynthesis, plants, algae, and some other organisms capture the sun's energy and use it to make simple sugars such as glucose. Most other organisms use these organic molecules as a source of energy. Organic materials contain a tremendous amount of energy. As food, they fuel our bodies and those of most other creatures. In such forms as oil, gas, and coal, they heat our homes, run our factories and power our cars.
Photosynthesis begins when solar energy is absorbed by chemicals called photosynthetic pigments that are contained within an organism. The most common photosynthetic pigment is chlorophyll. The bright green color characteristic of plants is caused by it. Most algae have additional pigments that may mask the green chlorophyll. Because of these pigments, algae may be not only green but brown, red, blue or even black.
In a series of enzyme-controlled reactions, the solar energy captured by chlorophyll and other pigments is used to make simple sugars, with carbon dioxide and water as the raw materials. Carbon dioxide is one of very few carbon- containing molecules not considered to be organic compounds. Photosynthesis then converts carbon from an inorganic to an organic form. This is called carbon fixation. In this process, the solar energy that was absorbed by chlorophyll is stored as chemical energy in the form of simple sugars like glucose. The glucose is then used to make other organic compounds. In addition, photosynthesis produces oxygen gas. All the oxygen gas on earth, both in the atmosphere we breathe and in the ocean, was produced by photosynthetic organisms. Photosynthesis constantly replenishes the earth's oxygen supply.
Organisms that are capable of photosynthesis can obtain all the energy they need from sunlight and do not need to eat. They are called autotrophs. Plants are the most familiar autotrophs on land. In the ocean, algae and bacteria are the most important autotrophs. Many organisms cannot produce their own food and must obtain energy by eating organic matter. These are called heterotrophs.
It can be inferred from the passage that the author considers solar energy to be_________.
A. useless to most bacteria and algae
B. a permanent and everlasting source of energy
C. a perfect solution to the energy problem
D. essential for every organism on earth
Chọn D
Câu đề bài: Ta có thể suy ra từ đoạn văn rằng tác giả coi năng lượng mặt trời là _________ .
Đáp án D: cần thiết cho mọi sinh vật trên trái đất Các đáp án còn lại:
A. Vô dụng với hầu hết vi khuẩn và tảo
B. Nguồn năng lượng lâu dài và vĩnh cửu
C. Một giải pháp hoàn hảo cho vấn đề năng lượng
Thông tin trong bài:
Photosynthesis begins when solar energy is absorbed by chemicals called photosynthetic pigments that are contained within an organism. In addition, photosynthesis produces oxygen gas. All the oxygen gas on earth, both in the atmosphere we breathe and in the ocean, was produced by photosynthetic organisms. Photosynthesis constantly replenishes the earth's oxygen supply. - Quá trình quang hợp bắt đầu khi năng lượng mặt trời được hấp thụ bởi các hóa chất gọi là sắc tố quang hợp được chứa trong một sinh vật. Ngoài ra, quang hợp tạo ra khí oxy. Tất cả khí oxy trên trái đất, cả trong khí quyển chúng ta hít thở và trong đại dương, được sinh ra bởi các sinh vật quang hợp. Quang hợp liên tục bổ sung nguồn cung cấp oxy của trái đất