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  * 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.   (Hooked on TOEFL Reading - LinguaForum From the passage, we can see that___________.
* 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. (Hooked on TOEFL Reading - LinguaForum Which of the following is NOT true?
* 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.   Thirty years ago, Lake Ponkapog in Hartwell, New Jersey, was full of life. Many birds and animals lived beside the water, which was full of fish. Now there are few birds, animals, and fish. The lake water is polluted. It is a dirty brown colour, and it is filled with strange plants.   How did this happen? First, we must think about how water gets into Lake Ponkapog. When it rains, water comes into the lake from all around. In the past, there were woods all around Lake Ponkapog, so the rainwater was clean.   Now there are many homes on the lake shore. People often use the chemicals in their gardens. They use other chemicals inside their houses for cleaning and killing insects. There are also many businesses. Businesses use chemicals in their machines or stores. Other chemicals fall onto the ground from cars or trucks. When it rains, the rainwater flows by these homes and businesses. It picks up all the chemicals and then pours them into the lake. They pollute the water and kill the animal life.   There is still another problem at the lake: exotic plants. These plants come from other countries. They have no natural enemies here, and they grow very quickly. In a short time, they can fill up a lake. Then there is no room for other plants. The plants that normally grow there die. These plants gave many animals and fish their foods or their homes. So now those animals and fish die, too.   People in Hartwell are worried. They love their lake and want to save it. Will it be possible? A clean lake must have clean rainwater going into it. Clean rainwater is possible only if people are more careful about chemicals at home and at work. They must also be more careful about gas and oil and other chemicals on the ground. (“Reading Power ” by Beatrice S. Mikulecky/Linda Jeffries - Longman)  Exotic plants grow quickly because they___________.    
* 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.   Thirty years ago, Lake Ponkapog in Hartwell, New Jersey, was full of life. Many birds and animals lived beside the water, which was full of fish. Now there are few birds, animals, and fish. The lake water is polluted. It is a dirty brown colour, and it is filled with strange plants.   How did this happen? First, we must think about how water gets into Lake Ponkapog. When it rains, water comes into the lake from all around. In the past, there were woods all around Lake Ponkapog, so the rainwater was clean.   Now there are many homes on the lake shore. People often use the chemicals in their gardens. They use other chemicals inside their houses for cleaning and killing insects. There are also many businesses. Businesses use chemicals in their machines or stores. Other chemicals fall onto the ground from cars or trucks. When it rains, the rainwater flows by these homes and businesses. It picks up all the chemicals and then pours them into the lake. They pollute the water and kill the animal life.   There is still another problem at the lake: exotic plants. These plants come from other countries. They have no natural enemies here, and they grow very quickly. In a short time, they can fill up a lake. Then there is no room for other plants. The plants that normally grow there die. These plants gave many animals and fish their foods or their homes. So now those animals and fish die, too.   People in Hartwell are worried. They love their lake and want to save it. Will it be possible? A clean lake must have clean rainwater going into it. Clean rainwater is possible only if people are more careful about chemicals at home and at work. They must also be more careful about gas and oil and other chemicals on the ground. (“Reading Power ” by Beatrice S. Mikulecky/Linda Jeffries - Longman)  In the past, the water in Lake Ponkapog was made clean by____________.    
* 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.   Thirty years ago, Lake Ponkapog in Hartwell, New Jersey, was full of life. Many birds and animals lived beside the water, which was full of fish. Now there are few birds, animals, and fish. The lake water is polluted. It is a dirty brown colour, and it is filled with strange plants.   How did this happen? First, we must think about how water gets into Lake Ponkapog. When it rains, water comes into the lake from all around. In the past, there were woods all around Lake Ponkapog, so the rainwater was clean.   Now there are many homes on the lake shore. People often use the chemicals in their gardens. They use other chemicals inside their houses for cleaning and killing insects. There are also many businesses. Businesses use chemicals in their machines or stores. Other chemicals fall onto the ground from cars or trucks. When it rains, the rainwater flows by these homes and businesses. It picks up all the chemicals and then pours them into the lake. They pollute the water and kill the animal life.   There is still another problem at the lake: exotic plants. These plants come from other countries. They have no natural enemies here, and they grow very quickly. In a short time, they can fill up a lake. Then there is no room for other plants. The plants that normally grow there die. These plants gave many animals and fish their foods or their homes. So now those animals and fish die, too.   People in Hartwell are worried. They love their lake and want to save it. Will it be possible? A clean lake must have clean rainwater going into it. Clean rainwater is possible only if people are more careful about chemicals at home and at work. They must also be more careful about gas and oil and other chemicals on the ground. (“Reading Power ” by Beatrice S. Mikulecky/Linda Jeffries - Longman) This article is about____________.
* 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 43 to 50.   “They told me I could never walk again. But when I listened to music, I forgot all about the pain. I found the strength I didn’t know I had.”Ninety-two-year-old Tina Goodman, who regained her ability to walk, thanks to music.   This is just one of the many stories in Fettaro’s book “The Healing Power of Music” . Fettaro tries to show just how important music is in our lives and how it can help us to be healthy and happy.   According to Fettaro, music can make sick people again. In fact, his book comes with a CD of recordings, each one specially designed to help with a number of health problems.   Fettaro, e well-known music therapist, promises that by reading his book, you will be able to develop the healing power of music in your life. He says this will help you fight headaches and back pain, as well as reduce stress, high blood pressure, and many other common illnesses.   Certainly, I accept that listening to certain types of music can help with particular problems, such as stress. I am also comfortable with Fettaro’s claim that by reading his book, you’ll be able to create a peaceful enviroment to help you relax in your home. I found the relaxation and breathing techniques very useful. Similarly his claim that music help you sleep better seems reasonable. Yet when he goes on to promise his music therapies will help cure depression and even cancer, he begins to sound a little bit unbelievable.   Nevertheless, for those of you who are interested in the power of music to heal, this is a great book to buy. It’s a thorough introduction to the history and practice of music therapy. Fettaro writes in a simple, easy to understand way and shows clearly how music can affect us positively. His basic message-that music can improve our lives-is well-presented and clear. It may even be true that certain techniques covered here can help some people recover from unpleasant health problems. However, his promises of “amazing results” seem impossible to justify.     Which word is similar to the word “justify”?
* 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 43 to 50.   “They told me I could never walk again. But when I listened to music, I forgot all about the pain. I found the strength I didn’t know I had.”Ninety-two-year-old Tina Goodman, who regained her ability to walk, thanks to music.   This is just one of the many stories in Fettaro’s book “The Healing Power of Music” . Fettaro tries to show just how important music is in our lives and how it can help us to be healthy and happy.   According to Fettaro, music can make sick people again. In fact, his book comes with a CD of recordings, each one specially designed to help with a number of health problems.   Fettaro, e well-known music therapist, promises that by reading his book, you will be able to develop the healing power of music in your life. He says this will help you fight headaches and back pain, as well as reduce stress, high blood pressure, and many other common illnesses.   Certainly, I accept that listening to certain types of music can help with particular problems, such as stress. I am also comfortable with Fettaro’s claim that by reading his book, you’ll be able to create a peaceful enviroment to help you relax in your home. I found the relaxation and breathing techniques very useful. Similarly his claim that music help you sleep better seems reasonable. Yet when he goes on to promise his music therapies will help cure depression and even cancer, he begins to sound a little bit unbelievable.   Nevertheless, for those of you who are interested in the power of music to heal, this is a great book to buy. It’s a thorough introduction to the history and practice of music therapy. Fettaro writes in a simple, easy to understand way and shows clearly how music can affect us positively. His basic message-that music can improve our lives-is well-presented and clear. It may even be true that certain techniques covered here can help some people recover from unpleasant health problems. However, his promises of “amazing results” seem impossible to justify.     What is the writer’s opinion of the book?
* 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 43 to 50.   “They told me I could never walk again. But when I listened to music, I forgot all about the pain. I found the strength I didn’t know I had.”Ninety-two-year-old Tina Goodman, who regained her ability to walk, thanks to music.   This is just one of the many stories in Fettaro’s book “The Healing Power of Music” . Fettaro tries to show just how important music is in our lives and how it can help us to be healthy and happy.   According to Fettaro, music can make sick people again. In fact, his book comes with a CD of recordings, each one specially designed to help with a number of health problems.   Fettaro, e well-known music therapist, promises that by reading his book, you will be able to develop the healing power of music in your life. He says this will help you fight headaches and back pain, as well as reduce stress, high blood pressure, and many other common illnesses.   Certainly, I accept that listening to certain types of music can help with particular problems, such as stress. I am also comfortable with Fettaro’s claim that by reading his book, you’ll be able to create a peaceful enviroment to help you relax in your home. I found the relaxation and breathing techniques very useful. Similarly his claim that music help you sleep better seems reasonable. Yet when he goes on to promise his music therapies will help cure depression and even cancer, he begins to sound a little bit unbelievable.   Nevertheless, for those of you who are interested in the power of music to heal, this is a great book to buy. It’s a thorough introduction to the history and practice of music therapy. Fettaro writes in a simple, easy to understand way and shows clearly how music can affect us positively. His basic message-that music can improve our lives-is well-presented and clear. It may even be true that certain techniques covered here can help some people recover from unpleasant health problems. However, his promises of “amazing results” seem impossible to justify. Which is not stated by Fettaro as curable?
* 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 43 to 50.   “They told me I could never walk again. But when I listened to music, I forgot all about the pain. I found the strength I didn’t know I had.”Ninety-two-year-old Tina Goodman, who regained her ability to walk, thanks to music.   This is just one of the many stories in Fettaro’s book “The Healing Power of Music” . Fettaro tries to show just how important music is in our lives and how it can help us to be healthy and happy.   According to Fettaro, music can make sick people again. In fact, his book comes with a CD of recordings, each one specially designed to help with a number of health problems.   Fettaro, e well-known music therapist, promises that by reading his book, you will be able to develop the healing power of music in your life. He says this will help you fight headaches and back pain, as well as reduce stress, high blood pressure, and many other common illnesses.   Certainly, I accept that listening to certain types of music can help with particular problems, such as stress. I am also comfortable with Fettaro’s claim that by reading his book, you’ll be able to create a peaceful enviroment to help you relax in your home. I found the relaxation and breathing techniques very useful. Similarly his claim that music help you sleep better seems reasonable. Yet when he goes on to promise his music therapies will help cure depression and even cancer, he begins to sound a little bit unbelievable.   Nevertheless, for those of you who are interested in the power of music to heal, this is a great book to buy. It’s a thorough introduction to the history and practice of music therapy. Fettaro writes in a simple, easy to understand way and shows clearly how music can affect us positively. His basic message-that music can improve our lives-is well-presented and clear. It may even be true that certain techniques covered here can help some people recover from unpleasant health problems. However, his promises of “amazing results” seem impossible to justify.  What are the two techniques useful to the writer?    
* 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 43 to 50.   “They told me I could never walk again. But when I listened to music, I forgot all about the pain. I found the strength I didn’t know I had.”Ninety-two-year-old Tina Goodman, who regained her ability to walk, thanks to music.   This is just one of the many stories in Fettaro’s book “The Healing Power of Music” . Fettaro tries to show just how important music is in our lives and how it can help us to be healthy and happy.   According to Fettaro, music can make sick people again. In fact, his book comes with a CD of recordings, each one specially designed to help with a number of health problems.   Fettaro, e well-known music therapist, promises that by reading his book, you will be able to develop the healing power of music in your life. He says this will help you fight headaches and back pain, as well as reduce stress, high blood pressure, and many other common illnesses.   Certainly, I accept that listening to certain types of music can help with particular problems, such as stress. I am also comfortable with Fettaro’s claim that by reading his book, you’ll be able to create a peaceful enviroment to help you relax in your home. I found the relaxation and breathing techniques very useful. Similarly his claim that music help you sleep better seems reasonable. Yet when he goes on to promise his music therapies will help cure depression and even cancer, he begins to sound a little bit unbelievable.   Nevertheless, for those of you who are interested in the power of music to heal, this is a great book to buy. It’s a thorough introduction to the history and practice of music therapy. Fettaro writes in a simple, easy to understand way and shows clearly how music can affect us positively. His basic message-that music can improve our lives-is well-presented and clear. It may even be true that certain techniques covered here can help some people recover from unpleasant health problems. However, his promises of “amazing results” seem impossible to justify.  What is the basic message of Fettaro’s book?    
* 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 43 to 50.   “They told me I could never walk again. But when I listened to music, I forgot all about the pain. I found the strength I didn’t know I had.”Ninety-two-year-old Tina Goodman, who regained her ability to walk, thanks to music.   This is just one of the many stories in Fettaro’s book “The Healing Power of Music” . Fettaro tries to show just how important music is in our lives and how it can help us to be healthy and happy.   According to Fettaro, music can make sick people again. In fact, his book comes with a CD of recordings, each one specially designed to help with a number of health problems.   Fettaro, e well-known music therapist, promises that by reading his book, you will be able to develop the healing power of music in your life. He says this will help you fight headaches and back pain, as well as reduce stress, high blood pressure, and many other common illnesses.   Certainly, I accept that listening to certain types of music can help with particular problems, such as stress. I am also comfortable with Fettaro’s claim that by reading his book, you’ll be able to create a peaceful enviroment to help you relax in your home. I found the relaxation and breathing techniques very useful. Similarly his claim that music help you sleep better seems reasonable. Yet when he goes on to promise his music therapies will help cure depression and even cancer, he begins to sound a little bit unbelievable.   Nevertheless, for those of you who are interested in the power of music to heal, this is a great book to buy. It’s a thorough introduction to the history and practice of music therapy. Fettaro writes in a simple, easy to understand way and shows clearly how music can affect us positively. His basic message-that music can improve our lives-is well-presented and clear. It may even be true that certain techniques covered here can help some people recover from unpleasant health problems. However, his promises of “amazing results” seem impossible to justify.   Which statement is not true?
* 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.   (Hooked on TOEFL Reading - LinguaForum It can be inferred from the passage that the author considers solar energy to be_________.
* 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.   (Hooked on TOEFL Reading - LinguaForum Which of the following is true about heterotrophs?  
* 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. (Hooked on TOEFL Reading - LinguaForum Based on the information in paragraph 3, we can see that glucose________.
* 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. (Hooked on TOEFL Reading - LinguaForum) The word “fuel” in the first paragraph is similar in meaning to_________.