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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 for the question. Tides are the periodic rise and fall of the Earth’s waters that are caused by the Moon’s and Sun’s forces of gravity acting on the Earth .It is important to distinguish natural tidal phenomena from huge tsunamis , with the latter being caused by earthquakes and undersea volcanic eruptions. The Moon is a main factor controlling ordinary tides. At the location on the Earth closest to the Moon, it exerts a powerful gravitational pull on the water. The resulting rise in the water produces higher tides. The water on the side of the Earth farthest away from the Moon also gets pulled by this lunar gravity, but not as strongly. The Earth itself has its own gravitational force that is constantly pulling waters downward, which is why the oceans do not simply bulge out toward the Moon. Ordinary tides usually feature high and low waters alternating in relation to the Earth’s rotation. Most shores around the world have high waters and two low waters for each day, which last about 24 hours and 50 minutes. The difference in height between the high water and low water is called the range of tide, and it can be quite dramatic in narrower bays .Canada’s bays of Fundy , for example , commonly experiences the world’s most extreme tidal ranges , with daily differences of the 16 meters. Two other types of tides are influenced by the Sun, which is much farther away from the Earth and exerts less than half of the Moon’s gravitational force. When the Sun, the Moon and the Earth are directly in line, the solar and lunar gravitational forces add up to produce higher spring tides. The range of spring tides is intensified, with higher water marks and lower low water marks. However, when the Moon is in the first or third quarter, it is at a 90–degree angle with the Sun in relation to the Earth .The opposing solar and lunar forces partially cancel each other out, and the result is a lower tide. This is called a neap tide, which comes twice a month and has lower high water marks and higher low water marks. The range of neap tides is minimum. Some tides do not occur over water at all. The solid body of the Earth has slight elasticity, so lunar and solar gravity cause it to stretch very subtly. These changes in the Earth’s shape, although imperceptible to humans, are known as Earth tides. Another tidal phenomenon, atmospheric tides, is caused by the Sun’s heating of the Earth’s atmosphere. Like ordinary tides, they usually occur over 12–hour periods. What is true about the Moon’s gravitational force? 

Xem chi tiết 767 lượt xem 6 năm trước

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the question. Tides are the periodic rise and fall of the Earth’s waters that are caused by the Moon’s and Sun’s forces of gravity acting on the Earth .It is important to distinguish natural tidal phenomena from huge tsunamis , with the latter being caused by earthquakes and undersea volcanic eruptions. The Moon is a main factor controlling ordinary tides. At the location on the Earth closest to the Moon, it exerts a powerful gravitational pull on the water. The resulting rise in the water produces higher tides. The water on the side of the Earth farthest away from the Moon also gets pulled by this lunar gravity, but not as strongly. The Earth itself has its own gravitational force that is constantly pulling waters downward, which is why the oceans do not simply bulge out toward the Moon. Ordinary tides usually feature high and low waters alternating in relation to the Earth’s rotation. Most shores around the world have high waters and two low waters for each day, which last about 24 hours and 50 minutes. The difference in height between the high water and low water is called the range of tide, and it can be quite dramatic in narrower bays .Canada’s bays of Fundy , for example , commonly experiences the world’s most extreme tidal ranges , with daily differences of the 16 meters. Two other types of tides are influenced by the Sun, which is much farther away from the Earth and exerts less than half of the Moon’s gravitational force. When the Sun, the Moon and the Earth are directly in line, the solar and lunar gravitational forces add up to produce higher spring tides. The range of spring tides is intensified, with higher water marks and lower low water marks. However, when the Moon is in the first or third quarter, it is at a 90–degree angle with the Sun in relation to the Earth .The opposing solar and lunar forces partially cancel each other out, and the result is a lower tide. This is called a neap tide, which comes twice a month and has lower high water marks and higher low water marks. The range of neap tides is minimum. Some tides do not occur over water at all. The solid body of the Earth has slight elasticity, so lunar and solar gravity cause it to stretch very subtly. These changes in the Earth’s shape, although imperceptible to humans, are known as Earth tides. Another tidal phenomenon, atmospheric tides, is caused by the Sun’s heating of the Earth’s atmosphere. Like ordinary tides, they usually occur over 12–hour periods. The word imperceptible in the last paragraph could best be replace by

Xem chi tiết 452 lượt xem 6 năm trước

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the question. Tides are the periodic rise and fall of the Earth’s waters that are caused by the Moon’s and Sun’s forces of gravity acting on the Earth .It is important to distinguish natural tidal phenomena from huge tsunamis , with the latter being caused by earthquakes and undersea volcanic eruptions. The Moon is a main factor controlling ordinary tides. At the location on the Earth closest to the Moon, it exerts a powerful gravitational pull on the water. The resulting rise in the water produces higher tides. The water on the side of the Earth farthest away from the Moon also gets pulled by this lunar gravity, but not as strongly. The Earth itself has its own gravitational force that is constantly pulling waters downward, which is why the oceans do not simply bulge out toward the Moon. Ordinary tides usually feature high and low waters alternating in relation to the Earth’s rotation. Most shores around the world have high waters and two low waters for each day, which last about 24 hours and 50 minutes. The difference in height between the high water and low water is called the range of tide, and it can be quite dramatic in narrower bays .Canada’s bays of Fundy , for example , commonly experiences the world’s most extreme tidal ranges , with daily differences of the 16 meters. Two other types of tides are influenced by the Sun, which is much farther away from the Earth and exerts less than half of the Moon’s gravitational force. When the Sun, the Moon and the Earth are directly in line, the solar and lunar gravitational forces add up to produce higher spring tides. The range of spring tides is intensified, with higher water marks and lower low water marks. However, when the Moon is in the first or third quarter, it is at a 90–degree angle with the Sun in relation to the Earth .The opposing solar and lunar forces partially cancel each other out, and the result is a lower tide. This is called a neap tide, which comes twice a month and has lower high water marks and higher low water marks. The range of neap tides is minimum. Some tides do not occur over water at all. The solid body of the Earth has slight elasticity, so lunar and solar gravity cause it to stretch very subtly. These changes in the Earth’s shape, although imperceptible to humans, are known as Earth tides. Another tidal phenomenon, atmospheric tides, is caused by the Sun’s heating of the Earth’s atmosphere. Like ordinary tides, they usually occur over 12–hour periods. What can be inferred about Canada’s Bay of Fundy ? 

Xem chi tiết 819 lượt xem 6 năm trước

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the question. Tides are the periodic rise and fall of the Earth’s waters that are caused by the Moon’s and Sun’s forces of gravity acting on the Earth .It is important to distinguish natural tidal phenomena from huge tsunamis , with the latter being caused by earthquakes and undersea volcanic eruptions. The Moon is a main factor controlling ordinary tides. At the location on the Earth closest to the Moon, it exerts a powerful gravitational pull on the water. The resulting rise in the water produces higher tides. The water on the side of the Earth farthest away from the Moon also gets pulled by this lunar gravity, but not as strongly. The Earth itself has its own gravitational force that is constantly pulling waters downward, which is why the oceans do not simply bulge out toward the Moon. Ordinary tides usually feature high and low waters alternating in relation to the Earth’s rotation. Most shores around the world have high waters and two low waters for each day, which last about 24 hours and 50 minutes. The difference in height between the high water and low water is called the range of tide, and it can be quite dramatic in narrower bays .Canada’s bays of Fundy , for example , commonly experiences the world’s most extreme tidal ranges , with daily differences of the 16 meters. Two other types of tides are influenced by the Sun, which is much farther away from the Earth and exerts less than half of the Moon’s gravitational force. When the Sun, the Moon and the Earth are directly in line, the solar and lunar gravitational forces add up to produce higher spring tides. The range of spring tides is intensified, with higher water marks and lower low water marks. However, when the Moon is in the first or third quarter, it is at a 90–degree angle with the Sun in relation to the Earth .The opposing solar and lunar forces partially cancel each other out, and the result is a lower tide. This is called a neap tide, which comes twice a month and has lower high water marks and higher low water marks. The range of neap tides is minimum. Some tides do not occur over water at all. The solid body of the Earth has slight elasticity, so lunar and solar gravity cause it to stretch very subtly. These changes in the Earth’s shape, although imperceptible to humans, are known as Earth tides. Another tidal phenomenon, atmospheric tides, is caused by the Sun’s heating of the Earth’s atmosphere. Like ordinary tides, they usually occur over 12–hour periods. The word exerts in paragraph 2 is closest in meaning to

Xem chi tiết 1.3 K lượt xem 6 năm trước

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the question. Tides are the periodic rise and fall of the Earth’s waters that are caused by the Moon’s and Sun’s forces of gravity acting on the Earth .It is important to distinguish natural tidal phenomena from huge tsunamis , with the latter being caused by earthquakes and undersea volcanic eruptions. The Moon is a main factor controlling ordinary tides. At the location on the Earth closest to the Moon, it exerts a powerful gravitational pull on the water. The resulting rise in the water produces higher tides. The water on the side of the Earth farthest away from the Moon also gets pulled by this lunar gravity, but not as strongly. The Earth itself has its own gravitational force that is constantly pulling waters downward, which is why the oceans do not simply bulge out toward the Moon. Ordinary tides usually feature high and low waters alternating in relation to the Earth’s rotation. Most shores around the world have high waters and two low waters for each day, which last about 24 hours and 50 minutes. The difference in height between the high water and low water is called the range of tide, and it can be quite dramatic in narrower bays .Canada’s bays of Fundy , for example , commonly experiences the world’s most extreme tidal ranges , with daily differences of the 16 meters. Two other types of tides are influenced by the Sun, which is much farther away from the Earth and exerts less than half of the Moon’s gravitational force. When the Sun, the Moon and the Earth are directly in line, the solar and lunar gravitational forces add up to produce higher spring tides. The range of spring tides is intensified, with higher water marks and lower low water marks. However, when the Moon is in the first or third quarter, it is at a 90–degree angle with the Sun in relation to the Earth .The opposing solar and lunar forces partially cancel each other out, and the result is a lower tide. This is called a neap tide, which comes twice a month and has lower high water marks and higher low water marks. The range of neap tides is minimum. Some tides do not occur over water at all. The solid body of the Earth has slight elasticity, so lunar and solar gravity cause it to stretch very subtly. These changes in the Earth’s shape, although imperceptible to humans, are known as Earth tides. Another tidal phenomenon, atmospheric tides, is caused by the Sun’s heating of the Earth’s atmosphere. Like ordinary tides, they usually occur over 12–hour periods. Why does the author mention tsunamis in the passage?

Xem chi tiết 1 K lượt xem 6 năm trước

Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct word or phrase that best fits each of the number blanks from 31 to 35 A recent (31)_______ of a language learning magazine has consulted a number of experts in the field of second language acquisition. Their advice may prove invaluable for those considering a language course. One suggestion is that you access whether you are likely to be successful (32)_______ learning a language. Did you enjoy studying language at school, for example? Do you have enough time to learn a language ? The major cost will be your own time and effort. Therefore, you must make sure that course on offer leads to a recognized qualification. Also, be realistic in your (33)_______. If you don’t set achievable aims, you are more likely to give up. Don’t be deceived into thinking that the most expensive courses are the best. Shop around to get the best possible value for money. You should also bear in your mind that the quicker you learn a language, the more quickly you forget it. Sandra Miller, a French teacher, tried to teach herself German by enrolling on a crash course. Already fluent in four languages and with a sound knowledge of teaching methodology her chances of (34)_______ progress were high. Three years on she remembers very little. She feels her biggest mistake was not to follow up her first experience. "I think the teacher’s role is important. It's so nice to have somebody give you a/an (35)_______”. Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct word or phrase that best fits each of the number blanks from 31 to 35 A recent (31)_______ of a language learning magazine has consulted a number of experts in the field of second language acquisition. Their advice may prove invaluable for those considering a language course. One suggestion is that you access whether you are likely to be successful (32)_______ learning a language. Did you enjoy studying language at school, for example? Do you have enough time to learn a language ? The major cost will be your own time and effort. Therefore, you must make sure that course on offer leads to a recognized qualification. Also, be realistic in your (33)_______. If you don’t set achievable aims, you are more likely to give up. Don’t be deceived into thinking that the most expensive courses are the best. Shop around to get the best possible value for money. You should also bear in your mind that the quicker you learn a language, the more quickly you forget it. Sandra Miller, a French teacher, tried to teach herself German by enrolling on a crash course. Already fluent in four languages and with a sound knowledge of teaching methodology her chances of (34)_______ progress were high. Three years on she remembers very little. She feels her biggest mistake was not to follow up her first experience. "I think the teacher’s role is important. It's so nice to have somebody give you a/an (35)_______”.Điền vào ô số 35

Xem chi tiết 2.9 K lượt xem 6 năm trước

Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct word or phrase that best fits each of the number blanks from 31 to 35 A recent (31)_______ of a language learning magazine has consulted a number of experts in the field of second language acquisition. Their advice may prove invaluable for those considering a language course. One suggestion is that you access whether you are likely to be successful (32)_______ learning a language. Did you enjoy studying language at school, for example? Do you have enough time to learn a language ? The major cost will be your own time and effort. Therefore, you must make sure that course on offer leads to a recognized qualification. Also, be realistic in your (33)_______. If you don’t set achievable aims, you are more likely to give up. Don’t be deceived into thinking that the most expensive courses are the best. Shop around to get the best possible value for money. You should also bear in your mind that the quicker you learn a language, the more quickly you forget it. Sandra Miller, a French teacher, tried to teach herself German by enrolling on a crash course. Already fluent in four languages and with a sound knowledge of teaching methodology her chances of (34)_______ progress were high. Three years on she remembers very little. She feels her biggest mistake was not to follow up her first experience. "I think the teacher’s role is important. It's so nice to have somebody give you a/an (35)_______”. Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct word or phrase that best fits each of the number blanks from 31 to 35 A recent (31)_______ of a language learning magazine has consulted a number of experts in the field of second language acquisition. Their advice may prove invaluable for those considering a language course. One suggestion is that you access whether you are likely to be successful (32)_______ learning a language. Did you enjoy studying language at school, for example? Do you have enough time to learn a language ? The major cost will be your own time and effort. Therefore, you must make sure that course on offer leads to a recognized qualification. Also, be realistic in your (33)_______. If you don’t set achievable aims, you are more likely to give up. Don’t be deceived into thinking that the most expensive courses are the best. Shop around to get the best possible value for money. You should also bear in your mind that the quicker you learn a language, the more quickly you forget it. Sandra Miller, a French teacher, tried to teach herself German by enrolling on a crash course. Already fluent in four languages and with a sound knowledge of teaching methodology her chances of (34)_______ progress were high. Three years on she remembers very little. She feels her biggest mistake was not to follow up her first experience. "I think the teacher’s role is important. It's so nice to have somebody give you a/an (35)_______”.Điền vào ô số 34

Xem chi tiết 661 lượt xem 6 năm trước

Read the following passage and choose the correct answer to each of the questions. The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods. The second era was initiated in the early decades of the twentieth century and might be called "the vitamin period. " Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them. In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.Why did vitamin therapy begin losing favor in the 1950s?

Xem chi tiết 390 lượt xem 6 năm trước

Read the following passage and choose the correct answer to each of the questions. The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods. The second era was initiated in the early decades of the twentieth century and might be called "the vitamin period. " Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them. In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.The word “them” refers to _____.

Xem chi tiết 3.6 K lượt xem 6 năm trước

Read the following passage and choose the correct answer to each of the questions. The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods. The second era was initiated in the early decades of the twentieth century and might be called "the vitamin period. " Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them. In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.The word “reckless” is closest in meaning to _______.

Xem chi tiết 609 lượt xem 6 năm trước

Read the following passage and choose the correct answer to each of the questions. The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods. The second era was initiated in the early decades of the twentieth century and might be called "the vitamin period. " Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them. In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.It can be inferred from the passage that medical schools began to teach concepts of nutrition in order to _____.

Xem chi tiết 1.1 K lượt xem 6 năm trước

Read the following passage and choose the correct answer to each of the questions. The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods. The second era was initiated in the early decades of the twentieth century and might be called "the vitamin period. " Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them. In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.The word “tempting” is closet in meaning to _____.

Xem chi tiết 868 lượt xem 6 năm trước

Read the following passage and choose the correct answer to each of the questions. The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods. The second era was initiated in the early decades of the twentieth century and might be called "the vitamin period. " Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them. In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.It can be inferred from the passage that which of the following discoveries was made during the first era in the history of nutrition?

Xem chi tiết 1 K lượt xem 6 năm trước

 Read the following passage and choose the correct answer to each of the questions. The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods. The second era was initiated in the early decades of the twentieth century and might be called "the vitamin period. " Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them. In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems.What does the passage mainly discuss?

Xem chi tiết 783 lượt xem 6 năm trước