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Populations tend to grow at an exponential rate. This means that they progressivel, double. As an example of this type of growth rate, take one penny and double it every day for one month. After the first week, you would have only 64 cents, but after the fourth week you would have over a million dollars.
This helps explain why the population has come on "all of a sudden". It took from the beginning of human life to the year 1830 for the population of the earth to reach one billion. That represents a time span of at least two million years. Then it took from 1830 to 1930 for world population to reach 2 billion. The next billion was added by 1960, only thirty years, and in 1975 world population reached 4 billion, which is another billion people in only Fifteen years.
World population is increasing at a rate of 9,000 per hour, 220,000 per day, 80 million per year. This is not only due to higher birth rates, but to lower death rates as well. The number of births has not declined at the same rate as the number of deaths.
Some countries, such as Columbia, Thailand, Morocco, Costa Rica, and the Philippines, are doubling their populations about every twenty - one years, with a growth rate of 3.3 percent a year or more. The United States is doubling its population about every eighty-seven years, with a rate of 0.8 percent per year. Every time a population doubles, the country involved needs twice as much of everything, including hospitals, schools, resources, food and medicines to care for its people. It is easy to see that this is very difficult to achieve for the more rapidly growing countries.

A:the growth of world population B:one type of the exponential rate C:the population problem of more rapidly growing countries D:the possible ways of dealing with the rapid population growth

Biotechnology Biotechnology in one form or another has flourished since prehistoric times. When the first human beings realized that they could plant their own crops and breed their own animals, they learned to use biotechnology. The discovery that fruit juices fermented(发酵) in wine, or that milk could be converted into cheese or yogurt(酸乳酶) or that beer could be made by fermenting solutions of malt(麦芽) and hops(啤酒花) began the study of biotechnology. When the first bakers found that they could make a soft, spongy(多乳的) bread rather than a firm, thin cracker they we’’re acting as fledgling(缺乏经验的) biotechnologists. The first animal breeders, realizing that different physical traits could be either magnified or lost by mating appropriate pairs of animals, engaged in the manipulations of biotechnology. What then is biotechnology? The term brings to mind different things. Some think of developing new types of animals. Others dream of almost unlimited sources of human therapeutic (治疗的) drugs. Still others envision (想象) the possibility of growing crops that are more nutritious(有养分的) and naturally pest-resistant (有抵抗力的) to feed a rapidly growing world population. This question elicits (引发) almost as many first-thought responses as there are people to whom the question can be posed. In its purest form, the term "biotechnology" refers to the use of living organisms or their products to modify human health and the human environment. Prehistoric biotechnologists did this as they used yeast cells to raise bread dough(生面团) and to ferment alcoholic beverages, and bacterial cells to make cheeses and yogurts and as they bred their strong, productive animals to make even stronger and more productive offspring. Throughout human history, we have learned a great deal about the different organisms that our ancestors used so effectively. The marked increase in our understanding of these organisms and their cell products gains us the ability to control the many functions of various cells and organisms. Using the techniques of gene splicing(叠接) and recombine DNA technology, we can now actually combine the genetic elements of two or more living cells. Functioning lengths of DNA can be taken from one organism and placed into the cells of another organism. As a result, for example, we can cause bacterial cells to produce human molecules cows can produce more milk or the same amount of feed, and we can synthesize the rapeutic molecules that have never before existed. The term" biotechnology" may bring different things to mind except______.

A:new types of animals B:crops that are more nutritious and naturally pest-resistant C:stronger and more productive offspring of animals D:rapidly growing world population

Biotechnology Biotechnology in one form or another has flourished since prehistoric times. When the first human beings realized that they could plant their own crops and breed their own animals, they learned to use biotechnology. The discovery that fruit juices fermented(发酵) in wine, or that milk could be converted into cheese or yogurt(酸乳酶) or that beer could be made by fermenting solutions of malt(麦芽) and hops(啤酒花) began the study of biotechnology. When the first bakers found that they could make a soft, spongy(多乳的) bread rather than a firm, thin cracker they we’’re acting as fledgling(缺乏经验的) biotechnologists. The first animal breeders, realizing that different physical traits could be either magnified or lost by mating appropriate pairs of animals, engaged in the manipulations of biotechnology. What then is biotechnology? The term brings to mind different things. Some think of developing new types of animals. Others dream of almost unlimited sources of human therapeutic (治疗的) drugs. Still others envision (想象) the possibility of growing crops that are more nutritious(有养分的) and naturally pest-resistant (有抵抗力的) to feed a rapidly growing world population. This question elicits (引发) almost as many first-thought responses as there are people to whom the question can be posed. In its purest form, the term "biotechnology" refers to the use of living organisms or their products to modify human health and the human environment. Prehistoric biotechnologists did this as they used yeast cells to raise bread dough(生面团) and to ferment alcoholic beverages, and bacterial cells to make cheeses and yogurts and as they bred their strong, productive animals to make even stronger and more productive offspring. Throughout human history, we have learned a great deal about the different organisms that our ancestors used so effectively. The marked increase in our understanding of these organisms and their cell products gains us the ability to control the many functions of various cells and organisms. Using the techniques of gene splicing(叠接) and recombine DNA technology, we can now actually combine the genetic elements of two or more living cells. Functioning lengths of DNA can be taken from one organism and placed into the cells of another organism. As a result, for example, we can cause bacterial cells to produce human molecules cows can produce more milk or the same amount of feed, and we can synthesize the rapeutic molecules that have never before existed. The term" biotechnology" may bring different things to mind except______.

A:new types of animals B:crops that are more nutritious and naturally pest-resistant C:stronger and more productive offspring of animals D:rapidly growing world population

Biotechnology Biotechnology in one form or another has flourished since prehistoric times. When the first human beings realized that they could plant their own crops and breed their own animals, they learned to use biotechnology. The discovery that fruit juices fermented(发酵) in wine, or that milk could be converted into cheese or yogurt(酸乳酶) or that beer could be made by fermenting solutions of malt(麦芽) and hops(啤酒花) began the study of biotechnology. When the first bakers found that they could make a soft, spongy(多乳的) bread rather than a firm, thin cracker they we’’re acting as fledgling(缺乏经验的) biotechnologists. The first animal breeders, realizing that different physical traits could be either magnified or lost by mating appropriate pairs of animals, engaged in the manipulations of biotechnology. What then is biotechnology? The term brings to mind different things. Some think of developing new types of animals. Others dream of almost unlimited sources of human therapeutic (治疗的) drugs. Still others envision (想象) the possibility of growing crops that are more nutritious(有养分的) and naturally pest-resistant (有抵抗力的) to feed a rapidly growing world population. This question elicits (引发) almost as many first-thought responses as there are people to whom the question can be posed. In its purest form, the term "biotechnology" refers to the use of living organisms or their products to modify human health and the human environment. Prehistoric biotechnologists did this as they used yeast cells to raise bread dough(生面团) and to ferment alcoholic beverages, and bacterial cells to make cheeses and yogurts and as they bred their strong, productive animals to make even stronger and more productive offspring. Throughout human history, we have learned a great deal about the different organisms that our ancestors used so effectively. The marked increase in our understanding of these organisms and their cell products gains us the ability to control the many functions of various cells and organisms. Using the techniques of gene splicing(叠接) and recombine DNA technology, we can now actually combine the genetic elements of two or more living cells. Functioning lengths of DNA can be taken from one organism and placed into the cells of another organism. As a result, for example, we can cause bacterial cells to produce human molecules cows can produce more milk or the same amount of feed, and we can synthesize the rapeutic molecules that have never before existed. The term" biotechnology" may bring different things to mind except______.

A:new types of animals B:crops that are more nutritious and naturally pest-resistant C:stronger and more productive offspring of animals D:rapidly growing world population

Biotechnology Biotechnology in one form or another has flourished since prehistoric times. When the first human beings realized that they could plant their own crops and breed their own animals, they learned to use biotechnology. The discovery that fruit juices fermented(发酵) in wine, or that milk could be converted into cheese or yogurt(酸乳酶) or that beer could be made by fermenting solutions of malt(麦芽) and hops(啤酒花) began the study of biotechnology. When the first bakers found that they could make a soft, spongy(多乳的) bread rather than a firm, thin cracker they we’’re acting as fledgling(缺乏经验的) biotechnologists. The first animal breeders, realizing that different physical traits could be either magnified or lost by mating appropriate pairs of animals, engaged in the manipulations of biotechnology. What then is biotechnology? The term brings to mind different things. Some think of developing new types of animals. Others dream of almost unlimited sources of human therapeutic (治疗的) drugs. Still others envision (想象) the possibility of growing crops that are more nutritious(有养分的) and naturally pest-resistant (有抵抗力的) to feed a rapidly growing world population. This question elicits (引发) almost as many first-thought responses as there are people to whom the question can be posed. In its purest form, the term "biotechnology" refers to the use of living organisms or their products to modify human health and the human environment. Prehistoric biotechnologists did this as they used yeast cells to raise bread dough(生面团) and to ferment alcoholic beverages, and bacterial cells to make cheeses and yogurts and as they bred their strong, productive animals to make even stronger and more productive offspring. Throughout human history, we have learned a great deal about the different organisms that our ancestors used so effectively. The marked increase in our understanding of these organisms and their cell products gains us the ability to control the many functions of various cells and organisms. Using the techniques of gene splicing(叠接) and recombine DNA technology, we can now actually combine the genetic elements of two or more living cells. Functioning lengths of DNA can be taken from one organism and placed into the cells of another organism. As a result, for example, we can cause bacterial cells to produce human molecules cows can produce more milk or the same amount of feed, and we can synthesize the rapeutic molecules that have never before existed. The term" biotechnology" may bring different things to mind except______.

A:new types of animals B:crops that are more nutritious and naturally pest-resistant C:stronger and more productive offspring of animals D:rapidly growing world population

Biotechnology Biotechnology in one form or another has flourished since prehistoric times. When the first human beings realized that they could plant their own crops and breed their own animals, they learned to use biotechnology. The discovery that fruit juices fermented(发酵) in wine, or that milk could be converted into cheese or yogurt(酸乳酶) or that beer could be made by fermenting solutions of malt(麦芽) and hops(啤酒花) began the study of biotechnology. When the first bakers found that they could make a soft, spongy(多乳的) bread rather than a firm, thin cracker they we’’re acting as fledgling(缺乏经验的) biotechnologists. The first animal breeders, realizing that different physical traits could be either magnified or lost by mating appropriate pairs of animals, engaged in the manipulations of biotechnology. What then is biotechnology? The term brings to mind different things. Some think of developing new types of animals. Others dream of almost unlimited sources of human therapeutic (治疗的) drugs. Still others envision (想象) the possibility of growing crops that are more nutritious(有养分的) and naturally pest-resistant (有抵抗力的) to feed a rapidly growing world population. This question elicits (引发) almost as many first-thought responses as there are people to whom the question can be posed. In its purest form, the term "biotechnology" refers to the use of living organisms or their products to modify human health and the human environment. Prehistoric biotechnologists did this as they used yeast cells to raise bread dough(生面团) and to ferment alcoholic beverages, and bacterial cells to make cheeses and yogurts and as they bred their strong, productive animals to make even stronger and more productive offspring. Throughout human history, we have learned a great deal about the different organisms that our ancestors used so effectively. The marked increase in our understanding of these organisms and their cell products gains us the ability to control the many functions of various cells and organisms. Using the techniques of gene splicing(叠接) and recombine DNA technology, we can now actually combine the genetic elements of two or more living cells. Functioning lengths of DNA can be taken from one organism and placed into the cells of another organism. As a result, for example, we can cause bacterial cells to produce human molecules cows can produce more milk or the same amount of feed, and we can synthesize the rapeutic molecules that have never before existed. The term" biotechnology" may bring different things to mind except______.

A:new types of animals B:crops that are more nutritious and naturally pest-resistant C:stronger and more productive offspring of animals D:rapidly growing world population