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【单选题】Organic FoodOrganic farming was among the fastest growing segments of U.S. agriculture during the 1990s. The value of retail. sales of organic food was estimated to be $16 billion in 2004. According t...
A.
As you can imagine, organic agricultural practices are quite distinct from those of "conventional" fanning.
B.
Organic farmers:
C.
feed soil and build soil matter with natural fertilizer to grow their crops use insect predators, mating disruption, traps and barriers to protect crops from pests and disease make use of crop rotation, mechanical tillage and hand-weeding, as well as cover crops, mulches, flame weeding and other management methods to control weed growth.As a last resort, organic farmers may apply certain botanical or other non-synthetic pesticides. Conventional farmers:,
D.
apply chemical fertilizers to the soil to grow their crops spray with insecticides to protect crops from pests and disease use synthetic herbicides to control weed growth.
E.
How Do I Know if a Food is Organic
F.
Look for the word "organic" on vegetables or pieces of fruit, or on the sign above the organic produce display. The word "organic" may also appear on packages of meat, cartons of milk or eggs, cheese and other single-ingredient foods. Foods labeled "100 percent organic" must contain only organic ingredients. Products containing at least 70 percent organic content can be labeled "made with organic ingredients". Those foods labeled simply "organic" must have at least 95 percent organic ingredients, by weight or fluid volume, excluding water and salt. Anyone who knowingly sells or labels a product "organic" that is not produced and handled in accordance with these regulations can face a civil penalty of up to $10,000.
G.
Foods grown and processed according to the federal standards will in most cases bear the seal "USDA Organic". As its use is voluntary, companies may choose not to display the seal.
H.
Why Should I Care if a Food is Organic According to the USDA, organic food production allows farmers to lower input costs, decrease reliance on nonrenewable resources, capture high-value markets and premium prices, and boost farm income. Organic agriculture also has many important environmental, benefits:
I.
It promotes sustainability by establishing an ecological balance to pr soil fertility or pest problems. In the long run, organic farms tend to conserve energy and protect the environment by maintaining ecological harmony.
J.
It enhances biodiversity, or the presence of multiple plant and animal species. Having a highly diverse genetic pool becomes useful in the future when beneficial characteristics can be tapped.
.
Because organic agriculture utilizes practices such as crop rotations, inter-cropping, symbiotic associations, cover crops and minimum tillage, the length of time that the soil is exposed to erosive forces is decreased, which minimizes nutrient losses and boosts soil productivity. By not using synthetic fertilizers and pesticides, organic agriculture-reduces pollution of groundwater.
K.
Organic agriculture helps to minimize the greenhouse effect and global warming through its ability to keep carbon in the soil.
L.
Why is Organic Food So Expensive
M.
Prices tend to be higher for organic titan conventional products. As stated on the Web site of the Food and Agriculture Organization (FAO) of the United Nations (UN), certified organic products are generally, more expensive than their conventional counterparts because:
N.
The organic food supply is limited as compared to demand. Production costs for organic foods are typically higher because of greater labor input and because farmers don’t produce enough of a single product to lower the overall cost.
.
Post-harvest handling of relatively small quantities of organic foods results in higher costs because organic and conventional 0roduce must be separated for processing and transportation.
.
Marketing and the distribution chain for organic products are relatively inefficient, and costs are higher because of relatively small volumes.
.
The FAO also notes that as the demand for organic food and products increases, technological innovations and economies of scale should reduce costs of production, processing, distribution and marketing for organic produce.
.
Is Organic Food Better than Conventional Food
.
Organic and conventional food must meet the same quality and safety standards. Organic food differs from conventionally produced food simply in the way it is grown, handled, and processed. There is no scientific evidence to suggest that it is more nutritious or safer than conventional food. A recently published report indicates that organic food is less likely to contain pesticide residues than conventional food. Yet, according to the National Research Council, the traces of pesticides left on conventionally grown products are unlikely to cause an increased cancer risk. Also, if fruits and vegetables are properly washed, most of the chemicals can be removed. As for taste, that’s up to you to decide what you like best. In general, people tend to find that the fresher a food is, the better it tastes, regardless of how it was produced.
相关题目：
【单选题】主要影响片剂中药物吸收的剂型因素不包括
A.
片剂的处方组成
B.
包装材料
C.
片剂的崩解、溶出和释放
D.
片剂制备工艺
E.
药物的pKa及脂溶性
【单选题】多菌灵对人畜毒性低，对植物安全，是一种高效（）的广谱杀菌剂。
A.
高毒
B.
低毒
C.
中毒
D.
无毒
【单选题】能够增加肾小管对磷的重吸收的是（）
A.
雌激素
B.
维生素D
C.
甲状旁腺素
D.
甲状腺素
E.
高血钙
【判断题】湿生植物宜在潮湿环境生长，不能长时间水分不足
A.
正确
B.
错误
【单选题】Organic FoodOrganic farming was among the fastest growing segments of U.S. agriculture during the 1990s. The value of retail. sales of organic food was estimated to be $16 billion in 2004. According t...
A.
As you can imagine, organic agricultural practices are quite distinct from those of "conventional" fanning.
B.
Organic farmers:
C.
feed soil and build soil matter with natural fertilizer to grow their crops use insect predators, mating disruption, traps and barriers to protect crops from pests and disease make use of crop rotation, mechanical tillage and hand-weeding, as well as cover crops, mulches, flame weeding and other management methods to control weed growth.As a last resort, organic farmers may apply certain botanical or other non-synthetic pesticides. Conventional farmers:,
D.
apply chemical fertilizers to the soil to grow their crops spray with insecticides to protect crops from pests and disease use synthetic herbicides to control weed growth.
E.
How Do I Know if a Food is Organic
F.
Look for the word "organic" on vegetables or pieces of fruit, or on the sign above the organic produce display. The word "organic" may also appear on packages of meat, cartons of milk or eggs, cheese and other single-ingredient foods. Foods labeled "100 percent organic" must contain only organic ingredients. Products containing at least 70 percent organic content can be labeled "made with organic ingredients". Those foods labeled simply "organic" must have at least 95 percent organic ingredients, by weight or fluid volume, excluding water and salt. Anyone who knowingly sells or labels a product "organic" that is not produced and handled in accordance with these regulations can face a civil penalty of up to $10,000.
G.
Foods grown and processed according to the federal standards will in most cases bear the seal "USDA Organic". As its use is voluntary, companies may choose not to display the seal.
H.
Why Should I Care if a Food is Organic According to the USDA, organic food production allows farmers to lower input costs, decrease reliance on nonrenewable resources, capture high-value markets and premium prices, and boost farm income. Organic agriculture also has many important environmental, benefits:
I.
It promotes sustainability by establishing an ecological balance to pr soil fertility or pest problems. In the long run, organic farms tend to conserve energy and protect the environment by maintaining ecological harmony.
J.
It enhances biodiversity, or the presence of multiple plant and animal species. Having a highly diverse genetic pool becomes useful in the future when beneficial characteristics can be tapped.
.
Because organic agriculture utilizes practices such as crop rotations, inter-cropping, symbiotic associations, cover crops and minimum tillage, the length of time that the soil is exposed to erosive forces is decreased, which minimizes nutrient losses and boosts soil productivity. By not using synthetic fertilizers and pesticides, organic agriculture-reduces pollution of groundwater.
K.
Organic agriculture helps to minimize the greenhouse effect and global warming through its ability to keep carbon in the soil.
L.
Why is Organic Food So Expensive
M.
Prices tend to be higher for organic titan conventional products. As stated on the Web site of the Food and Agriculture Organization (FAO) of the United Nations (UN), certified organic products are generally, more expensive than their conventional counterparts because:
N.
The organic food supply is limited as compared to demand. Production costs for organic foods are typically higher because of greater labor input and because farmers don’t produce enough of a single product to lower the overall cost.
.
Post-harvest handling of relatively small quantities of organic foods results in higher costs because organic and conventional 0roduce must be separated for processing and transportation.
.
Marketing and the distribution chain for organic products are relatively inefficient, and costs are higher because of relatively small volumes.
.
The FAO also notes that as the demand for organic food and products increases, technological innovations and economies of scale should reduce costs of production, processing, distribution and marketing for organic produce.
.
Is Organic Food Better than Conventional Food
.
Organic and conventional food must meet the same quality and safety standards. Organic food differs from conventionally produced food simply in the way it is grown, handled, and processed. There is no scientific evidence to suggest that it is more nutritious or safer than conventional food. A recently published report indicates that organic food is less likely to contain pesticide residues than conventional food. Yet, according to the National Research Council, the traces of pesticides left on conventionally grown products are unlikely to cause an increased cancer risk. Also, if fruits and vegetables are properly washed, most of the chemicals can be removed. As for taste, that’s up to you to decide what you like best. In general, people tend to find that the fresher a food is, the better it tastes, regardless of how it was produced.
【单选题】下列选项中植物姿态不同的一组是（）。
A.
香樟、广玉兰、鹅掌楸
B.
栾树、黄连木、金枝干头柏
C.
蜡梅、紫荆、金钟花
D.
中华绣线菊、云南黄馨、粉花绣线菊
【单选题】磷酸盐包埋材料属于
A.
低熔合金铸造包埋材料
B.
中熔合金铸造包埋材料
C.
高熔合金铸造包埋材料
D.
铸钛包埋材料 E．以上均不是
【单选题】磷酸盐结合剂包埋料的凝固膨胀约为（）。
A.
0-1％～0.2％
B.
0.6％
C.
0.8％～1.0％
D.
1.6％
E.
2％
【单选题】请选出1种观果植物( )。
A.
佛手
B.
油茶花
C.
高山榕
D.
假槟榔
【单选题】下列特征中，为大戟科植物普遍具有的是()。
A.
对生、边脉
B.
乳汁、腺体
C.
边脉、托叶环痕
D.
透明油点、芳香气味
【多选题】高等植物的无氧呼吸可以产生（）
A.
酒精
B.
苹果酸
C.
乳酸
【判断题】单食性昆虫只取食一种植物或动物。
A.
正确
B.
错误
【判断题】 地面吸收太阳短波辐射，升温，放射长波辐射。（ ）
A.
正确
B.
错误