7.7 细菌和人类
Section outline
-
Can you guess what organisms are pictured here?
::你能猜到这里有什么样的生物吗?Here’s a clue: There are more organisms like these than any other on Earth. Here’s another clue: Each organism consists of a single without a .
::还有一个线索:每个生物都由一个没有生物的单一组成。The organisms are called Salmonella . If the word Salmonella rings a bell, that’s probably because Salmonella causes human diseases such as food poisoning. Many other types of bacteria also cause human diseases. But not all bacteria are harmful to people. In fact, we could not survive without many of the trillions of bacteria that live in or on the .
::沙门氏菌被称作“沙门氏菌 ” 。 如果“沙门氏菌”这个词敲响了一个钟,那可能是因为沙门氏菌引起人类疾病,比如食物中毒。许多其他类型的细菌也造成人类疾病。 但并非所有细菌都对人有害。 事实上,如果没有许多数万亿种细菌,我们无法生存下去。Bacteria and Humans
::细菌和人类Bacteria and humans have many important relationships. Bacteria make our lives easier in a number of ways. In fact, we could not survive without them. On the other hand, bacteria can also make us sick.
::细菌和人类有许多重要的关系。细菌让我们的生活在很多方面更加轻松。事实上,没有细菌,我们就无法生存。另一方面,细菌也会让我们生病。Benefits of Bacteria
::细菌(细菌)和细菌(细菌)Bacteria provide vital services. They are important decomposers . They are also needed for the carbon and nitrogen cycles. There are billions of bacteria inside the human intestines. They help digest food, make vitamins , and play other important roles. Humans also use bacteria in many other ways, including:
::细菌提供重要的服务。它们是重要的分解器。 碳和氮循环也需要它们。 人类肠内有数十亿细菌。 它们帮助消化食物,制造维生素,并发挥其他重要作用。 人类还以许多其他方式使用细菌, 包括:-
Creating products, such as ethanol and
.
::创造产品,如乙醇和乙醇。 -
Making
drugs
, such as
antibiotics
and
vaccines
.
::制造药物,如抗生素和疫苗。 -
Making biogas, such as methane.
::制造沼气,如甲烷。 -
Cleaning up oil spills and toxic wastes.
::清理漏油和有毒废物。 -
Killing plant pests.
::杀害植物害虫。 -
Transferring normal
genes
to human cells in
.
::将正常基因转移到人体细胞 -
Fermenting foods (see
Figure
).
::发酵食品(见图)。
Fermented Foods. Fermentation is a type of respiration that doesn’t use oxygen. Fermentation by bacteria is used in brewing and baking. It is also used to make the foods pictured here. Bacteria and Disease
::细菌及疾病及疾病You have ten times as many bacteria as human cells in your body. Most of these bacteria are harmless. However, bacteria can also cause disease. Examples of include tetanus, syphilis , and food poisoning. Bacteria may spread directly from one person to another. For example, they can spread through touching, coughing, or sneezing. They may also spread via food, , or objects.
::你体内的细菌数量是人体细胞的十倍。这些细菌大多是无害的。然而,细菌也可能造成疾病。例如破伤风、梅毒和食物中毒。细菌可能直接从一个人扩散到另一个人。例如,它们可以通过触摸、咳嗽或喷嚏传播,也可以通过食物、食物或物品传播。Another way bacteria and other can spread is by vectors . A vector is an organism that spreads pathogens from host to host. are the most common vectors of human diseases. Figure shows two examples.
::细菌和其他病原体也可以通过病媒传播。病媒是一种将病原体从宿主传播到宿主的有机体。它是人类疾病最常见的病原体。图中举了两个例子。Bacterial Disease Vectors. A) Ticks spread bacteria that cause Lyme disease. B) Deerflies spread bacteria that cause tularemia. Humans have literally walked into some new bacterial diseases. When people come into contact with wild , they may become part of natural cycles of disease transmission. Consider Lyme disease. It’s caused by bacteria that normally infect small, wild mammals , such as mice. A tick bites a mouse and picks up the bacteria. The tick may then bite a human who invades the natural habitat . Through the bite, the bacteria are transmitted to the human host.
::人类实际上已经进入了一些新的细菌疾病。当人们接触野生疾病时,它们可能成为疾病传播的自然循环的一部分。看看莱姆病。它是由细菌造成的,细菌通常感染小的野生哺乳动物,如小鼠。一滴虫咬老鼠,抓起细菌。当它咬到一个侵入自然栖息地的人时,它可能会咬到。通过咬,细菌会传染给人类宿主。Controlling Bacteria
::控制细菌Bacteria in food or water usually can be killed by heating it to a high temperature (generally, at least 74°C, or 165°F). Bacteria on many surfaces can be killed with chlorine bleach or other disinfectants. Bacterial infections in people can be treated with antibiotic drugs . For example, if you ever had “strep” throat, you were probably treated with an antibiotic.
::食物或水中的细菌通常可以通过加热到高温(通常至少74°C或165°F)来杀死。 许多表面的细菌可能用氯漂白剂或其他消毒剂来杀死。 人们的细菌感染可以用抗生素药物来治疗。 比如,如果你的喉咙有“刺塞 ” , 你可能会被抗生素治疗。Antibiotics have saved many lives. However, misuse and over-use of the drugs have led to antibiotic resistance in bacteria. Figure shows how antibiotic resistance evolves. Some strains of bacteria are now resistant to most common antibiotics. These infections are very difficult to treat.
::抗生素挽救了许多生命,但滥用和过度使用药物导致细菌对抗生素的抗药性,图显示抗生素抗药性是如何演变的,一些细菌菌株现在对最常见的抗生素具有抗药性,这些感染非常难以治疗。Evolution of Antibiotic Resistance in Bacteria. This diagram shows how antibiotic resistance evolves by natural selection. Science Friday : Your Very Special Bacterial Cloud
::科学星期五:你的特别细菌云There is a cloud surrounding you, formed by billions of bacteria that slough off your body with every movement you make. In this video by Science Friday , researchers at the University of Oregon, revealed that they can detect and catalog this unique personal microbial cloud.
::围绕你的云层是由数十亿细菌形成的,这些细菌以你的每一动作将你的身体从身体上抹去。在科学周五的这段视频中,俄勒冈大学的研究人员透露,他们可以检测到这种独特的个人微生物云,并将其编成目录。Science Friday : Subvisual Subway: The Art of New York City's Bacterial World
::科学 星期五: 亚可视地铁:纽约市细菌世界的艺术An urban legend states that "using the handrails on the subway is like shaking hands with 100 people." In this video by Science Friday , Craig Ward sampled the bacteria on subway lines around New York City to create striking and unconventional "portraits" of NYC commuters.
::一位城市传奇人物指出,“在地铁上使用扶手就像与100人握手一样。 ”在这个由科学星期五拍摄的视频中,克雷格·沃德在纽约市周围的地铁线上采样了细菌,制造了纽约市通勤者的惊人和非常规的“肖像 ” 。Summary
::摘要-
Bacteria and humans have many important relationships. Bacteria provide humans with a number of services. They also cause human diseases.
::细菌和人类有许多重要的关系。细菌为人类提供多种服务,它们也造成人类疾病。
Review
::回顾-
How can bacteria cause disease?
::细菌怎么会造成疾病? -
List three benefits of bacteria.
::列举细菌的三种好处。 -
How can bacteria be killed?
::细菌如何被杀死?
-
Creating products, such as ethanol and
.
