2 Bacteria

What are Bacteria? (part 2)

Before-reading task

Task 1. Before reading the text practice the following words. Translate them

outnumber [ˌaut'nʌmbə] offspring ['ɔfsprɪŋ] scraping ['skreɪpɪŋ] diarrhea [ˌdaɪə'rɪə]

archaea [ɑːˈkiːə] animalcule [ˌænɪ'mælkjuːl] scratch [skræʧ] subsist [səb'sɪst]

dwell [dwel] compelling [kəm'pelɪŋ] whip [(h)wɪp] lethal ['liːθ(ə)l]

20 Things You Didn't Know About... Bacteria The oldest life on the planet still has a few secrets 1.At about 5 million trillion trillion strong, bacteria and their cousins, the archaea, vastly outnumber all other life-forms on earth. 2.Lined up end to end, they would stretch some 10 billion light-years—literally from here to the edge of the visible universe. 3.And there are always more on the way. Pseudomonas natriegens, an ocean-dwelling bacterium, can go from birth to reproduction in 10 minutes flat. In five hours a single cell could theoretically give rise to more than 1 billion offspring. 4.  Bacteria have been around for at least 3.5 billion years, making them the oldest known life-form on the planet. 5.  Humans didn’t catch a glimpse of them, though, until 1674, when Dutch scientist Antonie van Leeuwenhoek spotted tiny swimming “animacules” while fiddling with the newly invented microscope. 6.  A compelling argument for brushing: He discovered them while examining pond water and scrapings from the human mouth. 7.  Most bacteria have yet to be identified. In 2003 geneticist J. Craig Venter began trolling the high seas and analyzing the water. On his first trip he fished out more than a million never-before-seen bacterial genes. 8.  The first artificial life-form will be not a robot but a bacterium. Not content with finding natural bacteria, Venter is leading an effort to build a bacterium from scratch. 9.  No escaping them: Your body has 10 times more bacterial cells than human cells. 10.  Can’t catch them, either. Whipping their tails, E. coli can travel 25 times their own length in 1 second, equivalent to a horse running 135 miles per hour. 11.  Bacteria have even set up permanent camp inside our cells. Mitochondria, the power­houses that supply energy to nearly every cell in the body, are the descendants of bacteria that were engulfed by larger microorganisms billions of years ago. 12.  When you pop a pill to kill off a bad bug, you kill some of the good guys, too. A bacterium called Clostridium difficile can move into the prime intestinal real estate cleared out by antibiotics, causing painful inflammation and diarrhea. 13.  Bacteria are adept at developing resistance to antibiotics. Among the deadliest of resistant bacteria is MRSA, which killed 19,000 Americans in 2005 alone. 14.  MRSA’s deadliness comes in part from a class of chemicals known as carotenoids, which MRSA uses to fight off our immune systems. Ironically, carotenoids are found in many healthy fruits and vegetables and may reduce cancer risk. 15.  But most bacteria are harmless, and some are even helpful in aiding our digestion. Mice with bacteria-free intestines need to eat 41 percent more calories than their germy counterparts. 16.  Floating bacteria are extremely effective at spurring condensation, leading to snow and rain. Some scientists propose spraying bacteria into the clouds to end droughts. 17.  Certain bacteria thrive in extreme conditions. In 2006 a probe at a South African gold mine turned up bacteria living nearly two miles underground, subsisting on the energy given off by radioactive rocks. 18.  Another species, Deinococcus radiodurans, can survive almost 10,000 times the dose of radiation lethal to humans, making it a prime candidate for the cleanup of nuclear waste. 19.  The Midas touch: Australian scientists found that a bacterium called Ralstonia metallidurans can turn dissolved gold into solid nuggets. 20.  But can they run Windows? By programming instructions into their genes, scientists have engineered E. coli that act like computers, assembling into glowing bull’s-eye shapes on command.

Task 2. Find English equivalents in the text:

1. превосходить по численности все другие формы жизни на земле

2. выстроены из конца в конец

3. край видимой вселенной

4. обитающая в океане бактерия

5. от рождения до размножения за 10 минут

6. пятнистые крошечные плавучие «животные»

7. соскобы из человеческого рта

8. более миллиона неизвестных ранее бактериальных генов

9. веский аргумент в пользу чистки

10. охвачены более крупными микроорганизмами

11. мыши с кишечником без бактерий

12. смертельная доза облучения для человека

Task 3. Fill in the chart with the names of some bacteria and their effect on a human

organism:

Bacterium	Its effect

Bacteria cell structure Did you know? Task 4. Read the text and do the tasks Interesting Bacteria Facts:

Tiny, one-celled creatures, bacteria have been around for millions of years, even longer than humans. They get nutrients directly from their environment in order to live. Some bacteria humans need in order to get nutrients into the body; these normally live in the intestine. Other bacteria reproduce inside the body and cause different infections - sore throats, ear infections, cavities, and pneumonia, among others. Other bacteria are used in labs to make things like medicine and vaccines. Read on for more fun and interesting facts about bacteria! Bacteria are alive! They are the simplest form of life known, being made up of only one cell. They occur everywhere - bread, yogurt, dirt, and inside of humans!

Bacteria occur in all different shapes and sizes - ball shaped called spheres, rod-shaped, and spiral shaped.

Some bacteria live on the inside of animals like cows. These bacteria allow cows (and other animals that eat grass) to digest the material the grass is made of, called cellulose. Humans don't have the right bacteria, and so we can't eat grass!

Bacteria that enter human bodies that don't belong there invade human cells, stealing nutrients and releasing poisons. These bacteria can make people sick, can cause skin infections, and are generally very bad for people.

There are medications that can kill bacteria, which are called antibiotics. Most sickness (sore throats, runny nose, upset stomach) are caused by viruses, which antibiotics won't do anything against. If the doctor decides an illness is caused by bacteria, antibiotics can make the illness shorter, and not as bad.

The absolute best way to protect against getting sick with bacteria is washing hands, especially after using the restroom.

Bacteria can even live in food. Properly cooking food is a great way to kill off any bacteria that can live in it. Eating food that isn't cooked well enough can make people really sick.

How can doctors figure out what bacteria are infecting someone? They take different samples of blood, urine, and other fluids, make whatever is in it grow, and look at it under a microscope. They can even test different antibiotics to see which medicines can kill the bacteria!

Some bacteria can hide from the immune system, and others can even survive the immune system trying to destroy them. These types of bacteria can only be killed by medications, and sometimes even surgery.

Bacteria can also cause infections in the skin. Sometimes, if the infection is close to the surface, a doctor can give an antibiotic in an ointment that goes on the skin. Other skin infections are serious enough that an antibiotic that is swallowed has to be taken.

A good way to prevent spreading bacteria to others is to cover the mouth and nose when coughing and sneezing. Using a Kleenex is also a good idea, but must be thrown away after use. Make sure to wash hands after coughing or sneezing as well.

Supplements like zinc and vitamin C support the immune system and can help fight infection.

Task 5. Answer the questions:

1. Why can’t humans eat and digest grass like cows?

2. How do we call medications that can kill bacteria?

3. How can doctors figure out what bacteria are infecting someone?

4. How do some bacteria influence the immune system?

5. What is a good way to prevent spreading bacteria to others?

6. What supplements can support the immune system and can help fight infection?