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Shark Facts There are almost 400 different kinds of sharks. Each kind of shark looks different, has a unique diet, and behaves differently. There are sharks in all four oceans of the world. Some sharks are longer than a school bus, while others are so small they can live in fish tanks. Sharks come in all kinds of colors. Most of the time, their skin color helps them blend in with their surroundings. But, some’sharks that live in the deepest part of the ocean actually have parts that glow in the dark. Most sharks live in salt water, but some can live in fresh water. All sharks are unique, or have different qualities that make them so special. Sharks are actually a type of fish. There are some similarities as well as differences between sharks and typical fish. Shark skeletons are made of cartilage. Fish skeletons are made of bones. Cartilage is the bendy, tough substance in people’s ears and noses. Like other fish, sharks have gills. Gills are how fish breathe. Unlike fish, people use lungs to get oxygen from the air. Fish get oxygen from the water using gills. Water needs to move over the gills so that sharks and fish get enough oxygen. To keep the water moving, most sharks need to swim in water that has a very strong current. Sharks have lots of teeth that are arranged in many rows, rather than in just one row like people. The teeth from the outside row gradually fall out, and teeth from the next row take their place. Some sharks will lose 30,000 teeth in a lifetime! Each species of shark has different kinds of teeth. This is because different sharks eat different kinds of food. Some sharks eat food as small as plankton(浮游生物) while other sharks eat animals as big as sea turtles. Most sharks do not eat very often. Some sharks will go weeks between meals. Sharks are at the top of the ocean food chain, which means that no animal is hunting them for food. This position is very important because sharks keep the other animal populations from growing out of control. This process helps ensure there is diversity, or many types, of life in the oceans. Sharks have many teeth arranged in rows.
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Tech Addiction" Harms Learning" The study of 267 pupils aged 11 to 18 -Techno Addicts: Young Person Addiction to Technology-was carried out by researchers at Cranfield School of Management. Northampton Business School and academic consultancy AJM Associates. Researchers used a written questionnaire to examine the nature and the volume of mobile phone calls and text messaging as well as computer use including e - mail, instant messaging and accessing social networking sites. They found 62% first used or owned a computer before the age of eight, 80% first used the internet between the ages of five and 10,58% first used a mobile Phone between the ages of eight and 10 and 58% have had access to a social networking sites between the ages of eleven and 13. Over 63% felt addicted to the internet. Over 30% reported spending between one or two hours a day using the internet and 26% said they spent up to six or more hours a day. On average, pupils said they spent between one and two hours on social networking sites each day. Over one in five(20.2% )said they left the phone on in lessons—which is usually forbidden by schools. Over a third (39%) admitted that text shortcuts damaged the quality of their written English, particularly when it came to spelling. And 84% openly admitted copying chunks of information from the internet into their homework or projects on a number of occasions. Poor attention levels Dr Nada Kakabadse from Northampton Business School said modern technology, such as mobile phones and handheld computer games, was having an impact on pupils’ attention levels. "They are hiding these things under the desks so their concentration cannot be equally divided, they ore not focusing on what’s going on in class." Dr Kakabadse said pupils were also getting into a bad habit of plagiarism. "For their homework, instead of reading the book, they go on the internet and lift it. " She also raised concerns about the text - messaging abbreviations to which young people had grown accustomed. "They have invented a new language. This kind of abbreviation they unconsciously bring into their assignments. " "So they will have difficulty communicating with others and making themselves understood. Of course, language should evolve but maybe not so quickly. \ How many pupils are addicted to the internet according to the study
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if you were to begin a new job tomorrow, you would bring with you some basic strengths and weaknesses. Success or (51) in your work would depend, to some great extent, (52) your ability to use your strengths and weaknesses to the best advantage. Of the utmost importance is your attitude. A person (53) begins a job convinced that he isn’t going to like it or is (54) that he is going to show a weakness which can only harm his Success. On the other hand, a person who is firm in his belief that he is probably as capable (55) doing the work as anyone else and who is willing to make a cheerful attempt at it possesses a certain strength of purpose. The chances are that he will do well. (56) the required skills for a particular job is strength. Lacking those skills is obviously a weakness. A bookkeeper who can’t add or a carpenter who can’t cut a straight line with a saw (57) hopeless eases. This book has been designed to help you capitalize (58) the strength and overcome the (59) that you bring to the job of learning. But in groups to measure your development, you must first (60) stock of somewhere you stand now. As we get further along in the book, we’ll be (61) in some detail with specific processes for developing and strengthening (62) skills. However (63) begin with, you should stop (64) examine your present strengths and weaknesses in three alreas that are critical to your success or failure in school: your (65) , your reading and communication skills, and your study habits.
Taking Showers" Can Make You III" Showering may be bad for your health, say US scientists, who have shown that dirty shower heads can deliver a face full of harmful bacteria. Tests revealed nearly a third of devices harbour significant levels of Mycobacterium avium, a bug that causes lung disease. Levels of M. avium were 100 times higher in shower head than those found in typical household water supplies. M. avium forms a biofilm that clings to the inside of the shower head, repofls the National Academy of Science. In the Proceedings journal, the study authors say their findings might explain why there have been more cases of these lung infections in recent years, linked with people tending to take more showers and fewer baths. When the researchers swabbed and tested 50 shower heads from nine cities in seven different states in the US, including New York City and Denver, they found 30% of the devices posed a potential risk. Lead researcher Professor Norman Pace, said:" If you are getting a face full of water when you first turn your shower on, that means you are probably getting a particularly high load of Mycobacterium avium, which may not be too healthy. " While it is rarely a problem for most healthy people, those with weakened immune systems, like the elderly, pregnant women or those who are fighting off other diseases, can be susceptible to infection. Water spurting from shower heads can distribute bacteria - filled droplets that suspend them selves in the air and can easily be inhaled into the deepest parts of the lungs, say the scientists from the University of Colorado at Boulder. Since plastic shower heads appear to "load up" with more bacteria- rich biofilms, metal shower heads may be a good alternative, said Professor Pace. Showers have also been identified as a route for spreading other infectious diseases, including a type of pneumonia called Legionnaires’ disease and chest infections with a bacterium called Pseudomonas aeruginosa. Hot tubs and spa pools carry a similar infection risk, according to the Health Protection Agency. Why the shower can cause lung disease
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