5 . Researchers continue to show the power behind our sense of smell. Recent studies have found, among other things, that the smell of foods like pizza can cause uncontrollable anger in drivers on roads.

The review explains that smell is unique in its effects on the brain. According to Conrad King, the researcher who carried out the review, "more than any other senses, the sense of smell goes through the logical part of the brain and acts on the systems concerned with feelings. This is why the smell of baking bread can destroy the best intentions of a dieter."

Smell, which dictates the unbelievable complexity of food tastes, has always been the least understood of our senses. Our noses are able to detect up to 10,000 distinct smells. Our ability to smell and taste this extremely large range of smells is controlled by something like 1,000 genes (基因), which make up an amazing 3% of the human genome. Researchers Richard Axel and Linda Buck were together awarded a Nobel Prize in 2004 for their ground-breaking research on the nature of this extraordinary sense. These two scientists were the first to describe the family of 1,000 olfactory (嗅觉) genes and to explain how our olfactory system works.

According to one study in the research review, smelling fresh pizza or even the packaging of fast foods can be enough to make drivers feel impatient with other road users. They are then more likely to speed and experience uncontrollable anger on roads. The most reasonable explanation is that these can all make drivers feel hungry, and therefore desperate to satisfy their appetites.

In contrast, the smells of peppermint and cinnamon were shown to improve concentration levels as well as reduce drivers’ impatience. Similarly, the smells of lemon and coffee appeared to promote clear thinking and mental focus.

However, the way genes regulate smell differs from person to person. A study by researchers in Israel has identified at least 50 olfactory genes which are switched on in some people and not in others. They believe this may explain why some of us love some smells and tastes while others hate them. The Israel researchers say their study shows that nearly every human being shows a different pattern of active and inactive smell-detecting receptors.

The skin is an essential part of your body and the    1     (large) organ of it. You have three layers of skin    2    act as a barrier against disease, poisons and the sun's harmful rays. The functions of your skin are also very complex: it keeps you warm or cool it prevents your body from    3    (lose) too much water; it is where you feel cold, heat or pain and it gives you your sense of touch.

From ancient myth(神话) to modern research, left-handed people have been labeled    1    society-for good and bad. Nowadays, “lefties” are     2    (general) believed to be more talented.

According to Live Science, about 10 percent of the world’s population is left-handed. However, nobody has been quite sure     3    determines a person’s dominant hand. In a new study published on Sep 5 in the journal Britain, scientists have pinpointed for the first time the part of our DNA that     4    (relate) to left-handed.

8 . Your teeth may be part of your smile,_______they have a more important job—they are the first step in the process of digestion. You have three _________(kind) of teeth. In the very front of your mouth are eight flat, thin teeth called incisors. They are used for cutting and biting food. Next to these are pointed teeth called canines, _________ also help you tear food. The remaining teeth are molars. These teeth have flat tops for crushing and grinding the food.

9 . Did The Earth Move For You?

Eleven-year-old Angela suffered from a disease involving her nervous system. She was unable to________and her movement was restricted in other ways as well. The doctors did not hold out much _______of her ever recovering from this illness. They ________she‟d spend the rest of her life in a wheelchair. They said that ______, if any, were able to come back to normal after catching this disease. But the little girl was brave and confident. There, lying in her hospital bed, she would ______to anyone who‟d listen that she was definitely going to be walking again someday.

She was then sent to a specialized rehabilitation hospital in the San Francisco Bay area. Whatever therapies(治疗方法) could be ________to her case were used. Things didn‟t work as the therapists expected. Still they were charmed by her _________spirit. They taught her about ____________—   about   seeing   herself   walking.   If   it   would   do   nothing   else,   it   would ______give her hope and something _______to do in the long waking hours in her bed. Angela would work as hard as possible in physical therapy, in whirlpools and in exercise sessions. And she worked just as hard lying there ______doing her imaging, visualizing herself moving, moving, moving!

One day, as she was twisting with all her _____to imagine her legs moving again, it seemed as though a _____thing happened: The bed moved! It began to move around the room! She _________out, “Look what I‟m doing! Look! Look! I _________it! I moved!”

Of course, at this very moment everyone else in the hospital was screaming, too, and running   for ______. People   were   screaming,   equipment   was _______and   glass   was breaking. You see, it was the recent San Francisco earthquake. But don‟t tell that to Angela. She‟s _________that she did   it. And now only a   few years   later, she‟s back   in school.

______her own two legs. No crutches(拐杖), no wheelchair. You see, anyone who can shake the earth between San Francisco and Oakland can conquer a little disease. You never know what‟s around the corner until you take a _________step.

10 . Researchers at Brigham found about one in five teenagers now have some degree of hearing damage. The researchers did not say why hearing loss has risen, but other experts have strong suspicions. One likely culprit, they say, is MP3 players.

An MP3 player can be dangerous to hearing when its decibel level is turned up too high. High-decibel sounds can damage nerve endings, called hair cells. If a sound is loud enough, the damage can be permanent. A loud sound can shake the membrane (薄膜) on which the hair cells sit- “like an earthquake”. That shake can break or even uproot hair cells. When that happens, the hair cells are finished. Human ears cannot regrow hair cells. Therefore, when listening to an MP3 player, set a volume limit and avoid exposure to loud sounds.

On the other hand, the loudness of today’s music may not be totally under your control. Music companies have been purposely turning up the volume. It’s a trend called the fight for loudness.

Play a CD from the 1990s. Then play a newly released tune. Don’t touch the volume control. You’ll probably notice that the new CD sounds louder than the old one. Why? Sound engineers who create CDs are using dynamic range compression (压缩), a technology that makes the quiet parts of a song louder and the loud parts quieter. The overall effect of compression is a louder recording.

Many musicians and sound engineers aren’t pleased. They say that compression is driving down the quality of today, s music, making it sound flat and blaring. Gray Hobish, a sound engineer, explains that music should be a combination of loudness and softness. But music companies want to make music louder so it will stand out. That’s important in the competition among recording companies.

What about listeners? Many teenagers listen to music on the go in noisy places and through headphones, all of which reduce sound quality. So young listeners may not notice the poorer quality of modem recordings. “To their ears,” says Hobish, “the music sounds fine. And they are not aware of the hidden threat of the music they are enjoying.”