There are a number of animals that give off light in some way-including several kinds of insects and fish. Some kinds of mushrooms give off light, too. But most plants don’t give out light. Now, scientists are working to change that.
When a living thing gives off light, it’s called bioluminescence(生物发光). Fireflies are a well-known example of bioluminescence. Though less well-known, many mushrooms are also bioluminescent. These bioluminescent creatures light up thanks to the chemicals called luciferins(荧光素)inside their bodies. Luciferins cause a chemical reaction that can give off light.
Plants don’t naturally have luciferins, so there are no naturally bioluminescent plants. But that hasn’t stopped scientists from trying to create them. In the past, scientists have created plants that made less bright by adding DNA from shining objects. Scientists have also created plants that can give off light by adding luciferins to plants. But it only works as long as the chemicals last. In 2017, a team was able to cause a plant to give off light for about four hours.
Now, researchers at a Russian company have come up with a new method of creating shining plants. By adding certain parts of the DNA from shining mushrooms to ordinary tobacco plants, the researchers were able to create plants that could make their own luciferins. The scientists reported that the light was about 10 times brighter than in earlier shining plants.
The researchers believe that shining plants could help scientists learn more about the way plants work. For example, the moving patterns or waves of light in the plants may show activities in plants that normally can’t be seen. The shining also helps reveal how plants may be affected by things around them. For example, the plants gave off much more light strongly when a ripe banana skin was nearby. But the researchers don’t think the plants will just be used for science. They think many people may want shining plants for their beauty. So they are working with a company to develop shining plants for sale.
1. What phenomenon does the author describe in paragraph 1?| A．Most animals hate giving off light. |
| B．Many plants give off light through scientists’ efforts. |
| C．Animals give off light to protect themselves. |
| D．It’s hard to find plants that give out light. |
| A．It gives off lots of heat to warm itself. |
| B．It has chemical reactions inside its body. |
| C．It lacks energy due to chemical reactions. |
| D．It informs other fireflies of the danger. |
| A．By showing numbers. | B．By making a comparison. |
| C．By providing examples. | D．By making a summary. |
| A．Human development results in less shining plants |
| B．Scientists manage to create shining plants |
| C．People’s lifestyles are reflected in shining plants |
| D．Geography determines the types of shining plants |
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【推荐1】Life beneath the sea surface can be lovely and lively. But many organisms there produce poisonous chemicals to hunters. Divers are now collecting such poisons as drugs for human medicine.
Sharks aren't the scariest things in the ocean for scientists who dive to work. Powerful currents, creating where the ocean floor drops away, can be just as deadly. But the scientists who work underwater are trained to deal with these dangers. The rewards of research and underwater adventures are greater than the risks.
The sea may seem like a strange place to look for new drugs. But organisms in the ocean have had to adapt to a tough environment. The chemicals they make for survival might help people, too. More than 50 years ago, scientists discovered a new anticancer drug in a sea sponge. Since then, researchers have been hunting for more of such useful natural products in the seas.
With the help of underwater robots and small submarines, scientists are searching the seas—from shallow reefs to the ocean's great depths.
Bacteria living in the Arctic's cold waters break down their food using more different ways than organisms on land do. This process of turning food into energy for growth, activities and reproduction is called metabolism (新陈代谢). These pathways also produce chemicals called “secondary metabolites”. One day they also might help people.
During a fouryear project called PharmaSeas, scientists made thousands of extracts from those seafloor samples. In about a dozen of them, researchers found mixtures that can kill bacteria that some of today's antibiotics (抗生素) cannot kill. Three other newfound chemicals reduce epileptic seizures (癫痫病发作) in mice. Yet another compound may reduce the symptoms of Alzheimer's disease.
1. Why do sea organisms produce chemicals?| A．To warn themselves in the sea. | B．To benefit other creatures. |
| C．To change their environment. | D．To struggle for survival. |
| A．Medicinal value. | B．The way of hunting. |
| C．The way of breaking down food. | D．Importance to humans. |
| A．They have the same effects as today's medicine. |
| B．They have unique functions. |
| C．They can treat most diseases. |
| D．They can kill all bacteria. |
| A．Diving for New Medicines | B．Threats from the Ocean |
| C．Future Sources of Bacteria | D．Danger of Diving in the Sea |
【推荐2】Most people don't think too much about chemicals， but actually they are all around us. Many substances consist of chemicals， including the air that we breathe and the water that we drink. Some chemicals are natural， but most of them are artificial and may be harmful to the human body.
In 2005， Hurricane Katrina struck the United States， so displaced people had to move into temporary housing. Later， some of them began experiencing headaches and nosebleeds due to Formaldehyde exposure. This chemical is commonly found in the glue that holds many household products. It was proved to cause cancer in 2011 and has been linked to an increase in allergies it children.
However，there is another choice: natural adhesives（黏合剂）. In particular， one is made from plants such as soy（豆类）proteins that have been changed to resemble the protein some shellfish use to stick to rocks. A natural adhesive is now widely used in wood products in the U.S. Other companies are also developing more natural alternatives to replace industrial chemicals. This is a part of the Green Chemistry philosophy.
Green Chemistry is a way of rethinking how to develop products and processes that are more environmentally-friendly and better for people's health. That includes reducing processing waste， using renewable materials. The 12 Principles of Green Chemistry lay out the goals of this approach. The first is prevention. It is better to prevent waste than to treat it or clean it up. Another principle encourages less dangerous chemical synthesis（化合）. Chemical reactions should be designed to be as safe as possible. Energy efficiency is encouraged as well as using chemicals made from renewable plant-based sources.
There are challenges in meeting and holding to the principles of Green Chemistry， but this will encourage new research and lead to the discovery of new chemistry.
1. Why does the author mentioned the incident that happened in 2005?| A．To make comparisons. | B．To prove a point. |
| C．To introduce a chemical. | D．To bring in the topic. |
| A．Wood from trees | B．Proteins from shellfish |
| C．Processed plant proteins. | D．Melted special rocks |
| A．The definition and purpose of Green Chemistry |
| B．How to make environmentally. friendly products |
| C．Ways to reduce the amount of waste in daily life |
| D．Reasons for promoting Green Chemistry in the world. |
| A．Wonderful but impractical |
| B．Challenging but inspiring |
| C．Admirable and popular. |
| D．Complex and discouraging |
【推荐3】Show Some Love to the Ugly and Endangered
Let’s face it-not every animal is going to win a beauty contest. But all of them are important, and they all deserve a chance at survival. Let’s show a little love for some of the endangered species that may not be the prettiest, but need our help all the same.
Pallid Sturgeon(浅色鲟鱼)
The species has been around for more than 78 million years. These guys once shared the planet with dinosaurs. And sadly，they could be going the same way as their now fossilized(变成化石的)friends. Today, the last wild-born pallid sturgeons are nearing extinction. As humans built dams in the waterways these fish need to survive, they blocked the pallid sturgeon from being able to reach its breeding grounds.
California Condor(加州秃鹫)
The California condor sports a bare featherless head, the better to put into dead things without getting too dirty. With a wingspan of up to 9 feet, they’re one of the largest birds in the world. But due in large part to habitat loss, illegal shootings, and lead poisoning, by 1985 the entire known wild population had been reduced to just nine birds.
Northern Long-eared Bat
Few animals have as undeserved a bad reputation as bats do but they actually provide incredibly valuable services like pollination(授粉)or eating insects that could otherwise kill crops or make us sick.
North American bats like the Northern long-eared bat are being killed right now by a disease called “white nose syndrome”. This infection has lent new urgency to efforts to protect bat habitats and reduce other threats to their survival.
These are just three of a long list of endangered species that need our help-even if they aren’t always the ones that get the lion’s share of the spotlight. This Valentine’s Day, show some love for species like these.
1. What is the main reason for the pallid sturgeon’s close extinction?| A．Its ugly appearance. |
| B．The extinction of its fossilized friends. |
| C．Its long history of more than 78 million years. |
| D．Dams prevent them from reaching breeding grounds. |
| A．Bats deserve a bad reputation. |
| B．North American bats are being killed by “white nose syndrome”. |
| C．The California condor sports featherless. |
| D．The California condor is the largest birds in the world. |
| A．No animal can share the spotlight of the lion. |
| B．Few endangered species need human’s help. |
| C．All species are equally important. |
| D．The Valentine’s Day is intended for endangered species. |
【推荐1】In many countries of the world, people can confidently tell you the meaning of their town or city, but most people who live in Manchester, Oxford or Birmingham would not be able to explain what the name of their city means. The name of every British town and city, however, has a long history.
Two thousand years ago, most people living in Britain were Celts. Even the word “Britain” is Celtic. Then the Romans arrived and built camps which became cities called “castra”. This is why there are so many place names in England which end in “-chester” or “-caster” – Manchester, for example.
After the Romans left Britain, it was attacked by tribes (部落) called the Anglo-Saxons who were from the area of Europe that is now Germany and Holland. Without the Roman army, it was impossible to protect the country from these people. The names of their villages often ended in “-ham” or “-ton”. Some got their name from the leader of the village, so Birmingham, for example, means “Beormund’s village”.
Twelve hundred years ago, the Vikings came to England from Scandinavia. They traded with the Anglo-Saxons but lived in their own villages. These often ended in “-by” or “-thorpe”. The name “Kirkby” means “a village with a church” and Scunthorpe was the village of a man called Skuma.
Finally, in 1066, England became Norman – the Normans gave us the place name “grange”, which means farm.
And how about London? Experts cannot agree. The Romans called the city Londinium, but they were not the first inhabitants (居民). People once believed that the United Kingdom’s capital city got its name from the castle of a King called Lud, but this is very unlikely. Our best guess today is that the name comes from a Celtic word meaning a fastflowing river. Like a number of British place names, its history is lost in time.
1. The origin of British place names is unfamiliar to many local people because of ______.| A．the death of ancient languages | B．their lack of interest in the names |
| C．the long lost history of the names | D．the frequent changes to the names |
| A．The Celts — The Romans — The Vikings — The Normans — The Anglo Saxons |
| B．The Celts — The Romans — The Anglo Saxons — The Vikings — The Normans |
| C．The Romans — The Celts — The Vikings — The Anglo Saxons — The Normans |
| D．The Romans — The Anglo Saxons — The Celts — The Normans — The Vikings |
| A．It is short for Londinium. | B．It’s from the term for a river. |
| C．It is puzzling and hard to confirm. | D．It comes from the castle of a King. |
【推荐2】Each year, the women of Olney and Liberal compete in an unusual footrace. Dressed in aprons(围裙)and headscarves,they wait at both towns-starting lines.Each woman holds a frying pan with one pancake inside. At the signal,the women flip(抛)their pancakes and they're off!
This “pancake racing”tradition is said to have started on Shrove Tuesday, 1445, in Olney. Shrove Tuesday is the day before the Christian season ofLent(大斋戒)begins.During Lent,many people decide to give up sugary or fatty foods.
Legend says that in 1445, an OIney woman was making pancakes to use up some of her sugar and cooking fats before Lent. She lost track of time and suddenly heard the church bells ring. signaling the beginning of the Shrove Tuesday serviceRealizing that she was going to be late for church, she raced out, still wearing her apron and headscarf and holding her frying pan with a pancake in it.
In the following years, the woman’s neighbors imitated(模仿)her dash to church and pancake racing was bon.Olney women continue this Shrove Tuesday tradition more than 500 years later.
In 1950, inspired by a picture of the OIney Pancake Race in a magazine, a resident of Liberal wanted his town to join in the fun.He called Olney to set up a friendly competition,and the people of Olney accepted.
The rules are simple. Racers must wear the traditional headscarfand apron. They must flip their pancakes twice once before starting and once after crossing the finish line.After the race, there are Shrove Tuesday church services.Then Liberal and Olney connect through a video call to compare race times and declare a winner.
In both towns, the races have grown into larger festivals. OIney's festival is an all-day event starting with a big pancake breakfast.Liberal's festival lasts four days, including a parade(游行)，a talent show, and contests that feature eating and flipping pancakes.
1. What can we know about Olney Pancake Race?| A．It begins during Lent. |
| B．It was founded by a Olney woman. |
| C．It has been held annually since 1445. |
| D．Its origin can date back to 15th century. |
| A．Wear their own clothes. | B．Hold the pancake all the way. |
| C．Throw and catch the pancake twice. | D．Have the pancake cooked while running. |
| A．Olney's festival is held for four days. |
| B．Liberal’s festival has varieties of activities |
| C．Olney’s festival has more various competitions. |
| D．Liberal’s festival starts with a delicious breakfast. |
| A．Positive. | B．Negative. | C．Objective. | D．Subjective. |
【推荐3】A company in San Francisco, California, has found a way to turn used plastic bottles into women's shoes. Every day, millions of Americans drink water and other liquids from plastic bottles. More than 60 million of them are thrown away each day. Many of the plastic bottles end up in landfills or are burned with other waste products.
A San Francisco-based company called Rothy's, however, turns this plastic waste into environmentally friendly shoes. Roth Martin is the company's co-founder. He explains how they turn plastic into soft material for women's feet. They take plastic, clean it, and break it down into small pieces. Then they press them through a device that makes soft fibers. Those fibers are then bonded together. This is done by a 3-D machine. It is designed to reduce waste while people are making the shoes. The knitted stuff and the inner part of the shoe are then attached to the shoe's outer part called the sole（鞋底）. This outer sole is also made from environmentally friendly material: responsibly sourced no-carbon rubber.
Rothy's shoes are sold online. They are flat shoes, with either a rounded or pointed toe. They come in different colors and designs. They cost either $ 125 or $ 145 per pair, depending on the design. After American actress Gwyneth Paltrow discovered them, the demand for the shoes grew. Martin says there is no shortage of material to fill that demand. “We're not going to run out of water bottles any time soon, so we have a limitless supply of material, and I think that is a good sign for our future.” When the environmentally friendly shoes wear out, customers can return them at no cost to a company that uses the recycled material to make other products.
For now, the shoes are only available to be shipped in the United States. However, the company says it will add international shops in the near future.
1. How are used plastic bottles usually dealt with?| A．They are used to make shoes. |
| B．They are buried or burned. |
| C．They are changed into soft material. |
| D．They are returned to factories for reuse. |
| A．Combined. | B．Fixed. |
| C．Spotted. | D．Repaired. |
| A．The design and color. |
| B．The reasonable price. |
| C．The power of famous people. |
| D．The company's advertisement. |
| A．To advertise a new kind of shoes. |
| B．To describe the process of making shoes. |
| C．To introduce a new way of recycling plastic waste. |
| D．To stress the importance of environmental protection. |
【推荐1】There’ s no place like home. It’ s the place where we’ re surrounded by our possessions and creature comforts. We purchase things to give our homes a personal touch. And one thing we’re buying more of is houseplants. But are these “living” additions to our homes good for us and the environment?
Houseplants, also known as pot plants, add a natural touch and they have the ability to brighten up a room on a budget. The Royal Horticultural Society found that nearly 72% of adults in the UK had a houseplant in their home, with this figure rising to 80% of 16-24 year olds. A fifth of owners also said they use plants in the home to boost their health and well-being. And average sales last year were up on the previous year.
It seems millennials (千禧代) are driving the growth in the sales of houseplants. More young people are living in flats without a garden. 24-year-old Daisy Hale said “being able to care for something but not having too much commitment—I guess that’s a classic millennial line—is ideal for my lifestyle.”
From hanging baskets, to cacti (仙人掌) and succulent ferns, the choice of vegetation is endless. They are easy to care for, and there have been unproven claims that they improve the air quality in our home. But whatever their benefits, there are now concerns that they might not be so good for the environment. Some are bought online and shipped from overseas. Fay Kenworthy, co-founder of PlantSwap, a community activity that encourages people to trade plants locally, said “this could defeat many local plants.”
But botanist James Wong argues that home delivery has less of an environmental impact than multiple trips to the garden center in a car. Although he’ s not too concerned about the environmental impact, others are worried about the plastic pots they are in and the type of peat (泥炭) that some of them are grown in. However, a sustainable approach to buying them may be the best way forward if we want to introduce some natural greenery into our homes.
1. What is the benefit of a houseplant?| A．A houseplant can cure people of many diseases. |
| B．A houseplant is ideal for millennials’ career. |
| C．A houseplant improve the water quality in our home. |
| D．A houseplant can beautify a room with little money. |
| A．The choice of vegetation is endless. | B．People should buy local plants. |
| C．It’s best to buy plants online. | D．Houseplants are hard to care for. |
| A．A fashion magazine. | B．A tour brochure. |
| C．A scientific fiction. | D．A history book. |
| A．Negative. | B．Neutral. | C．Positive. | D．Not mentioned. |
| A．Natural Greenery | B．Millennials’ Choice |
| C．Houseplants: Good or Bad? | D．Hanging Baskets or a Garden? |
【推荐2】Saving Seeds for Next Year’s Flower Garden
Just like vegetable seeds (种子), you can save flower seeds from your garden this year to plant in the following year.
If you want the same kind of flower or plant for next year’s garden, collect only the seeds from plants marked as “heritage”.
Even if you expect plants to be the same as their parents, it is not certain. Wind or insects could bring pollen from one plant to another and accidentally create a mixture.
Just like everything else in gardening, timing is important. Collect seeds on a dry, sunny day.
For plants like sunflowers, cut the head off the plant and drop it into a paper bag.
You can place the seeds in a glass box that can be sealed. Then store them in a cool, dry area. Make sure to mark your glass box so you do not forget what they are.
| A．Keep an eye on some flowers. |
| B．Let the seeds grow and fall naturally. |
| C．Give the bag a shake to help separate the seeds. |
| D．When stored with care, seeds are good for several years. |
| E．These kinds of plants will grow just like their parent plant. |
| F．In this case, add more seeds to the soil to make sure that some will grow. |
| G．You can avoid this by planting only the plant from which you plan to collect seeds. |
【推荐3】More than 10 years ago, it was difficult to buy a tasty pineapple. The fruits that made it to the UK were green on the outside and, more often than not, hard with an unpleasant taste within. Then in 1966, the Del Monte Gold pineapple produced in Hawaii first hit our shelves.
The new type of pineapple looked more yellowy-gold than green. It was slightly softer on the outside and had a lot of juice inside. But the most important thing about this new type of pineapple was that it was twice as sweet as the hit-and-miss pineapples we had known. In no time, the Del Monte Gold took the market by storm, rapidly becoming the world's best-selling pineapple variety, and delivering natural levels of sweetness in the mouth, up until then only found in tinned pineapple.
In nutrition it was all good news too. This nice tasting pineapple contained four times more vitamin C than the old green variety. Nutritionists said that it was not only full of vitamins, but also good against some diseases. People were understandably eager to be able to buy this wonderful fruit. The new type of pineapple was selling fast, and the Del Monte Gold pineapple rapidly became a fixture in the shopping basket of the healthy eater.
Seeing the growing market for its winning pineapple, Del Monte Gold tried to keep market to itself. But other fruit companies developed similar pineapples. Del Monte Gold turned to law for help, but failed. Those companies argued successfully that Del Monte Gold's attempts to keep the golden pineapple for itself were just a way to knock them out the market.
1. What is the new type of pineapple like?| A．A little soft outside and sweet inside. |
| B．Good-looking outside and soft inside. |
| C．Yellowy-gold outside and hard inside. |
| D．Green outside and sweet inside. |
| A．It was developed by Del Monte Gold . |
| B．It was less sweet and good for health. |
| C．It was rich in nutrition and tasted nice. |
| D．It was used as medicine. |
| A．that people enjoy eating | B．that people use as a gift |
| C．that is difficult to get | D．that is always present |
| A．Del Monte Gold allowed other companies to develop pineapples. |
| B．Del Monte Gold tried hard to control the pineapple market. |
| C．Del Monte Gold succeeded in keeping the pineapple for itself. |
| D．Del Monte Gold argued with the other companies. |
