1 . Human beings are not alone in having invented vaccination, while honeybees got there first and they can run what look like vaccination programmes, which has been confirmed by Gyan Harwood of the University of Illinois, Urbana-Champaign.
Queen bees vaccinate their eggs before they are laid. But the question is how the queen receives her antigen supply, for she lives purely on royal jelly, a substance secreted by nurse bees when they are in the life stage of feeding the young. Dr Harwood wondered if the nurses combined the royal jelly they produced with pieces from pathogens they had consumed while eating something brought in from outside.
To test this idea, they collected about 150 nurse bees and divided them among six queenless mini hives equipped with the young to look after. They fed the nurses on sugar-water, and for three of the hives they added Paenibacillus larvae, a bacterium causing a disease, to sugar-water.
Dr Harwood and Dr Salmela labeled the bacteria with a certain dye, to make them easy to track. And, sure enough, microscope confirmed that Paenibacillus larvae were getting into royal jelly secreted by those bees which had been fed with the sugar-water. Moreover, examination of this royal jelly revealed higher levels of defensive substance, compared with royal jelly from bees that had not been mixed with Paenibacillus larvae. This substance is thought to help bee immune systems fight against bacterial infections.
All told, these findings suggest that nurse bees are indeed, via their royal jelly, passing antigens on to the queen, then into eggs. They also mean, because the young receive royal jelly for the first few days after they hatch, the nurses are giving the young the second antigens. Each young bee is therefore being vaccinated twice.
1. What puzzled Dr Harwood from paragraph 2?A.What the royal jelly consists of. |
B.Where nurse bees receive pathogens. |
C.How the antigen come into the queen bees' bodies. |
D.Whether honeybees run vaccination earlier than man. |
A.By dividing bees into different roles. |
B.By keeping track of the special bacterium. |
C.By changing the components of royal jelly. |
D.By observing nurse bees' different behaviors. |
A.Nurse bees are the key to vaccination for bee group. |
B.The nurse bees pass the antigen only to the queen. |
C.Bacteria-used royal jelly has fewer defense substances. |
D.Two vaccinations are given to young bees by caregivers directly. |
A.A pet guide. | B.A social website. |
C.An official document. | D.A medical magazine. |
Pets aren’t just hairy toys for your children. Recently it
Pets often act as
China has recently announced the formal establishment of its first five national parks. Giant Panda National Park (GPNP)is one
The giant panda is a famous symbol of China and one of the most adorable
Connecting these reserves and establishing protected areas between
The
Ant Forest,
The award is the United Nation’s highest environmental honor and was given to Ant Forest for encouraging more than half a billion people to adopt an eco-friendly and greener lifestyle,
Alipay achieved this remarkable feat by inspiring
The proposal of Ant Forest is also in line
5 . In 2016, the world’s population cast aside 49 million tons of electronic waste, known as e-waste.
It has been calculated that this number will grow to more than 60 million tons by 2021.
What is causing the upsurge ( 激增 ) in e-waste? Technology is becoming more and more widespread, covering almost every aspect of our lives. Meanwhile, the lifespan of devices is getting shorter---many products will be thrown away once their batteries die, to be replaced by new devices. Companies intentionally plan the obsolescence ( 过时 ) of their goods by updating the design or software and discontinuing support for older models, so that now it is usually cheaper and easier to buy a new product than to repair an old one. Since prices are falling, electronic devices are in demand around the world.
As more people buy electronic equipment, manufacturers ( 制造商 ) are beginning to face shortages of the raw materials needed to make their products, so recycling and reusing materials from discarded products and waste makes economic and environmental sense.
Recycling e-waste is practiced both formally and informally. Proper or formal e-waste recycling usually involves taking apart the electronics, separating and sorting through the materials and cleaning them. Companies must obey health and safety rules to reduce the health and environmental hazards of handling e-waste by using pollution-control technologies. All this makes formal recycling expensive. Informal recycling is typically unlicensed and uncontrolled. At informal recycling workshops, men and women recover valuable materials by burning devices to melt away non-valuable materials. Usually they do not wear protective equipment and lack any awareness that they are handling dangerous materials.
With the amount of e-waste growing around the world, recycling alone will not be enough to solve the problem. In order to reduce e-waste, manufacturers need to design electronics that are safer, and more durable, repairable and recyclable. The best thing you can do is resist buying a new device until you really need it. Try to get your old product repaired if possible and, if it can’t be fixed, resell or recycle it responsibly. Before you recycle your device, put any broken parts in separate containers and close these tightly to prevent chemicals from leaking. Wear latex gloves and a mask if you’re handling something that’s broken.
1. How do companies contribute to the rapid growth of e-waste?A.They sell their new products at extremely low price. |
B.They plan a short lifespan for the batteries intentionally. |
C.They do not provide support for old model on purpose. |
D.They update the design and software to cover every aspect of our lives. |
A.harm | B.problems | C.concern | D.protection |
A.manufacturers | B.consumers | C.managers | D.salesmen |
A.to call for everyone to play a part in reducing e-waste |
B.to promote a style of living without electronic devices |
C.to explain why manufacturers need to recycle e-waste |
D.to appeal to the companies to sell less devices |
6 . When the Chinese spacecraft Chang’e-5 returned to Earth on December 17, 2020, it brought back something not seen on our planet since the 1970s: moon rock samples. This precious cargo, collected by Chang’e-5’s robotic research vehicle in the northwest region of the lunar near side, is now being studied by scientists in Beijing. The success of the latest Chinese space mission also showcased technology that may be used in future years to create human settlements on Earth’s near neighbor.
The returned lunar samples will “absolutely add new knowledge of the history of the moon, particularly its volcanoes,” says Xiao Long, a planetary scientist at China University of Geosciences. The rocks sent back by Chang’e-5 “will ask us to rethink about why and how the moon’s volcanic history lasted this long,” he says.
The Chang’e-5 mission was more than just a trip to collect moon rocks. It was also the latest stage of a long, planned sequence of robotic lunar explorations by China that have grown ever more scientifically advanced.
The program began with the 2007 launch of Chang’e-1 and Chang’e-2 three years later. These craft circled the moon collecting data used to help guide Chang’e-3 and Chang’e-4, the first Chinese spacecraft to land on the moon surface, and to direct their robotic vehicles. The robot on Chang’e-5 was able to collect rock and soil samples and return them to Earth. In the near future, an identical spacecraft called Chang’e-6 will attempt a sample-return mission from the moon’s south pole—an area of intense scientific interest-given the large amount of water ice present.
The more advanced Chang’e-7 and Chang’e-8 spacecraft are also planned to land near the south pole to carry out analysis of the region and test new technologies, including detecting and obtaining materials that could be useful to future human explorers, such as water and hydrogen, and testing 3D printing on the lunar surface.
The long-term aim of the Chang’s program is to establish an International Lunar Research Station around 2030 to support robotic and, eventually, crewed missions.
1. What is paragraph 2 mainly about?A.The moon’s recent volcanic activities. | B.The significance of the moon rock samples. |
C.New knowledge of the history of the moon. | D.Further studies of the returned lunar samples. |
A.The technology they use. | B.The time they spend on the moon. |
C.The specific locations they explore. | D.The amount of material they bring back. |
A.transport researchers to the moon station |
B.build up an International Lunar Research Station |
C.collect data necessary to guide moon-landing spacecraft |
D.find and test resources and means to support living on the moon |
A.A project to study the surface of the moon. |
B.A plan to improve human settlements on the moon. |
C.A set of experiments to test the possibility of manned spacecraft. |
D.A series of increasingly challenging scientific lunar explorations. |
7 . Masks that helped save lives are proving a deadly danger for wildlife, with birds and sea creatures trapped in the shocking number of thrown-away facial coverings. Single-use masks have been found around pavements, waterways and beaches worldwide. Worn once, the thin protective materials can take hundreds of years to decompose. “Face masks aren't going away any time soon—but when we throw them away, these items can harm the environment and the animals,” Ashley Fruno of animal rights group PETA said.
In Britain, a gull was rescued by the RSPCA after its legs became tangled in the straps of a mask for up to a week. The animal welfare charity took it to a wildlife hospital for treatment before its release.
The biggest impact may be in the water. More than 1.5 billion masks made their way into the world's oceans last year, accounting for around 6,200 extra tonnes of ocean plastic pollution, according to environmental group Oceans Asia.
Conservationists in Brazil found one mask inside the stomach of a penguin after its body was washed up on a beach, while a dead pufferfish was discovered caught inside another off the coast of Miami. French campaigners found a dead crab trapped in a mask near the Mediterranean. Masks and gloves are “particularly problematic” for sea creatures, says George Leonard, chief scientist from NGO Ocean Conservancy. “When those plastics break down in the environment, they then enter the food chain and impact entire ecosystems.” he added.
There has been a shift towards greater use of reusable cloth masks as the pandemic has worn on, but many are still using the lighter single-use varieties. Campaigners have urged people to bin them properly and cut the straps to reduce the risk of animals becoming trapped. Oceans Asia has also called on governments to increase fines for littering and encourage the use of washable masks.
1. What's Paragraph 1 mainly about?A.The problem of littering masks. | B.The long time to break down masks. |
C.The threat of masks to wildlife. | D.The protective use of masks to people. |
A.They gave first aid to the bird. | B.They released the bird at once. |
C.They kept the bird for about a week. | D.They sent the bird to hospital. |
A.By providing examples. | B.By giving explanations. |
C.By making comparisons. | D.By analyzing causes. |
A.Forbidding the use of single-use masks. | B.Wearing reusable cloth masks. |
C.Cutting the masks up before throwing. | D.Increasing fines for binning masks. |
8 . Lonely Planet Trips
Here are some travel destinations by Lonely Planet. Reading them, you’ll be in a flash.
Bhutan
The Kingdom of Bhutan, located on the Silk Road in South Asia, claimed the No. 1 spot partly for its majestic beauty and because it had become the first fully organic nation by 2020. The kingdom has lush subtropical plains in the south and sub-alpine Himalayan mountains in the north, which include Gangkhar Puensum, Bhutan’s highest peak and is believed to be the highest unclimbed mountain in the world.
North Macedonia
If you want an alternative to Europe's more popular travel spots, North Macedonia could be for you. Its mountains and their trails are “blissfully quiet” and the locals are “unfailingly helpful” according to Lonely Planet. Among its destinations is Ohrid, a charming, old town dotted with medieval ruins and churches, lined with cobblestone streets, and overlooking Lake Ohrid.
Eswatini
The kingdom offers multitudinous climate and topography differences, and is known for its wide varieties of wild animals, which include more than 500 bird species and 107 mammal species. The nation has seven nature reserves, four frontier conservation areas and three wildlife reserves.
Costa Rica
Costa Rica is beloved for many reasons, from its coffee to its epic surfing. It’s also notable for its reliance on green energy sources. In fact, 90% of its energy is created by regenerative sources such as wind and hydro. It is also one of the world’s most biodiverse countries — home to half a million species. Of course, no trip to Costa Rica is complete without a visit to the Sloth Sanctuary.
1. What can tourists appreciate in both Bhutan and North Macedonia?A.Organic products. | B.Subtropical jungles. |
C.Medieval architecture. | D.Mountain scenery. |
A.Pleasant quietness. | B.Topography varieties. |
C.Abundant wildlife. | D.Cobblestone streets. |
A.Renewable resources. | B.Biodiverse plants. |
C.Frontier preserves. | D.The Silk Road. |
9 . Hidden beneath the surface in the roots of Earths astonishing and diverse plant life, there exists a biological superhighway linking together the members of the plant kingdom in what researchers call the "wood wide web".
The network is comprised of thin threads of fungus (真菌) that grow outwards underground up to a few meters from its partnering plant, meaning that all of the plant life within a region likely connected to one another. The partnership is beneficial for both parties involved, plants provide carbohydrates (碳水化合物) to the funguses and in exchange, the funguses aid in gathering water and providing nutrients to its partnering plant.
A study conducted by Rensen Zeng of the South China Agricultural University found that this also allowed for plants to warn one another of potential harm. The study showed Broad Beans used the fungal network to spy on one another for upcoming danger.
Like our Internet, this fungal connectivity is also full of crime. Some plants, such as Golden Marigolds have been found to release poisons into the network to slow down the growth of surrounding plants in the fight for water and light. Other plants, such as the Phantom Orchid, do not have the chlorophyll (叶绿素) and must get the necessary nutrients from surrounding plants.
Research suggests that animals such as insects and worms may be able to detect slight exchanges of nutrients through the network, allowing them to more easily find delicious roots to feed on; however, this has not been conclusively made clear in experimentation. The more we learn about this phenomenon, the more our understanding of the plant life of our planet will continue to change. Perhaps one day, we may be able to map out these complex networks entirely.
1. What is the function of the first paragraph?A.To explain the aim of the web. |
B.To introduce the main topic. |
C.To give definition of diverse life. |
D.To show the importance of plants. |
A.compete for survival |
B.gather more water |
C.take in sunlight |
D.break natural rules |
A.Animals can also feed on the fungus. |
B.Nutrient exchanges are too slight to detect. |
C.No experiment can prove the phenomenon. |
D.More needs to be done to work out the network. |
A.The Partnership between Plants |
B.The Unknown Roots of the Earth |
C.The Superhighway Linking the Plants |
D.The Mysterious Map Changing the World |
10 . London is considered as one of the greatest cities on Earth. From historical sites to the modern-day metropolis, it can seem an infinite feast of activities and possibilities. For the budget-minded traveler, London might not appear to be the most wallet-friendly destination.
One of the most surprisingly free things to do in London is visit top museums and art galleries.
London has a long history of influencing the musical world, and the wise traveler knows that concerts are some of the best free things to do here in various seasons. Particularly in the summer, free concerts are available along the banks of the Thames River, and frequently advertised in entertainment guides.
While London is full of exciting opportunities for the luxury traveler, it doesn't exclude those on a budget. The free things to do in London will often help travelers escape from the tourist attractions and catch a look at local life.
A.However, this is not the case. |
B.Literary lovers will find many free things to do in London. |
C.That's because London is among the world's priciest cities. |
D.The National Gallery is free to visitors favoring world-class paintings. |
E.Even in winter, certain areas are usually crowed with musicians and performers. |
F.Nobody can refuse such charming music with the beautiful sceneries along the river. |
G.Combining them with some well-chosen costly additions will give you a balanced look at the beautiful city. |