A recent study found that the nutritional quality of Icelandic Spirulina algae (螺旋藻) produced by a cutting- edge biotechnology system in Iceland, is superior to that of beef in terms of protein, essential fatty acids, and iron, and can serve as a healthy, safe, and more sustainable substitute to meat in daily diets.
According to the study, for every kilogram of beef meat replaced with Icelandic Spirulina, consumers will save some 1,400 liters of water, 340 square meters of fertile land, and nearly 100 kilograms of greenhouse gases emitted into the atmosphere. Moreover, the algae may be consumed in different forms, including as wet biomass, or in the form of paste, powder, or pill. For example, one can use Icelandic Spirulina powder as an ingredient in pasta, pancakes, and pastries, or drink an Icelandic Spirulina shake.
While the role of meat in human diets has been helpful, its ecological footprint is considerable and harmful. Raising beef cattle requires arable lands and feeds, and emits greenhouse gases into the atmosphere, contributing to climate change and global warming. As the demand for animal-source proteins grows, so do the damages caused by the animal breeding. As a response, humanity is searching for novel ways to ensure its nutritional security.
Algae, especially Spirulina, are considered among the most effective food producers on Earth and can be cultivated using different techniques. It is an autotrophic organism (自养生物) and is dependent on photosynthesis (光合作用) and a supply of carbon dioxide. Thus, unlike many other alternative protein sources, cultivating this food source removes greenhouse gases from the atmosphere and reduces climate change.
Dr. Asaf Tzachor, leading researcher of the study, stressed: “Nutritional security, climate change reduction, and climate change adaptation can go hand in hand. All consumers must do is adopt a bit of Icelandic Spirulina into their meals and diets instead of beef meat. It’s healthier, safer, and more sustainable. Whatever change we wish to see in the world should be clearly shown in our dietary choices.”
1. What can we learn about Icelandic Spirulina algae?| A．It contains more nutrients than beef. | B．It is consumed only as a dish. |
| C．It is environmentally friendly. | D．It grows in lakes in Iceland. |
| A．The cause of global warming. | B．The source of greenhouse gases. |
| C．The conditions of raising beef cattle. | D．The negative effects of raising beef cattle. |
| A．Pay attention to food safety. | B．Keep a balanced diet. |
| C．Cultivate sustainable food crops. | D．Make wise choices in daily diet. |
| A．Unlocking the Secret of Spirulina | B．Replacing Beef With This |
| C．More Vegetables, Less Meat | D．A Super Biotechnology System |
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【推荐1】People and other great apes are known for their willingness to help others in need, even strangers. Now, researchers have shown for the first time that some birds-specifically African grey parrots-are similarly helpful.
"We found that African grey parrots voluntarily help familiar parrots to achieve a goal, without obvious immediate benefit to themselves," says Desiree Brucks of the Max Planck Institute for Birds Study, Germany.
Parrots and crows are known for having large brains relative to the size of their bodies and problem-solving skills to match. For that reason, they are sometimes considered to be“feathered apes," explains Brucks. However, earlier studies showed that, despite(尽管)their impressive social intelligence, crows don't help other crows. In their new study, Brucks and his fellows wondered: what about parrots?
To find out, they placed pairs of grey parrots and blue-headed parrots in boxes alongside each other with a transfer(转移)hole between the two, and a hole facing a human experimenter that was either kept open or closed. Both parrot species quickly learned that they could exchange tokens(筹码)with the experimenter for a nut treat-but only the grey parrots helped their neighbors when their own hole facing the scientist was closed, preventing them from gaining any personal reward.
In the very first round, seven out of eight grey parrots were willing to transfer tokens in their possession to their neighbors so that their friends could feast when they could not. The fact that they did so without knowing they would later be tested in the other role showed that those giving were not expecting the favor to be rewarded, said Brucks.
Significantly, the grey parrots appeared to understand the nature of the task, instead of acting out of playfulness. When they saw the other parrot had an opportunity for exchange, they'd pass a token over-but otherwise, they would not. And, like humans, the grey parrots appeared to favor their friends, sharing more tokens with birds they had previously closely associated with, though they still gave some to those they are familiar with.
1. Parrots are considered "feathered apes" mainly due to .| A．their brain size | B．their body structure |
| C．their language skills | D．their intelligence level |
| A．To learn how parrots take on their tasks. | B．To discover whether parrots are helpful. |
| C．To prove parrots are socially active birds. | D．To find out links between apes and crows. |
| A．Parrots passed their tokens through it. | B．Parrots got their rewards through it. |
| C．Researchers exchanged tokens through it. | D．Researchers fed the parrots through it. |
| A．They are naturally interested in playful tasks. |
| B．They rarely build friendship with their neighbors. |
| C．They use tokens to get favors from their neighbors. |
| D．They are more likely to help their friends if possible. |
【推荐2】Millions of years ago dinosaurs lived on the earth. In the days of dinosaurs the whole earth was warm and wet. There were green forests and they could find enough to eat. Later, parts of the earth became cold and dry, and the forests there died. Then dinosaurs could not find enough to eat. This must be one reason why dinosaurs died out.
We can guess another reason. New kinds of animals came on the earth. Some had big brains and were fast and strong. They could kill dinosaurs.
There may be other reasons that we don’t know about yet. Scientists are trying to make more discoveries about dinosaurs.
Dinosaurs have many sizes and shapes (形状). Some were as small as chickens, while some were about 90 feet long.
There were also terrible fights between dinosaurs. They might have happened more than 100 million years ago. Though there was no man to see any of the fights, we can be told by the footprints (足迹) that fights did take place.
1. According to the passage, dinosaurs did exist only________on the earth.| A．for millions of years |
| B．millions of years ago |
| C．more than 100 million years ago |
| D．when it was warm and wet somewhere |
| A．there were too many dinosaurs |
| B．parts of the earth became warm and wet |
| C．there were many green forests |
| D．they couldn’t find enough to eat |
| A．scientists are trying to make some dinosaurs |
| B．dinosaurs are dangerous enough |
| C．dinosaurs are worth studying further |
| D．scientists know nothing about dinosaurs |
| A．footprints | B．imagination | C．rocks and forests | D．dinosaurs’ eggs |
【推荐3】To discover whether bees can see colors, the following experiment is set up. A table is put in a garden and on the table is a piece of blue cardboard (硬纸板) with a drop of syrup (糖浆) on it. After a short time, bees come to the syrup. The bees then fly to their hive (蜂窝) and give the syrup to other bees in the hive. Then they return to the feeding-place which they have discovered. After a while, the blue cardboard with the syrup on it is taken away. Instead of this card, a blue card is now put on the left side of the first feeding-place and a red card to its right. These new card have no syrup on them. Thus, the blue card is on the left, the red card on the right, and there is nothing where the first blue feeding-card used to be. Very soon bees arrive again, and fly straight to the blue card. None to the red card.
1. To do the experiment, altogether how many cards do you need to prepare?| A．Two, one blue and one red. | B．Three, two blue and one red. |
| C．Three, one blue and two red. | D．Four, two blue and two red. |
A． | B． | C． | D． |
| A．the original blue card with syrup on it |
| B．the new blue card with no syrup on it |
| C．the empty space where original blue card was |
| D．the new blue card with syrup on it |
| A．cannot see colors | B．can see colors |
| C．cannot see blue | D．cannot see red |
【推荐1】Today’s grandparents are joining grandchildren on social media, but the different generation’s online habits couldn’t be more different. The over-55s are joining Facebook in increasing numbers, meaning that they will soon be the site’s second biggest user group, with 3.5 million users aged 55-64 and 2.9 million over-65s.
Sheila, aged 59, says, “I joined to see what my grandchildren are doing, as my daughter posts videos and photos of them. It’s a much better way to see what they’re doing than waiting for letters and photos in the post. I think I’m lucky I get to see so much more of their lives than my grandparents did.”
However, Sheila’s grandchildren are less likely to use Facebook themselves. Children under 17 are leaving the site — only 2.2 million users are under 17 — but they’re not going far from their smartphones. Chloe, age 15, even sleeps with her phone. “It’s my alarm clock so I have to,” she says. “I look at it before I go to sleep and as soon as I wake up.”
Teenagers might have their parents to thank for their smartphone and social media addiction as their parents were the early users of the smartphone. Peter, 38 and father of two teenagers, reports that he used to be on his phone or laptop constantly. He says, “How could I tell my kids to get off their phones if I was always in front of a screen myself?” So, in the evenings and at weekends, he takes his SIM card out of his smartphone and puts it into an old-style mobile phone that can only make calls and send text messages. “I’m not completely separated from the world, but the important thing is that I’m setting a better example to my kids and spending more quality time with them.”
Is it only a matter of time until the generation above and below Peter catches up with the new trend (趋势) for a less digital life?
1. Why does Peter take his SIM card out of his smartphone?| A．To stop his work. | B．To make calls to his boss. |
| C．To catch up with the new trend. | D．To set a good example to his kids. |
| A．Different. | B．Protected. | C．Cut off. | D．Figured out. |
| A．Children under 17 don’t use smartphone at all. |
| B．Chloe is one of the early users of the smartphone. |
| C．People may enjoy a less digital life in the near future. |
| D．Today’s grandparents enjoy a life without social media. |
Travel in the Everglades is difficult. You cannot walk through shallow water because the sawgrass will cut you. The water is too shallow for regular boats. So, we use an airboat. An airboat is a flat, open boat. Like an airplane, it has a big propeller to move it. The propeller is fixed on the rear of the boat. It makes a tremendous noise, but it does the job. The boat skims along the water’s surface. Although we can still get lost in an airboat, at least we are above the alligators(短吻鳄).
While hundreds of different kinds of animals live in the Everglades, the most famous is surely the alligator. Once endangered, alligators are now protected within Everglades National Park. Visitors are likely to see them both on land and in water.
For a long time, dangers have threatened the Everglades. Around 1900, some people felt this precious wetland should be drained (排干). They said it was just a big swamp and not good for anything. In the 1920s, there was a land boom in Florida. People wanted to build homes everywhere, including in the Everglades. They built canals, levees (防洪堤), and other water systems that stopped the rivers flowing into the Everglades. Factories were built near rivers that flowed into the wetland. These factories dumped poisonous waste that damaged the Everglades ecosystem.
People are now working to preserve the Everglades National Park for the future. Right now, one big problem is the paperbark tree. This tree is an invader from Australia.
Paperbark trees soak up a lot of water. In the early 1900s, people brought them to Florida because they thought they would help drain the Everglades. However, the invaders adapted too well. Paperbark trees have taken over hundreds of thousands of acres of the Everglades and killed other trees. Scientists are cutting down these invaders or spraying them with herbicides (除草剂) to kill them.
1. Which helps to explain why it is difficult to travel in Everglades?
| A．Airboats may make a very big noise. |
| B．You may get lost when passing through. |
| C．Paperbark trees soak up too much water there. |
| D．Many different kinds of animals are to be protected. |
| A．They have big propellers to move them faster than alligators. |
| B．The propeller makes loud noise so as to scare alligators. |
| C．Their flat bottom can skim along the water surface. |
| D．They can watch alligators without hurting them. |
| A．built canals and levees to stop the rivers flowing into Everglades |
| B．built factories near rivers that flowed into the wetland |
| C．brought Paperbark to soak up water in Everglades |
| D．are cutting down these Paperbark trees |
| A．that moves in from another place |
| B．that enters and takes control |
| C．that has been brought in |
| D．that is in danger |
【推荐3】Who says inventions are only made by grown-ups and professionals? Over the years, children have also succeeded in making their useful contributions to the world. Here are a few inventions that came to life from the minds of young children.
Hero Helmet
Seven-year-old Samuel Meyer’s invention is aimed at stopping people from riding their bikes or skateboards without using a helmet. The Hero Helmet features an inbuilt remote that controls a lock on the wheels which unlocks when the Helmet is being worn by the rider. Samuel says: no helmet, no bike.
Robotic Earthworm
The first thought that comes to mind is, why a robotic earthworm? Well, ten-year-old David Cohen had some useful applications in mind. He believed it could be used to find victims after a flood, earthquake or fire. The robot could get into small and dangerous places where search dogs and humans could not go.
B. E. A. C. O. N.
Fifteen-year-old Hannah Herbst’s invention, which stands for Bringing Electricity Access to Countries through Ocean Energy, was inspired by her pen pal who lives in Ethiopia and did not have access to lights. So she came up with B. E. A. C. O. N, which absorbs energy directly from ocean waves. Her invention won the “Discovery Education 3M Young Scientist Challenge” in 2015 and other numerous awards.
Portable Wheelchair Controller
At only eight years old, Amelia Fox created the invention to help lift people in and out of their wheelchair. This invention was not just born out of the desire to create something. Amelia developed this controller for her brother, who had just got hip surgery and needed the wheelchair to move around.
1. Who is the youngest inventor?| A．Samuel Meyer. | B．David Cohen. |
| C．Amelia Fox. | D．Hannah Herbst. |
| A．Hero Helmet | B．B. E. A. C. O. N. |
| C．Robotic Earthworm. | D．Portable Wheelchair Controller. |
| A．To give her brother assistance. | B．To benefit the earthquake victims. |
| C．To generate electricity effectively. | D．To protect bike riders from injuries. |
