1 . If you’ve seen the movie Cast Away, you probably remember the scene in which Tom Hanks’ character, who survived a plane crash and found a refuge on a desert island, struggles to crack open coconuts before finally figuring out how to make use of one and drink from it. Well, it turns out that, in such a situation, a coconut palm tree actually could be your best hope for survival.
The coconut palm tree is native to tropical islands in the western Pacific Ocean. It is a tall tree, growing as tall as 100 feet, and with a branchless, light gray trunk that’s swollen at the base and topped by a crown of arching green leaves that stretch as long as 20 feet. It has fragrant (芳香的) yellow flowers, which appear in groups, and of course coconuts, which technically are a fruit rather than a nut, grow up to 14 inches long.
The fruit has a wooden shell surrounded by a fibrous cover, but inside is the stuff that a person wants — the coconut meat, which can be eaten raw or cooked, and the drinkable liquid. The nutritional qualities of a coconut — its meat and its juice — are nothing short of miracles. The meat is high in health fats, which are very important for survival, and the juice is filled with minerals like copper, iron and zinc, and can keep your electrolytes (电解质) balanced and blood levels healthy.
In Hawaii, coconut palm trees are known as “niu”, and are considered as a very important food source. While they are not native to this place, they are one of the famous “canoe plants”. Some of the ancestors of the trees currently found in Hawaii also moved slowly on water to or on the shore, alive for up four months at sea, still able to germinate (发芽). They are the symbol of vitality. They are admired here so much that traditionally, a coconut palm tree is planted at the birth time of a child born in Hawaii.
1. Why does the author speak of the movie Cast Away in Para.1?| A．To explain the way to prevent a terrible situation. |
| B．To introduce the theme of the movie. |
| C．To lead in the topic of the text. |
| D．To show Tom Hank’s success. |
| A．The trunk of the tree is swollen at the top. |
| B．The tree can grow tall and has no branches. |
| C．Yellow flowers appear in groups without any smell. |
| D．Coconuts are a kind of nut instead of a kind of fruit. |
| A．It has a unique taste. | B．Its price is quite high. |
| C．It can help people remain healthy. | D．Its production is increasing. |
| A．They decorate their houses with green leaves of coconut trees. |
| B．They drink the liquid inside coconuts. |
| C．They have a taste of coconut meat. |
| D．They plant a coconut plum tree. |
2 . Common water plant could provide a green energy source. Scientists have figured out how to get large amounts of oil from duckweed, one of nature’s fastest-growing water plants. Transferring such plant oil into biodiesel (生物柴油) for transportation and heating could be a big part of a more sustainable future.
For a new study, researchers genetically engineered duckweed plants to produce seven times more oil per acre than soybeans. John Shanklin, a biochemist says further research could double the engineered duckweed’s oil output in the next few years.
Unlike fossil fuels, which form underground, biofuels can be refreshed faster than they are used. Fuels made from new and used vegetable oils, animal fat and seaweed can have a lower carbon footprint than fossil fuels do, but there has been a recent negative view against them. This is partly because so many crops now go into energy production rather than food; biofuels take up more than 100 million acres of the world’s agricultural land.
Duckweed, common on every continent but Antarctica, is among the world’s most productive plants, and the researchers suggest it could be a game-changing renewable energy source for three key reasons. First, it grows readily in water, so it wouldn’t compete with food crops for agricultural land. Second, duckweed can grow fast in agricultural pollution released into the water. Third, Shanklin and his team found a way to avoid a major biotechnological barrier: For the new study, Shanklin says, the researchers added an oil-producing gene, “turning it on like a light switch”by introducing a particular molecule (分子) only when the plant had finished growing. Shanklin says, “If it replicates (复制) in other species-and there’s no reason to think that it would not — this can solve one of our biggest issues, which is how we can make more oil in more plants without negatively affecting growth.”
To expand production to industrial levels, scientists will need to design and produce large-scale bases for growing engineered plants and obtaining oil — a challenge, Shanklin says, because duckweed is a non-mainstream crop without much existing infrastructure (基础设施).
1. What can people get from duckweed firsthand?| A．Plant oil. | B．Stable biodiesel. |
| C．Sustainable water. | D．Natural heat. |
| A．Options for renewable energy. |
| B．Reasons for engineering genes. |
| C．The potential of revolutionary energy source. |
| D．The approach to avoiding agricultural pollution. |
| A．Industrial levels. | B．Unique design. |
| C．Academic research. | D．Basic facilities. |
| A．Duckweed Power | B．Duckweed Production |
| C．Genetic Engineering | D．Genetic Testing |
3 . Seagrass meadows(海草床) are wonder plants growing beneath the sea. They feed and shelter sea life and are masterful at storing carbon. Thanks to the assistance of tiger sharks, a huge seagrass meadow in the Bahamas Banks was recently discovered, offering the world a tool to fight climate change.
Seagrass has usually been detected by Earth-orbiting satellites that identify darker patches in the blue water. In this study, tiger sharks were selected as research tools due to their highly consistent associations with seagrass ecosystems. They spend 70% of their time in seagrass meadows. The team equipped eight tiger sharks with satellite tags (电子跟踪器), seven sharks with camera tags, and used a 360-degree camera on a shark for the first time ever.
The data researchers collected was astonishing. The world’s largest seagrass ecosystem, measuring at least 66,900 square kilometers, has been discovered. This reflects a 41% increase from previous estimates of global seagrass. Seagrass can capture (捕获) huge quantities of carbon by photosynthesis (光合作用) and stores it on the seafloor. In terms of climate change, this is excellent news; seagrass is 35 times faster a removing carbon than tropical rainforests. When referred to global seagrass carbon stock estimates, the study indicates that seagrass in the Bahamas may contain 19.2% to 26.3% of all the carbon stored in seagrass meadows on Earth.
Yet seagrass meadows are rapidly disappearing, with over 92% of meadows in the UK gone, according to the World Wildlife Fund. Scientists are collecting seeds and trying to grow new seagrass meadows through restoration projects. This new discovery offers optimism and proves the importance of the ocean for healing.
The sharks led us to the seagrass ecosystem in the Bahamas, which we now know is likely the most significant blue carbon sink(蓝色碳汇) on the planet. What this discovery shows us is that ocean exploration and research are essential for a healthy future. The untapped potential of the ocean is limitless. These meadows can be protected and can be replicated (复制,仿制), offering hope for climate change around the globe.
1. Why were tiger sharks chosen as research tools?| A．They are more flexible than other sea animals. |
| B．They can quickly adjust themselves to the deep sea. |
| C．They have a strong connection with seagrass ecosystems. |
| D．They can be easily equipped with experimental devices. |
| A．The decline of global seagrass meadows. |
| B．The impact of climate change on sea life. |
| C．The rapid increase in the amount of carbon on Earth. |
| D．The potential value of the world’s largest seagrass ecosystem. |
| A．Planting more seagrass meadows. |
| B．Developing new technology to collect seeds. |
| C．Mapping the distribution of seagrass meadows. |
| D．Encouraging people to join in restoration projects. |
| A．The New Way of Removing Carbon |
| B．The Significance of Ocean Exploration |
| C．A New Discovery: World’s Largest Seagrass Meadow |
| D．Tiger Sharks: Scientists’ Essential Helper to Study Climate |
