1. What makes potted roses easier to plant?
| A．Lower nutrition requirement. |
| B．Stronger cold resistance. |
| C．Better root development. |
| A．They need less soil. |
| B．They are easier to transport. |
| C．Their planting time is fixed. |
| A．Damp condition. | B．Heavy sunshine. | C．Continuous watering. |
| A．Types of roses. | B．Ways of rose packing. | C．Tips on rose growing. |
2 . The rapid pace of global warming and its effects on habitats raise the question of whether species are able to keep up so that they remain in suitable living conditions. Some animals can move fast to adjust to a swiftly changing climate. Plants, being less mobile, rely on means such as seed dispersal(传播) by animals, wind or water to move to new areas, but this redistribution typically occurs within one kilometre of the original plant.
When the climate in a plant’s usual range becomes hotter than it can tolerate, it must find new, cooler areas that might lie many kilometres away. One explanation for long-distance seed dispersal is through transport by migratory (迁徙的) birds. Such birds swallow seeds when eating fruit and can move them tens or hundreds of kilometres outside the range of a plant species.
Gonzáiez-Vary and colleagues report how plants might be able to keep pace with rapid climate change with the help of migratory birds. The authors analysed the fruiting times of plants, patterns of bird migration and the interactions between fruit-eating birds and fleshy-fruited plants across Europe. Plants with fleshy fruits were chosen for this study because most of their seed transport is by migratory birds, and because fleshy-fruited plants are an important part of the woody-plant community in Europe. The common approach until now has been to predict plant dispersal using models fitted to abiotic (非生物的) factors such as the current climate. Gonzáiez-Vary instead analysed an impressive data set of 949 different seed-dispersal interactions between bird and plant communities, together with data on entire fruiting times and migratory patterns of birds across Europe. The researchers also analysed DNA traces from bird wastes to identify the plants and birds responsible for seed dispersal.
1. How do species adapt to climate changes when it’s too hot?| A．All animals will move away across great distanced. |
| B．Some plants depend on migratory birds to carry seeds. |
| C．Some plants depend on animals, wind or water to move. |
| D．Plants’ seeds disperse to cooler places of several kilometres away. |
| A．Most of these can’t fit rapid climate change |
| B．Migratory birds like making nests in them |
| C．Migratory birds transport their seeds. |
| D．They are favoured by most birds. |
| A．To explain relations between fruit plants and migratory birds. |
| B．To clarify the reason why birds migrate in fruiting times. |
| C．To present a fact that migratory bird eats flesh fruits. |
| D．To show that fruits depend on migratory birds. |
| A．The advantage of fruit plants. |
| B．The destination of the bird migration. |
| C．The adaptation of fruit plants to the climate change. |
| D．The influence of climate change on plants and animals. |
3 . Scientists have discovered how plants manage to live alongside each other in places that are dark and shady. Plants in the deep darkness of a thick forest, where natural supplies are not very great in amount, won’t attempt to top their neighbors in growth as those in moderate (中度的) shade do. In deep shade conditions, it would be a waste of energy and harmful to survival because green shoots would never be able to top their larger neighbors in growth.
So how do plants prevent such growth in deep shade conditions? The secret lies in the clocks insides them, say scientists from the John Ines Centre and the University of Bristol.
They have discovered that when plants notice deep shade, this changes the expression of genes parts of the circadian clock (昼夜节律时钟) — the inner daily timer found in plants and other things. These clock parts perform an additional role in preventing plants from lengthening and overtopping neighbors.
The work identifies a previously unknown role of the circadian clock in controlling plant development and the findings may have possible effects on both natural plant populations and crops. Professor Antony Dodd of the John Innes Centre said, “The biological clock of plants plays a big part in their development and fitness. This work casts new light on a new role of the circadian clock in adapting plants to competition with other plants in their environments.” “It also gives us new insights into how plants adapt to very deep shade, where resources are very limited,” said Professor Kerry Franklin at the University of Bristol.
This work provides evidence for the firmness of the circadian clock in stressful environments, and information that may be useful in developing new generations of crops in a challenging climate.
1. What do plants normally do in moderate shade?| A．Struggle to preserve energy. | B．Compete for limited resources. |
| C．Try to outgrow their neighbors. | D．Depend on each other to survive. |
| A．By changing their gene expression. | B．By making them realize light change. |
| C．By helping them adapt to the darkness. | D．By controlling their growth in deep shade. |
| A．To share a new discovery about plants. | B．To introduce the role of the circadian clock. |
| C．To explain plants secret of living in forests. | D．To compare plants living in certain condition. |
| A．How plants face a challenging climate |
| B．Why plants respond to different shade levels |
| C．Why the circadian clock is vital to plants' growth |
| D．How plants become good neighbors in times of stress |
4 . Mutualism—win-win ecological partnerships perfected over evolutionary time-lengths—is a less-known ecological relationship that is also weak and easily hurt by the effect of a rapidly changing planet.
Bees and flowers are typical examples of mutualism. Some bee tongues are perfectly evolved to tap into certain flowers. By specializing in those plants, the longer-tongued bees reduce competition with insects that can't access those sweet foods.
That mutualistic relationship, however, has been impacted in at least one population of bees and flowers. As certain flowers in Colorado have become rarer due to warming temperatures, the tongues of the bumblebees（大黄蜂）that historically fed on them have become shorter.
Like many of their relatives, bumblebees are on the decline. To find out what's going on, a team of researchers headed to Colorado. The researchers examined bumblebee samples collected on three mountains from 1966 to 1980 and also gathered a fresh set, which they collected in the same places from 2012 to 2014. They performed the task of measuring all the historic and recently caught bees' tongues.
As the team reports in Science, both of the species tongues have declined in length over time. The team found a nearly 25-percent decrease in tongue length between the bees collected decades ago and those living in the same region today.
Next they turned to the flowers. Looking at contemporary and historic botanical data, the scientists confirmed that the number of flowers with short tubes did not increase in large quantities. They found that in response to warmer temperatures, flowers have been moving up the mountains and becoming rarer at lower altitudes. This altitude-climbing effect has ultimately resulted in an approximate loss of millions of flowers.
The findings paint a telling picture: hotter summers caused bumblebees' choice flower species to disappear, forcing them to evolve shorter tongues to tap into the remaining food sources. Then, competition with generalist species, more time and energy needed and a forced reliance on alternative sources all likely contributed to the bees' overall decline.
1. What was the cause of bumblebees' tongues shortening in Colorado?| A．Decrease of certain flowers. | B．Fight within populations. |
| C．The pollution of their food. | D．Common growth problems. |
| A．Clear results were published. | B．It was based on assumptions. |
| C．It was carried out for decades. | D．It intended to study bee diseases. |
| A．For more sunlight. | B．For cooler environment. |
| C．For more growing space. | D．For defence against insects. |
| A．A research on bees' tongues. | B．Facts and causes of bees' decline. |
| C．The relation of flowers and bees. | D．The climate influence on mutualism. |
5 . In 2010, Barack Obama was to pay a visit to Mumbai’s Gandhi Museum, where palm(棕榈)trees full of me dotted the grounds. The president knew me well-coconuts (椰子)are a part of life in Indonesia, where he spent his boyhood. Before his visit, Indian authorities, however, removed every last sign of me around the museum. They were afraid the president of the United States would be taken out by one of me falling on his head.
Let’s get this out of the way: My reputation as the “killer fruit” of countless innocents was then and still is a misbelief. A repeatedly misinterpreted 1984 study overstated the number of deaths I caused by hitting people on the head, and the word spread. Today, the only things about me “to die for” are the sometimes too-delicious foods you humans make with me, such as cookies and pies. A decade ago, health experts briefly gave me a halo because some of my fats may raise beneficial cholesterol (胆固醇). But ask a heart doctor today and they’ll tell you that coconut oil will raise your bad cholesterol as much. Death by coconut, indeed!
People have other wrong ideas about me. But allow me to leave you with a sweet presidential tale. A World War II boat commanded by one John F.Kennedy was destroyed in 1943 by a Japanese warship. Kennedy and his surviving crew were stuck on an island. They were suffering from hunger, thirst and injuries when they met two friendly native coast-watchers. Kennedy scratched a message into a coconut shell: “NAURO ISL...COMMANDER...11 ALIVE...NEED SMALL BOAT...KENNEDY.”
The coast-watchers delivered this successfully and all the crew were saved. Years later, the coconut shell was given to the newly elected president. It sat on his office desk throughout his presidency and now is a center-piece of the John F.Kennedy Library in Boston-as the proof that we coconuts don’t take lives, we save them.
1. Why did Indian officials get rid of “me”?| A．To reduce Obama’s fear. | B．To avoid unexpected injuries. |
| C．To show their welcome tradition. | D．To follow the request from the US. |
| A．thought little of me | B．did great damage to me |
| C．made me well-known | D．brought me a good name |
| A．Amusing. | B．Anxious. |
| C．Concerned. | D．Romantic. |
| A．To show a new discovery. | B．To correct people’s misbelief. |
| C．To tell the history of coconuts. | D．To describe a successful rescue. |
6 . Mangroves are trees that typically grow in saltwater along coasts. But some red mangroves end up deep in the rainforests of Mexico’s Yucatan Peninsula. These plants live in freshwater along the San Pedro Martir River. That’s nearly 200 kilometers from the sea. Scientists wanted to know how these mangroves got trapped so far inland. Carlos Burelo was among them. He became curious about these mangroves on a childhood fishing trip there 35 years ago. Burelo saw that the roots of the mangroves grew above ground. This was different from the other trees.
Burelo’s team first investigated where the freshwater mangroves came from. They started by collecting their leaves and then compared their DNA to the leaves from coastal mangroves which were growing along the Gulf of Mexico. The DNA helped identify the origins of the mangroves on the San Pedro Martir River. They had started along the Gulf of Mexico, some 170 kilometers away from the river. The team discovered other evidence that this ecosystem had once been coastal. They discovered 112 other species in this region that are typically found near coasts.
The researchers looked at the soil too. “These sediments (沉积物)near the mangroves revealed exactly what we expected,” says Exequiel Ezcurra, an ecologist at the University of California. In all, the researchers turned up coastal stones, shells of sea snails and clay sediments rich in shell fragments (碎片). These led the researchers to conclude the area used to be part of the ocean long ago.
Computer models of how sea level has changed over time confirmed those findings. The models showed that when sea levels were higher in the past, the oceanmerged withthe lower basin of the San Pedro Martir River. That would have been around 150,000 to 130,000 years ago. This pushed red mangroves and other species inland.
“This discovery highlights how changes to the past climate have affected the world’s coastlines,” Ezcurra says. “It also offers a chance to better understand how future sea level rise may affect these ecosystems.”
1. What did Burelo notice as a child?| A．The changes of the sea water. |
| B．The problems facing the rainforest. |
| C．The unusual roots of some mangroves. |
| D．The influence of mangroves on fishing. |
| A．They are close in DNA. | B．They have different leaves. |
| C．They have different origins. | D．They both have many species. |
| A．The composition of the soil is very complicated. |
| B．The freshwater mangroves once grew in the sea. |
| C．Sea creatures influence the growth of mangroves. |
| D．The sea level has little change over the past years. |
| A．Developed from. | B．Changed into. |
| C．Depended on. | D．Combined with. |
