Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.

Harmer, a professor in the University of California at Davis, Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.

By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.

The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably tack the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.

When sunflowers track the sun, the east sides of their stems grew more rapidly than the west sides. At night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day or on the other side at night. A plant growth-regulating hormone (激素), called auxin, appears to be a key driver.

The “dance” to the sun cycle obviously slows when the sunflower matures (成熟) and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.

“Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.

“The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said “We’re currently testing this idea.”

1.Why did Harmer do the experiment on sunflowers?

A.To see how sunflowers grow up B.To show what sunflowers’ genes are.

C.To study why sunflowers track the sun. D.To check if sunflowers swing in cloudy days.

2.What does the underlined word “staking” probably mean in Paragraph 3?

A.breaking B.controlling C.growing D.searching

3.What is the result of sunflowers being stopped from moving?

A.They will produce a number of new genes. B.They will grow faster than usual.

C.They won’t swing back though set free. D.They won’t grow well.

IG, a Chinese esports club, won the world championship title in LOL (League of Legends) in 2018. It beat European team 3:0 in South Korea. It was the first time that a club from China’s LPL (League of Legends Pro League) won the title in the world championship’s eight-year history. So what is esports?

Esports (Electronic Sports) is a form of competition using video games between professional players. It is not only a simple game in a sense, but a sport in which players use electronic equipment to play against each other in intelligence. It can improve the players’ thinking ability, heart-to-eye coordination (协调), willpower and develop team spirit.

In 2003, esports became the 99th sport in China. However, esports is different from traditional sports and online games. Traditional sports athletes mainly train their physical ability and skills, such as muscle memory, exercising and dieting; while esports athletes’ training is mostly about the mind, such as studying strategies (策略) and new updates for the game.

The industry has been developed for more than 10 years, but the public usually hold the opinion that playing online games has no benefit but taking one’s attention away from their duties. In fact, there are several differences between esports and online games:

First, the basic features. Online games are entertainment games while esports is a sport. Esports is an intellectual competition between people in an organized environment created by information technology.

Second, the game rules. Esports has clear game rules. Its biggest feature is strict time and round limitations. However, online games are lack of clear rules of the game. Without time limit, it’s easy for people especially teenagers to be addicted to (沉迷于) it.

Third, the sports spirit. Esports competitions between athletes pay great attention to fair sports spirit. Some online games only need to recharge (充钱) to gain advantages, which is the main difference between esports and online games.

In the upcoming 2022 Asian Games to be held in Hangzhou, esports will officially become a medal event. Esports is a new sporting activity. It will take a long time to grow into a mature industry like NBA (the National Basketball Association of the US). Let’s have a better understanding of esports and expect its bright future.

1.Which club won the world championship title in LOL in 2018?

2.What is esports?

3.When did esports become the 99th sport in China?

4.What is esports athletes’ training about?

5.What is the passage mainly about?

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