1 . It turns out our plants are just like us in some ways. We turn to medicines to relieve a minor flu or headache, and plants too have their ways of self-medicating. They protect themselves from environmental hazards like insects, drought and heat by producing salicylic acid (水杨酸). It is responsible for the anti-inflammatory action of aspirin, a drug which has been used by humans for centuries to counter pain and inflammation.

Researchers have found that plants’ salicylic acid, which is produced in chloroplasts (叶绿体), is usually generated in response to the stress caused by climate change. “It’s like plants use a painkiller for aches and pains, just like we do,” said plant biologist Wilhelmina van de ven from the University of California, River-side (U. C. R)

“We’d like to be able to use the finding to improve crop resistance (作物抗性),” said U. C. R.plant geneticist Jin-Zheng Wang. “That will be crucial for the food supply in our increasingly hot, bright world.”

Human skin produces ROS (Reactive oxygen species) (活性氧) in the absence of sunscreen. This causes freckles and burns. Similarly, environmental stresses result in the formation of ROS in plants which, at high levels, can cause death.

At low levels, however, ROS serves an essential function in plant cells. “ROS is a double-edged sword,” said Wang. “At non-lethal levels, ROS are like an emergency call to action, enabling the production of protective hormones ( 激素) such as salicylic acid.” The acid then acts to protect the plants’ chloroplasts, known to be the site of photosynthesis.

“With climate change, things like salicylic acid:   helping plants stand up to stresses have become more common. So, being able to increase plants’ ability to produce it represents a step forward in challenging the impacts of climate change on everyday life,” said Katayoon Dehesh, UCR professor of molecular biochemistry.

“Those impacts go beyond our food. Plants being in trouble are a sign of what the future holds for us,”   she continued. “Plants clean our air by removing the carbon dioxide from it while also offering us shade, and providing habitats for numerous animals. For humankind,   the benefits of boosting plants’ ability to survive are becoming increasingly essential.”

1. What is the main function of salicylic acid in plants?

A．To secure plants.	B．To produce chloroplasts.
C．To relieve pain and inflammation.	D．To generate hormones.

2. What is the main cause of ROS formation in plants?

A．Lack of sunscreen.	B．Chloroplastic acid.
C．Environmental stresses.	D．Use of Photosynthesis.

3. What is the main goal of the researchers at UCR?

A．To explore the history and significance of aspirin in human medicine.

B．To invent a device that can make plants do self-medicating.

C．To compare the differences between plants and humans in self-medicating.

D．To improve crop resistance by increasing plants’ ability to produce salicylic acid.

4. What is the text mainly about?

A．Plants can be improved to resist environmental hazards.

B．Plants produce their own aspirin to cope with stress.

C．Plants and humans share some common features and needs.

D．Plants contribute to the well-being of humans and animals.