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It's never a real problem for us when the weather gets cold. We can put on more clothes, stay next to a fire place or simply travel to a warmer city to spend the winter – people have many different ways of dealing with the cold.
But things are not as easy for plants. Unlike humans, plants can't move to run from the cold or produce heat to keep themselves warm. So how do they manage to live in the freezing winter?
Actually plants have their own ways too.
According to researcher Amy Zanne, the cold is a big challenge for plants. Their living tissues(活组织) can be hurt when they freeze. "It's like a plant's frostbite(冻疮)," Zanne told Science Daily. Also, the cold can cause air bubbles(气泡)to form in the plant's water system. "If enough of these air bubbles come together, they will be harmful to the plant," she explained.
To live through cold weather, plants have developed three ways, according to the study.
Some plants, such as oak trees, avoid frostbite by dropping their leaves before the winter comes, which can shut off the flow of water between roots and leaves, and they grow new leaves and water transport cells when the warm spring returns.
Other plants, pine trees for example, protect themselves by making their water transport cells thinner, which makes it easier for cells to travel among air bubbles.
The third strategy is also the most special – some plants die on the ground in winter and start growing as new plants from seeds(种子)when conditions get warmer.
However, the tudy also found that these smart ways were developed over a very long period of time. This causes scientists to worry that plants may not be able to deal with human – caused climate change(气候变化), which has only started recently.
Scientists are hoping that this study can help people find possible ways to save plants from the danger from climate change.