为了那一抹深秋的红色，枫树可谓是耗尽了这一年所有的能量它们本该可以像那些夏绿秋黄冬秃的植物那样好好地在冷冷的秋冬日子里休个长假的，接下来我们就来聊聊关于英语作业花的颜色?以下内容大家不妨参考一二希望能帮到您!
英语作业花的颜色
为了那一抹深秋的红色，枫树可谓是耗尽了这一年所有的能量。它们本该可以像那些夏绿秋黄冬秃的植物那样好好地在冷冷的秋冬日子里休个长假的。
你们知道叶子的红黄绿色是怎么回事吗？
植物叶片的主要作用是通过光合作用（photosynthesis)获得树木生长所需要的糖分，碳水化合物等养料。作为叶片进行光合作用的场所，叶绿体中不但含有使叶片呈现绿色的叶绿素（chlorophyll ）而且还含有可以让叶片呈现黄色的类胡萝卜素（carotenoids)。夏日里，叶片中叶绿素含量高，所以鲜亮的绿色盖过了黄色。随着气温的下降和白昼时间变短，叶绿素被大量分解掉，这时，淹没在树叶里的类胡萝卜素等其他色素就会显露出来。
那么叶片的红色是怎么回事呢？使叶片呈现红色主要靠花青素（anthocyanin），普遍存在于液泡内的细胞液中。当细胞液为碱性时，花青素呈蓝紫色，当细胞液呈酸性时，花青素呈红色。入秋后枫叶内的花青素增多，而气温的下降又使叶绿素破坏消失，因此绿叶变成了红叶。
A final touch of color
Leaves turned the most amazing colors of orange and red and yellow in autumn. Scientists understand why summer leaves are green and why they change to yellow or orange in the autumn. But autumn reds are different. Some leaves turn red. Others don’t. But for most plants, the red color, anthocyanin, has not been hiding.
Actually，trees use up a lot of energy to make anthocyanin. So it has always been a mystery why they would go to all of that trouble at a time when they should be “going to sleep” for the winter. Trees that don’t make anthocyanins seem to naturally live in places with lots of “food”. Scientists suspect the anthocyanins may lie in the soil after the leaves drop, fertilizing the tree in the spring. The mystery isn’t solved yet, but scientists are a few steps closer!
