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当春天悄悄来临时,你可曾想到那碧绿的青草和那万绿丛中的鲜花,是怎样开始它的生机的吗? 原来,在植物每个芽的顶端,都有一个半圆球形晶莹透亮的生长点,也叫做生长锥(图1、2)。春天,随着气温逐渐升高,植物的生长点也随之从沉沉的冬眠中甦醒过来。生长点是由一团具有很强分化能力的细胞组成,它是由种子胚的分生组织保留下来,继续行使分化机能的组织。根据植物遗传特性的不同,生长点就分化出各种植物自己所特有的叶形、枝形和花的样子。所以,当外界条件适合时,整个植物体也活跃起来,它们从土壤中吸取水份和营养。于
When the spring is quietly coming, have you ever thought of the green grass and the flowers in the green bushes, how did it begin its life? Originally, at the top of each bud of plants, there was a translucent spherical crystal Growth point, also known as the growth cone (Figure 1, 2). In spring, as the temperature gradually rises, plant growth points also wake up from the heavy hibernation. The growing point is composed of a group of cells with strong differentiation capacity, which is retained by the meristem of the seed embryo and continues to function as a differentiating tissue. According to the different genetic characteristics of plants, growing points on the differentiation of all kinds of plants own specific leaf shape, shape and flowers look. So when the external conditions are right, the whole plant is also active, drawing moisture and nutrients from the soil. in