动物是通过由其基因决定的固定方式生长的。甚至在它们很小的时候就能很容易地看到它们成长成熟后的模样。植物则不尽然,它们的生长也由基因决定着,但是最终的形态却由它们生长的环境所决定。例如,一棵生长在开阔地带的树木,可以生长得很高大宽 Animals are grown in a fixed way, determined by their genes. Even when they are young they can easily see how they have matured. Plants are not always the case. Their growth is also genetically determined, but the final form is determined by the environment in which they grow. For example, a tree that grows in an open area can grow tall and wide