大豆、棉花、小麦等农作物,都属于被子植物。它们的种子,播种以后形成幼苗、植株,经过开花传粉又重新产生种子,这种由种子开始又重新产生种子的过程称作被子植物的生活史。这里,我们着重介绍性器官及传粉、受精、产生种子的过程。1.花的结构 Soybeans, cotton, wheat and other crops are all angiosperms. Their seeds, which form seedlings and plants after sowing, are pollinated and regenerated after flowering. This process of starting and regenerating seeds from seed is called the life history of angiosperms. Here, we focus on sexual organs and pollination, fertilization, the process of producing seeds. The structure of the flower