初一《植物学》,在讲授绿色开花植物时,对这类植物的胚和胚乳的形成论述得较细,但在“裸子植物”一节课时在提出胚和胚乳的概念时,教材只是一提而过。在平时教学时,不少学生对此产生疑问,那么被子植物与裸子植物的胚和胚乳到底有什么不同?又有什么相同之处? 被子植物和裸子植物的种子里都有胚和胚乳,它们的胚都是由精细胞和卵细胞受精后发 In the first “Botany,” when teaching green flowering plants, the formation of embryos and endosperm of such plants was discussed in detail. However, when the concept of embryo and endosperm was proposed in the first lesson of “gymnosperm”, the textbook was only Since then. In the usual teaching, many students questioned whether the angiosperms and the embryos and endosperms of gymnosperms are different. What are the similarities? The seeds of angiosperms and gymnosperms contain embryos and endosperm. Embryos are made by sperm cells and oocytes after fertilization