20、植物的雄配子是怎样产生的? 在花药四角的表皮内出现孢原细胞。由孢原细胞进行分裂,产生壁细胞和造孢细胞。在壁细胞分裂的同时,造孢细胞也进行分裂,形成很多花粉母细胞(或小孢子母细胞)。每个花粉母细胞(2n)经过减数分裂,产生四个染色体数目减半的子细胞,即四个小孢子(n),称之为四分体(或四分孢子)。不久,小孢子的胞壁加厚, 20, the plant’s male gamete is how to produce? In the anther four epidermal cells appear spores. Split by sporogenous cells, producing parietal cells and sporogenous cells. At the same time that the parietal cells divide, the sporogenous cells also divide to form many pollen mother cells (or microspore mother cells). Each pollen mother cell (2n) undergoes meiosis, resulting in four daughter cells in half the number of chromosomes, namely four microspores (n), called tetrad (or tetradospore). Soon, the microspore wall thickening,