Polar body in animal meiosis and polar nucleus in plant meiosis are different concepts. Strictly speaking, polar nuclei are not produced during meiosis. In the process of plant germ cells, megaspore mother cells undergo meiosis to form four microspore mother cells, and these four cells undergo mitosis to form eight cells. After a series of transformation and degeneration, two polar nuclei and an egg cell are formed. During fertilization, an egg cell is combined with a sperm cell.

Therefore, polar nuclei are produced indirectly by meiosis and directly by mitosis.

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