Which of the following statements about seed plants is true Seeds are produced only by flowering plants (angiosperms) The sporophyte generation is more reduced in seed plants than in the ferns The gametophytes of seed plants are independent of the sporophytes All seed plant species are heterosporous The zygote of seed plants divides repeatedly to form the gametophyte

d. All seed plant species are heterosporous.

Explanation:

All the seed plants produce two types of spores. Therefore, seed plants are always heterosporous. The types of spores produced by these plants are microspore and megaspore. Microspore produces male gametophyte and serves to carry the male gametes while the megaspore gives rise to the female gametophyte. When the male gametes of a microspore fertilize a female gamete, the zygote is formed. The fertilized ovule is converted into a seed. Therefore, the formation of two types of spores is required for seed formation.

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