Answer to Question #120915 in English for Nontobeko

Question

Describe the life cycle of plants

Answer 1

The life cycle of plants consists of a diploid generation (sporophyte) and a haploid generation (gametophyte). In higher plants, both the gametophyte and sporophyte are represented in the life cycle. In mosses, haploid prevails. The organs of sexual reproduction are formed on them haploid green plants. In particular, antheridia (male organs) form numerous spermatozoa while archegonia (female organs) produce one egg. After fertilization, the gametes give rise to the diploid stage, which develops directly on the haploid stage. The main life stage in vascular plants (plunders, horsetails, ferns, seeds) is diploid. On the leaves of ferns or in special structures, horsetails and crowns form sporangia in which small unicellular spores form as a result of meiosis. Scattered and falling into suitable conditions, they give rise to the haploid stage. Intermedia and archegonia are formed on the sprouts, gametes are produced, fertilization occurs, and a diploid plant develops from the zygote. In seed plants, an independent haploid stage does not exist. It is represented by groups of cells developing in special organs of diploid parent organisms. Sometimes, only a male gametophyte separately exists in the form of pollen grains, but no noticeable vital processes occur in it at that time. The female gametophyte of gymnosperms is the primary endosperm. In flowering plants, the reduced female gametophyte is the germinal sac. After fertilization, a new diploid organism that has developed from the zygote undergoes the first stages of development also under the protection of the maternal tissues.