What is the diploid phase in the life cycle of plants?
Embryonic development is seen only in the diploid generation. The embryo, however, is produced by the fusion of gametes, which are formed only by the haploid generation. So understanding the relationship between the two generations is important in the study of plant development.
The plant life cycle alternates between haploid and diploid generations. Embryonic development is seen only in the diploid generation. The embryo, however, is produced by the fusion of gametes, which are formed only by the haploid generation.
Fertilization gives rise to a multicellular diploid sporophyte, which produces haploid spores via meiosis. This type of life cycle is called a haplodiplontic life cycle (Figure 20.1). It differs from our own diplontic life cycle, in which only the gametes are in the haploid state.
The life cycle of seedless, vascular land plants involves altering generation. The diploid sporophyte stage alternates with the haploid gametophyte stage. While the diploid phase is the dominant phase in their life cycle, the haploid phase is inconspicuous.
Diploid-dominant life cycle Early in the development of an animal embryo, special diploid cells, called germ cells, are made in the gonads (testes and ovaries). Germ cells can divide by mitosis to make more germ cells, but some of them undergo meiosis, making haploid gametes (sperm and egg cells).
The large and familiar phase of ferns is the sporophyte. It is the diploid phase. The sporophyte has vascular tissue, and can conduct water from the soil to other parts of the plant. The sporophyte produces haploid spores by meiosis.
The sexual phase, called the gametophyte generation, produces gametes, or sex cells, and the asexual phase, or sporophyte generation, produces spores asexually. In terms of chromosomes, the gametophyte is haploid (has a single set of chromosomes), and the sporophyte is diploid (has a double set).
Organisms with a diploid life cycle spend the majority of their lives as diploid adults. When they are ready to reproduce, they undergo meiosis and produce haploid gametes. Gametes then unite in fertilization and form a diploid zygote, which immediately enters G1 of the cell cycle. Next, the zygote’s DNA is replicated.
Diploid describes a cell or nucleus which contains two copies of genetic material, or a complete set of chromosomes, paired with their homologs (chromosome carrying the same information from the other parent). Other organisms cycle between diploid and haploid lifecycles. …
Plants have two distinct stages in their lifecycle: the gametophyte stage and the sporophyte stage. The haploid gametophyte produces the male and female gametes by mitosis in distinct multicellular structures. Fusion of the male and females gametes forms the diploid zygote, which develops into the sporophyte.