Question

Are pteridophytes haplodiplontic?

Answer 1

For hundreds of millions of years before flowering plants, the landscape was dominated by plants that looked like ferns. Pteridophytes resemble their ancestors in many ways. Pteridophytes, unlike most other members of the Plant Kingdom, reproduce through spores rather than seeds.

Complete answer:
Pteridophyta is one of the Plant Kingdom's older plant families. Pteridophytes have the following general characteristics:
- They have no seeds.
- They have multiple cells.
- They reproduce by spores.
- They are self-contained, free-living organisms.
- They have a distinct plant body that is divided into root, stem, and leaves.

During the life cycle of some organisms, different "generations" of the species succeed each other. Plants and many algae have two multicellular stages, and the life cycle is known as generation alternation. The term "life history" is frequently used, especially for organisms such as red algae, which have three (or more) multicellular stages rather than two.

Both haploid and diploid stages are multicellular in the Haplodiplontic Life Cycle. In some, the gametophyte is the dominant and free-living phase, while the sporophyte is a small and short-lived phase that is dependent on gametophytes, such as Bryophytes. The sporophyte is the independent and free-living dominant stage in pteridophytes. It is replaced by a short-lived gametophyte. Some examples are Ulva, Polysiphonia, Ectocarpus, Kelps have a haplodiplontic life cycle.

Thus, pteridophytes are haplodiplontic.

Note: The zygote divides mitotically to produce a multicellular diploid sporophyte in sporadic meiosis (also known as intermediary meiosis). The sporophyte produces spores through meiosis, which then divides mitotically to produce haploid individuals known as gametophytes. Mitosis is the process by which gametophytes produce gametes. The gametophyte in some plants is not only small but also short-lived in other plants and many algae, the gametophyte is the "dominant" stage of the life cycle.