Bryophytes, a class of diplobionts plants, are represented by anthocera, liverworts and especially mosses. life cycle with alternation of heteromorphic generation, with a predominance of the gametophytic (haploid) phase over the sporophytic one (diploid). Meaning to say that the gamete-producing portion in these vegetables is more durable and independent, performing photosynthesis.
With a very small size and absence of sap conducting vessels, these vegetables evolve with extreme need for a humidified environment (high content of moisture), which not only favors their survival but also provides a means for the displacement of male gametes (flagellates), allowing reproduction sexual.
In some species of mosses, male and female reproductive structures can be found. together in the same plant or isolated in different plants, with gametophyte reaching 5 to 10 cm of height.
When mature, at the top of the gametophyte an organ develops that in the male plant is called antheridium, and in the female one called archegon. Inside the antheridium, the anterozoids (biflagellate gametes) are produced, and in the archegon, the oosphere.
Due to rain or dew concentration, the anterozoids move towards the archegon, thus fertilizing the oosphere. From then on, the sporophytic phase of the cycle begins, with a sporophyte appearing at the upper end of the female gametophyte. diploid whose apex has a capsule containing haploid spores in its interior, originating from meiosis (cell division reduction).
These spores, after being expelled from the capsule, are dispersed by water, wind or animals. Due to the latent capacity of metabolism, they are resistant to bad weather (heat and low moisture), germinating only when conditions are favorable, forming a new gametophyte, restarting the cycle.
By Krukemberghe Fonseca
Graduated in Biology
Source: Brazil School - https://brasilescola.uol.com.br/biologia/reproducao-uma-briofita.htm
