What does archegonia mean in biology?
archegonium, the female reproductive organ in ferns and mosses. An archegonium also occurs in some gymnosperms, e.g., cycads and conifers. A flask-shaped structure, it consists of a neck, with one or more layers of cells, and a swollen base—the venter—which contains the egg.
What is the archegonium function?
The archegonium also serves as the site of fertilization. After the egg is fertilized, the egg will remain in the archegonium until it develops into a sporophyte. A sporophyte is the spore-producing form of the plant. The archegonium releases the sporophyte once it has fully developed.
What are produced in archegonia?
At maturity, archegonia each contain one egg, and antheridia produce many sperm cells. Because the egg is retained and fertilized within the archegonium, the early stages of the developing sporophyte are protected and nourished by the gametophytic tissue.
What is the difference between archegonia and archegonium?
As nouns the difference between archegonia and archegonium is that archegonia is while archegonium is (botany) a multicellular reproductive structure that contains a large, non-motile gamete (egg cell), and within which an embryo will develop.
What happens to the archegonium neck post fertilization?
After fertilization, the archegonium becomes modified into a protective sheath around the young sporophyte. There are significant differences, in both structure and development, between hornwort, liverwort and moss sporophytes.
Where are archegonia found?
Archegonia are typically located on the surface of the plant thallus, although in the hornworts they are embedded.
Which gymnosperms have no archegonia?
Gnetum.
How do Sporangias burst?
When the sporangia of Rhizopus bursts upon maturation, the spores spread out. So, with the help of different agents, the spores are transferred to various places and when they land on a particular surface, new organism (mycelium) starts growing.
What are Pteridophytes Sporophylls?
Pteridophytes are vascular plants. Leaves called sporophylls produce clusters of capsular structures called sporangia that bears spores which germinate and yield gametophytes. Hence they show alternation of generations, in which a sporophyte produces spores through meiosis and a gametophyte forms gametes by mitosis.
What is botany Antheridium?
An antheridium is a haploid structure or organ producing and containing male gametes (called antherozoids or sperm). The plural form is antheridia, and a structure containing one or more antheridia is called an androecium. Androecium is also the collective term for the stamens of flowering plants.