What is Endosporic gametophyte?
What is Endosporic gametophyte?
A gametophyte that develops within a spore. For example, the female gametophyte of Selaginella is contained within the megaspore and at maturity only a portion, bearing the archegonia, is exposed through the spore wall.
What is Exosporic development of embryo?
Endosporic development is a process that evolved before seed-bearing plant processes and is still used by different classes of organisms, for example, most ferns. Homosporous endosporic development is essentially the precursor to modern seed-bearing plants, which demonstrate heterosporous endosporic development.
What is Endosporic germination?
In endosporic germination, the spore protoplast divides within the spore wall, forming a multicellular structure. The protonema develops inside the stretched spore wall.
What is free living gametophyte?
The free living gametophyte means that has free existence and is not depended on sporophyte for food and other components. These spores germinate and produce gametophyte. The gametophytes bear male and female sex organs called antheridia and archegonia.
What is Endosporic development of female gametophyte?
Generally, three of the four megaspores degenerate. Within the cytoplasm of the surviving functional megaspore (endosporic development), a microscopic, multicellular megagametophyte (female gametophyte) develops by mitosis. One cell of this gametophyte phase will function as an egg.
What happens in bryophytes after spore germination?
In bryophytes, spore germination is initiated with swelling, resulted from water absorption by the spore; and distension, when the protonema formed ruptures the cell wall (Nehira 1983. Spore germination, protonema development and sporeling development.
Which group has no free living gametophyte?
gymnosperms
Complete answer:In gymnosperms (like Pinus), the male and female gametophyte do not have an independent free-living existence.
What is the female gametophyte in gymnosperms?
The female gametophyte of gymnosperms is a large and multicellular structure, and serves the double function of bearing the gametes as well as the nourishment of the developing embryo.
What is the most common type of female gametophyte with eight nuclei?
The Amborella-type female gametophyte is restricted to a single extant species, Amborella trichopoda, and at maturity consists of eight cells and nine nuclei. Development of the Amborella-type game- tophyte is essentially identical to the Polygonum-type except that there is an additional and asynchronous cell division …
What is the most common type of female gametophyte in flowering plants?
The most common and presumably ancestral type of female gametophyte in the angiosperms is one that develops from the chalazal haploid megaspore, the result of monosporic megasporogenesis.
What is the diff between endosporic and exosporics?
Login wht is diff between…exosporic and endosporic development? ENDOSPORIC : development of gametophyte within the spore as in seed plants EXOSPORIC : gametophte developed outside the spore wall e.g : free living multicellular gametophyte
How is gametophyte developed within the spore wall?
ENDOSPORIC : development of gametophyte within the spore as in seed plants EXOSPORIC : gametophte developed outside the spore wall e.g : free living multicellular gametophyte Exosporic germination takes place outside the sporangia in the soil it is found in pteridophytes where the gametophyte is independent
Where does exosporic germination take place in the sporangia?
Exosporic germination takes place outside the sporangia in the soil it is found in pteridophytes where the gametophyte is independent This discussion on wht is diff between…exosporic and endosporic development? is done on EduRev Study Group by NEET Students.
Are there any plants that produce only one type of spore?
Those vascular plants, such as clubmosses and many ferns, that produce only one type of spore are said to be homosporous. They have exosporic gametophytes — that is, the gametophyte is free-living and develops outside of the spore wall.