What is soral evolution in Pteridophytes?
Sorus is a group of sporangia produced on the adaxial/abaxial surface of the sporophylls in ferns. Sporangia sometimes can be either scattered over the lower surface of leaf forming feet or forming marginal tassels on the surface of slender leaf division as seen in Osmunda.
What are sorus Pteridophytes?
sorus, plural sori, in botany, brownish or yellowish cluster of spore-producing structures (sporangia) usually located on the lower surface of fern leaves.
What is sorus stage?
The stages in progressive evolution of sori can be depicted as follows: (1) simple clusters of sporangia, these more or less coalesced (family Marattiaceae) or separate (Gleicheniaceae), all of them maturing at the same time, (2) gradate clusters of sporangia, the outermost ones maturing first, the innermost last, and …
What is Bisporangiate sorus?
: having two different kinds of sporangia — compare monoclinous.
What is the function of the sorus?
Sori are clusters of sporangia found only in ferns (singular: sorus). These are a product of sexual reproduction. The sporangia within the clusters each house several haploid spores. After release from the sporangium, these spores will generate and grow into the gametophytic generation under proper conditions.
What is the function of sporangium?
A sporangium is a structure in certain plants and other organisms that is charged with making and storing spores. Spores are haploid structures created in organisms that help to germinate and form new organisms. In other words, they help organisms to reproduce.
What is indusium Pteridophytes?
A flap of tissue that protects the sori in some ferns. This can take a variety of forms. When spores are mature and ready for release, the indusia usually shrivel or bend backwards to expose the sporangia. Occasionally, if the indusia completely cover the sporangia.
Who discovered Rhynia and from where?
Description. Rhynia gwynne-vaughanii was first described as a new species by Robert Kidston and William H. Lang in 1917. The species is known only from the Rhynie chert in Aberdeenshire, Scotland, where it grew in the vicinity of a silica-rich hot spring.
Is sorus a sporophyte or Gametophyte?
The sporophyte generation is photosynthetic and is independent of the gametophyte. The sporangia are protected by a layer of cells called the indusium. This entire structure is called a sorus.
What is the difference between sporangium and sporocarp?
As nouns the difference between sporocarp and sporangium is that sporocarp is the structure on a fungus which houses the spore-producing organs while sporangium is (botany|mycology) a case, capsule, or container in which spores are produced by an organism.
What is sporocarp and its role in propagation?
A sporocarp is a specialised type of structure in the aquatic ferns of the order Salviniales whose primary function is the production and release of spores.
What reproductive structures are produced in a sorus?
In Botany, Sorus, (sori in plural), is a yellow-brown cluster of structures that produce spores (sporangia).
How many types of protosteles are there in pteridophytes?
Ø There are FIVE types of protosteles in Pteridophytes, they are: (a) Haplostele, (b) Actinostele, (c) Plectostele, (d) Mixed protostele and (e) Mixed protostele with pith. (a). Haplostele Ø A protostele with a smooth core of xylem surrounded by uniform layers of phloem.
What is the vegetative plant body in a pteridophyte?
The vegetative plant body is a sporophyte in Pteridophytes. Sporophyte is differentiated into stem, leaves and roots. This spoi ophyte is an independent plant. The sporophyte of Pteridophyta possesses well-developed vascular tissue consisting of both xylem and phloem.
Are there any living Pteridophyta left on Earth?
Pteridophyta is a group of ancient plants. They formed the dominant part of the earths during Palaeozoic and Mesozoic periods. Majority of Pteridophytes became extinct. They are preserved in the form of fossils or coal deposits. Only a few living Pteridophyta are left.
When did most pteridophytes become extinct on Earth?
Occurrence and evolution of Pteridophytes Pteridophyta is a group of ancient plants. They formed the dominant part of the earths during Palaeozoic and Mesozoic periods. Majority of Pteridophytes became extinct. They are preserved in the form of fossils or coal deposits. Only a few living Pteridophyta are left.