Saturday, January 14, 2012

How do Moss , stag horn fern , mushroom , and bracket fungug reproduce ?

I think is fungi , but i don't know how they reproduce .

How do Moss , stag horn fern , mushroom , and bracket fungug reproduce ?
Not only you but many people , especially before the advent of microscopes , did not know how do they reproduce.!!!



This is because all these plants do not produce flowers and to that extent the process of reproduction is invisible .



Scientists had put them in a single category CRYPTOGAMS



meaning the union of gametes is not understood or HIDDEN ( Cryptos == hidden ; Gamos = gametes ). Even now the term is recognized!!



Now let us take the examples one by one ( all are microscopic views in the links below )=



1 ) Moss = It is cryptogam and a bryophyte . There is a regular Sexual Reproduction by production of Male and female gametes .



Antheridia = Male gametes are produced here in it . Click the link for a good photo =

http://www.stolaf.edu/people/ceumb/bio25...



Archegonia = Female gamete is produced ; male gamete is received during fertilization=

single dark body at the base in a white cavity is the female gamete =

http://www.biology.ualberta.ca/courses/b...



2 ) Stag horn fern==

This fern produces spores and these spores give rise to prothallus .



This prothallus also shows antheridia and archegonia and after fertilization develops a new plant ==



http://phobos.ramapo.edu/~spetro/Slides/...



http://web.gccaz.edu/~lsola/NonFlwr/thal...



3)Mushrooms and bracket fungi also show sexual reproduction followed by spore formation ( called Basidiospores ) these spores spread far and wide and produce new organisms of their kind !!

http://www.tolweb.org/tree/ToLimages/hil...



good text on the link below ==

http://io.uwinnipeg.ca/~simmons/lb2pg07....



Thank you ! bye !!
Reply:i believe they shoot out spores
Reply:These are all spore producing organisms, even though they may not be closely related.
Reply:Bryophyta (mosses) undergo an alternation of generations; The haploid gametophyte produces haploid gametes in multicellular gametangia by mitosis. Female gametangia are called archegonium and produce eggs, while male structures called antheridium produce sperm. Water is required so that the sperm can swim to the archegonium, where the eggs are fertilized to form the diploid zygote. The zygote develops into a sporophyte which grows out of the gametophyte and parasitizes it. Mature sporophytes produce haploid spores by meiosis in sporangia (hence sporic meiosis, a diplobiontic form of reproduction). When a spore germinates, it grows into another gametophyte."



Ferns reproduce via an alternation of generations. The conspicuous plant observed in the field is the diploid sporophyte. This plant creates by meiosis single-celled haploid spores which live in structures under the leaves of the fronds and which are shed and dispersed by the wind (or in some cases, by floating on water). If conditions are right, a spore will germinate and grow into a rather inconspicuous haploid plant body, a gametophyte called a prothallus. The haploid prothallus does not resemble the sporophyte, and as such ferns and their allies have a heteromorphic alternation of generations. The prothallus is short-lived, but carries out sexual reproduction, producing the diploid zygote that then grows out of the prothallus as the sporophyte. and into a familiar fern plant with fronds



Mushrooms are basidiocarps Sexual reproduction in basidiomycetes occurs when haploid hyphae fuse to produce a dikaryotic mycelium. When gametes fuse to form a diploid zygote, it immediately undergoes reduction division (zygotic meiosis) to form a haploid embryo which becomes a mycelium and which then produces a mushroom (basidiocaro) in which club-like structures known as basidia generate haploid basidiospores. A basidiospore is a reproductive spore produced by a mushroom. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia. When basidiospores encounter a favorable substrate, they may germinate, typically by forming hyphae. These hyphae grow outward from the original spore, forming an expanding circle of mycelium. Some basidiospores germinate repetitively by forming small spores instead of hyphae.



A bracket fungus is also a basidiomycetes, and the plan is similar, except the fruitng body, the basidiocarp, is a shelflike or bracket like structure often growing on a tree


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