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The oocytes were fertilized in the archegonia by free-swimming flagellate sperm produced by windborne miniaturized male gametophytes in the form of pre-pollen. The resulting zygote developed into the next sporophyte generation while still retained within the pre- ovule , the single large female meiospore or megaspore contained in the modified ...
In the bryophytes the sporophyte remains dependent on the gametophyte, while in all other embryophytes the sporophyte generation is dominant and capable of independent existence. Embryophytes also differ from algae by having metamers. Metamers are repeated units of development, in which each unit derives from a single cell, but the resulting ...
The sporophyte produces free-swimming haploid spores by meiosis that germinate into haploid gametophytes. [ 7 ] However, in land plants , either the sporophyte or the gametophyte is very much reduced and is incapable of free living.
Phaeoceros is a genus of hornworts in the family Notothyladaceae.The genus is global in its distribution. Its name means 'yellow horn', and refers to the characteristic yellow spores that the plants produce in the horn-shaped sporophyte.
A sporophyte is the diploid multicellular stage in the life cycle of a moss which produces spores. They are commonly observed in this species. There is one sporophyte produced per perichaetium. [4] The seta, which is a stalk that supports capsule, is relatively short and is 25 mm in length. It is red-brown in colour and inserted laterally. [6]
There are three observed life history strategies for this genus: (1) heteromorphic diplohaplontic, the gametophyte (N) and sporophyte (2N) are both free-living and equally distinct bodies, however, the gametophyte (N) has a diminutive form and releases anisogamous (i.e., unequal in form and size) gametes to form the zygote (2N) which will later ...
Phaeoceros carolinianus is distinguished by its sporophyte, a horn-like structure that emerges vertically from the thallus. These horn-like structures reach 40–60 mm in height, with spores developing progressively from base to tip. Each sporophyte comprises a foot anchored in parent tissue and an elongated, spore-producing capsule.
They had essentially an isomorphic alternation of generations (meaning that the sporophytes and gametophytes were equally free living), which might suggest that both the gametophyte-dominant life style of bryophytes and the sporophyte-dominant life style of vascular plants evolved from this isomorphic condition. They were leafless and did not ...