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In mosses, the peristome is a specialized structure in the sporangium that allows for gradual spore discharge, instead of releasing them all at once. Most mosses produce a capsule with a lid (the operculum ) which falls off when the spores inside are mature and thus ready to be dispersed.
Sori may be covered by a structure called an indusium. Some ferns have their sporangia scattered along reduced leaf segments or along (or just in from) the margin of the leaf. Lycophytes, in contrast, bear their sporangia on the adaxial surface (the upper side) of leaves or laterally on stems. Leaves that bear sporangia are called sporophylls ...
In botany, a sporophyll is a leaf that bears sporangia. Both microphylls and megaphylls can be sporophylls. In heterosporous plants, sporophylls (whether they are microphylls or megaphylls) bear either megasporangia and thus are called megasporophylls, or microsporangia and are called microsporophylls. The overlap of the prefixes and roots ...
A strobilus (pl.: strobili) is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem.Strobili are often called cones, but some botanists restrict the use of the term cone to the woody seed strobili of conifers.
Eusporangiate ferns are vascular spore plants, whose sporangia arise from several epidermal cells and not from a single cell as in leptosporangiate ferns.Typically these ferns have reduced root systems and sporangia that produce large amounts of spores (up to 7000 spores per sporangium in Christensenia).
The spores are dispersed through a catapult-like system, flinging the spores out briefly at up to 10m/s. This is caused by the gradual build up of a high negative pressure (200-300 atmospheres) within annulus cells from water loss. [1] As these cells lose water, they shrink, and are designed to inwardly bend on the outer face of the annulus.
Distinct from a synctium, a multinucleate structure resulting from fusion of protoplasts. [69] colony A massed group of hyphae and spores of a single species, especially if all are grown from a single spore (e.g. in a lab). [70] columella. pl. columellae. A sterile central axis within a fruiting body (sporocarp) or sporangium. [71] complicate
For Banks, rhyniophytes comprised simple leafless plants with terminal sporangia (e.g., Cooksonia, Rhynia) with centrarch xylem; zosterophylls comprised plants with lateral sporangia that split distally (away from their attachment) to release their spores, and had exarch strands of xylem (e.g., Gosslingia).