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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 ...
The Lycopodiopsida are distinguished from other vascular plants by the possession of microphylls and by their sporangia, which are lateral as opposed to terminal and which open (dehisce) transversely rather than longitudinally. In some groups, the sporangia are borne on sporophylls that are clustered into strobili.
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.
Reconstruction of Aglaophyton, illustrating bifurcating axes with terminal sporangia, and rhizoids. Modern polysporangiophyte, monarch fern is a vascular plant. Scientific classification; Kingdom: Plantae: Clade: Embryophytes: Clade: Polysporangiophytes Kenrick & Crane (1997) Subgroups non-vascular fossil Polysporangiophytes †Horneophytopsida ...
The leaves contain a single, unbranched vascular strand, and are microphylls by definition. [6] They are usually arranged in spirals. [ 7 ] The kidney-shaped (reniform) spore -cases ( sporangia ) contain spores of one kind only, ( isosporous, homosporous ), and are borne on the upper surface of the leaf blade of specialized leaves (sporophylls ...
In extinct groups, further protection was afforded to the spores by the presence of whorls of bracts - big pointed microphylls protruding from the cone. The extant horsetails are homosporous, but extinct heterosporous species such as Calamostachys casheana appear in the fossil record. [6] The sporangia open by lateral dehiscence to
Fern spores are borne in sporangia which are usually clustered to form sori. The sporangia may be covered with a protective coating called an indusium. The arrangement of the sporangia is important in classification. [6] In monomorphic ferns, the fertile and sterile leaves look morphologically the same, and both are able to photosynthesize.
The leaves are microphylls, each containing only a single vein and measuring less than 1 cm (0.4 inches) long. Two types of microphylls are formed, green trophophylls that cover most of the aerial shoots, and yellow to tan sporophylls that form the strobili, and contain the sporangia.