what are characteristics of Gnetophyta?
Gnetophyta is consider as a linkage between gymnosperms and angiosperms based on a few characteristics found in gnetophyta.
inflorescence best answer:
Answer by Peter S
Vegetative Characteristics: Plants are trees, shrubs, lianes, or stumpy turnip-like. Leaves are simple, opposite or whorled, strap-like in Welwitschiaceae, angiosperm-like in Gnetaceae, or scale-like in Ephedraceae. Secondary xylem contains vessels, as in angiosperms, although the homology of the vessels in the two phylum is in question.
Reproductive Characteristics: Plants are usually dioecious with "flowers" unisexual in compound strobili or "inflorescences". Female flowers have one (rarely paired), erect ovule, a nucellus of two or three coats, and micropyle projecting as a long tube. The female gametophyte often lacks organized archegonia. Male cone mostly compound, and associated with bracts. Fertilization occurs through pollen-tubes with two male nuclei. Double fertilization is recorded for some members of the phylum as in angiosperms, although the two are not exactly homologous. Insect pollination is likely due to cone exudations .
inflorescence
Chorizanthe brevicornu
The inflorescence bracts are paired, a diagnostic trait of Chorizanthe. The tubular structures are involucres, which enclose typically two flowers. The involucres have about 6 recurved (uncinate) teeth around the distal end (rim of the opening), which is distinctive to a subset of species of Chorizanthe. This species is noted for its erect to ascending growth habit and stems that disarticulate at the nodes by late summer and fall.
Orignal From: what are characteristics of Gnetophyta? and Chorizanthe brevicornu
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