what are the characteristics of Gnetophyta?
inflorescence best answer:
Answer by Formerly 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
Artemisia frigida
The inflorescence bracts are dissected in a similar manner to the stem leaves. All flowers can produce a viable fruit and the receptacle is hairy, feature that related prairie sagewort to absinthium and alpine sagebrush.
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