Gnetales

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Gnetales

an order of GYMNOSPERMS whose members have true vessels in the secondary wood and an absence of archegonia in the ovule. In these features they resemble ANGIOSPERMS.

Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

References in periodicals archive ?

Conifers can produce multiseriate rays if the rays contain resin canals, and Gnetales are all characterized by multiseriate rays.

Living Cells in Wood 3. Overview; Functional Anatomy of the Parenchyma Network

Pearson, Gnetales, Cambridge University Press, London, UK, 1929.

Preliminary Phytochemical Screening, Quantitative Analysis of Alkaloids, and Antioxidant Activity of Crude Plant Extracts from Ephedra intermedia Indigenous to Balochistan

Keywords: Chhidru Formation, Palynomorphs, Monocolpate, Sulcate, Gymnosperms, Peltasperms, Gnetales, Medullosales and Ephedralels.

LATE-PERMIAN MONOCOLPATE AND SULCATE POLLEN FROM CHHIDRU FORMATION, SALT RANGE, PAKISTAN

Xylem hydraulic and photosynthetic function of Gnetum (Gnetales) species from Papua New Guinea.

Aclimatacion de plantulas de Gnetum leyboldii Tul. (Gnetaceae) a los cambios de luz en un bosque lluvioso tropical

Phylogenetic relationships in Ephedra (Gnetales): evidence from nuclear and choloplast DNA sequence data.

Revision taxonomica y distribucion geografica de Ephedra (Ephedraceae) en Mexico

Several previously mentioned studies have used various gymnosperm groups (particularly the Gnetales) as outgroup.

The systematic position of the monocotyledons inferred from 26S RNA gene DNA sequences

Conifers and most members of the Gnetales (i.e., Ephedra and Welwitschia) express both prefertilization and postfertilization provisioning of embryo-nourishing tissues of the female gametophyte (Martens 1971; Singh 1978; Haig and Westoby 1989).

Heterochrony and developmental innovation: evolution of female gametophyte ontogeny in Gnetum, a highly apomorphic seed plant

Pollen chambers are known from the earliest fossils of Gnetales (Rothwell & Stockey, 2013).

Degradome and secretome of pollination drops of Ephedra

Structure and function of female and bisexual organ complexes in Gnetales. The International Journal of Plant Sciences 157: S113-S125.

A biophysical perspective on the pollination biology of Ephedra nevadensis and E. trifurca

Orbicules are omnipresent in Gnetales: Ephedra (El-Ghazaly & Rowley, 1997; Doores et al., 2007), Gnetum (Camiel, 1966), and Welwitschia (Zavada & Gabarayeva, 1991).

Orbicules in flowering plants: a phylogenetic perspective on their form and function

What Brown most importantly recognized, albeit in a somewhat circumlocutious way, was that in cycads, conifers and Gnetales, among extant seed plants, the ovules receive pollen directly, whereas in flowering plants the ovule, being enclosed within a carpel, cannot receive pollen, that being the function of the stigma.

Rescuing Robert Brown--the origins of angio-ovuly in seed cones of conifers

Rudall is doubtful that the monocot cambium is equivalent to secondary thickening meristematic activity in non-monocot angiosperms and Gnetales, and indeed, it is not.