scalariform


Also found in: Dictionary, Encyclopedia.

scalariform

(skə-lăr′ə-fôrm′)
adj. Biology
Resembling the rungs of a ladder; ladderlike. Used of certain tissues and cells.

scalariform

ladder-like.
Mentioned in ?
References in periodicals archive ?
The list of similarities between the two genera includes: vessels solitary or in small groups; helical sculpture on walls of vessels; vessel to vessel pitting alternate; vessel to axial parenchyma and vessel to ray pitting scalariform to transitional; pits non-vestured; scalariform perforation plates or modifications of them scarce, but present throughout the secondary xylem; imperforate tracheary elements are septate fibers with simple or vestigially bordered pits; axial parenchyma scanty vasicentric and terminal; bordered pits present on cross-walls of the strands of axial parenchyma; multiseriate rays wide, with tip and sheath cells upright but ray cells otherwise procumbent; uniseriate rays composed of upright cells.
Perforation plates mostly simple, but occasionally scalariform or scalarifonn-like, both in wide and narrow vessels (Fig.
Each cell has eight to 10 layers of scalariform thickenings, this character gives the seed a deep honeycomb appearance.
The combination of the size and shape of cells that make up the testa, the ornamentation of the radial walls of those cells, and the number of scalariform thickenings in the testa allow for precise identification at the species level.
Unfortunately, a table of Baas & Wheeler (1996) combines both the pit evolution and evolution of simple perforation plates from scalariform perforation plates, so we cannot separate their reversion estimates for these two characters.
41 times as wide as long, with scalariform , strongly shouldered whorls.
What is the syndrome of features associated with the scalariform pitting pattern of tracheary elements?
Sieve plates are scalariform, showing radial and tangetial distribution in sieve elements and a high staining reaction for cellulose and hemicellulose.
1930): "In view of the proof offered that the transition from the protoxylem to the secondary xylem represents a primitive to specialized sequence which is palingenetic, and the accurate portrayal this sequence gives the change from scalariform to porous perforations, there is little reason to doubt that the detailed transitions here illustrated give a connected picture of the evolution of the scalarifiorm vessel segment from the scalariform tracheid" (1930, pp.
4 mm wide, 1090 mm long wide, 2249 mm long Endwalls nearly vertical, Endwalls nearly vertical, exclusively scalariform exclusively scalariform Perforation plates average 37 bars Perforation plates average 27 bars per plate per plate Intervascular pits opposite Intervascular pits opposite Parenchyma diffuse, scanty Parenchyma diffuse, apotracheal and paratracheal scanty paratrachial Rays heterogeneous, 1-3 cells wide Rays heterogeneous, 1-3 cells wide Crystals absent Crystals absent
The secondary xylem has scalariform or pitted (biseriate-triseriate) tracheids.
Families in which both scalariform and simple perforation plates have been documented in the same species, among different species, or both, are listed in Table I.