Titlebook: Sieve Elements; Comparative Structur H.-D. Behnke,R. D. Sjolund Book 1990 Springer-Verlag Berlin Heidelberg 1990 Assimilat.algae.antibody.b

lethal

Cycads and Gnetophytes,main expansion in Jurassic and Cretaceous times. Consequently, their extant species (some 100 in the cycads and about 70 in the gnetophytes) are regarded as the specialized remnant of a once very successful line which in the Devonian has the same origin as the Coniferophytina, i. e., in the so-calle

ULCER

Dicotyledons,est attention in the literature on phloem. By definition, the sieve elements of dicotyledons are sieve-tube members; that is, sieve elements in which some of the sieve areas are more highly specialized (having larger pores) than others and are localized on the walls to form sieve plates (Esau 1969).

小歌剧

Monocotyledons,sis being placed on the main conducting unit, the sieve element. One of the most controversial issues of phloem investigation has been the nature of the mature sieve-plate pores: open or occluded? A clear understanding of sieve-element structure at successive stages of development is thus of fundame

新义

Sieve Elements in Internodal and Nodal Anastomoses of the Monocotyledon Liana ,,e elements throughout the entire plant body. The requirement for this integrity is nowhere better documented than in the formation of wound (repair) phloem (see Chaps. 10 and 11), but even the undamaged plant ensures that there are channels for a deviation of solutes in the case of an injury or if a

BAN

慢跑

dilute

祝贺

Sieve Elements in Haustoria of Parasitic Angiosperms, assimilatory organs. Water as well as organic substances must be taken up, therefore, by specialized haustoria (Kuijt 1969; Kollmann and Dörr 1987). The faster the parasite grows, the more efficient must be the cells developed specifically for nutrient transport.

俗艳

–LOUS