the Cage of a green plant. Plazmodesmy

you are: the Cage of a green plant

Above we noticed that plazmalemma reliably separates a protolayer from a cellular wall surrounding it. It is impossible to consider, however, that the protolayer is completely delimited by this membrane from all other protolayers in a fabric. Protolayers of the next cages are undoubtedly informed with each other quickly and effectively because growth represents vysokointegrirovannyj process. this fast message is facilitated thanks to numerous plazmodesmam - cytoplasmatic tjazham, penetrating plazmalemmu, and also a cellular wall and connecting cytoplasm of the given cage with cytoplasm of all next cages (fig. 2.33). Plazmodesmy on the structure remind narrow tubules in diameter from 20 to 100 nanometers. As structures in the size less than 500 nanometers do not give in to the permission in a light microscope, to learn something about a structure plazmodesm it was possible only rather recently, with the advent of corresponding methods of electronic microscopy. In everyone plazmodesme, apparently, there is a channel - it names desmotrubochkoj, - on which various substances can pass from one cage in another. According to some biologists, desmotrubochki represent one of updatings endoplazmaticheskogo retikuluma as they form a single whole with endoplazmaticheskim retikulumom in those cages which they among themselves connect. Other researchers believe, however, that desmotrubochki the structures named microtubules which we will describe more low more remind.

Plazmodesmy connect among themselves the most part of cages of the higher plant. Their frequency even for different walls of the same cage strongly varies: from 100 000 to 50 million on 1 мм2 a cellular surface. it is no wonder that larger and more numerous plazmodesmy meet in those cages which exchange among themselves significant amounts metabolitov. In sites where it is concentrated especially much plazmodesm, the cellular wall is often very thin; such sites are called as steam fields.