Spider are apparently absent. In some species, the exocuticle of the legs and prosoma is modified by a tanning process, resulting in brown coloration. Bilins are found, for example, in "Micrommata virescens", resulting in its green color. Guanine is responsible for the white markings of the European garden spider "Araneus diadematus". It is in many species accumulated in specialized cells called guanocytes. In genera such as "Tetragnatha", "Leucauge", "Argyrodes" or "Theridiosoma", guanine creates their silvery appearance. While guanine is originally an end-product of protein metabolism, its excretion can be blocked in spiders, leading to an increase in its storage. Structural colors
Botanical Garden of Tver State University Garden identified the following sectors: The following departments: The Division is divided into sub-sections: Small-leaved mixed forest, broadleaf forests, oak, the site of the South European deciduous forests Placed on the territory of some 350 species. The most widely represented the family Araceae (about 50 species), Orchidaceae (about 20 species), Polypodiaceae (about 30 species), Arecaceae (15 species), Bromeliaceae (10 species), Agavaceae (10 species), Gesneriaceae (10 species), Liliaceae (10 species). At the station placed 135 species. Most of the species collected in the collection of natural habitats. Represented by steppe species, for which the Tver region is the northern boundary of