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Chloragogen cells, also called y cells, are star-shaped cells in annelids involved with excretory functions and intermediary metabolism. These cells function similar to the liver found in vertebrates. Chloragogen tissue is most extensively studied in earthworms. [1]
A cuticle (/ ˈ k juː t ɪ k əl /), or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non- homologous , differing in their origin, structure, function, and chemical composition.
English: The fine scale structure of a leaf featuring the major tissues; the upper and lower epithelia (and associated cuticles), the palisade and spongy mesophyll and the guard cells of the stoma. Vascular tissue (veins) is not shown. Key plant cell organelles (the cell wall, nucleus, chloroplasts, vacuole and cytoplasm) are also shown.
A plant cuticle is a protecting film covering the outermost skin layer of leaves, young shoots and other aerial plant organs (aerial here meaning all plant parts not embedded in soil or other substrate) that have no periderm. The film consists of lipid and hydrocarbon polymers infused with wax, and is synthesized exclusively by the epidermal cells.
Oligochaetes are well-segmented worms and most have a spacious body cavity (coelom) used as a hydroskeleton.They range in length from less than 0.5 mm (0.02 in) up to 2 to 3 metres (6.6 to 9.8 ft) in the 'giant' species such as the giant Gippsland earthworm (Megascolides australis) and the Mekong worm (Amynthas mekongianus).
In response to ecosystem disturbances, some sites have utilized earthworms to prepare soil for the return of native flora. Research from the Station d'écologie Tropicale de Lamto asserts that the earthworms positively influence the rate of macroaggregate formation, an important feature for soil structure. [ 67 ]
In earthworms, the clitellum can only be seen when the worm is sexually mature. It may be white, orange-red or reddish-brown in colour. Earthworms are ready to mate when their clitellum is orange. [2] In leeches, the clitellum appears during mating season, where it is used for both sexual reproduction and the secretion of a cocoon for the eggs. [4]
The structure and physiology of the calciferous glands of earthworms are described. Many hypotheses had been advanced for their function; Darwin believed them to be primarily for excretion and secondarily a digestion aid. Thin leaves are seized with the mouth, while thick ones are dragged by creating a vacuum.