Oedogonium

Oedogonium is occurring in freshwater green algae from the genus - group of the Chlorophyceae. It contains around 450 species.

Features

The representatives form unbranched filaments of a cell number. The threads have a diameter of 3 to 60 microns. The nucleus is located in the cell center, the chloroplasts are parietal, reticulate and possess pyrenoids. The formation of cap cells makes the genre unique: in the vegetative cell division within the thread does not make one daughter cell, an annular cap, the second. This repeats with each cell division, so that cap cells can carry many terminal caps.

Asexual reproduction takes place by large stephanokonte zoospores. This escape separately from normal thread cells. Sexual reproduction takes place by oogamy: individual cells form a bulbous oogonium. In special short cell ( antheridium ) one or two male sperm are formed. After fertilization creates a Dauerzygote. Many species have dwarf males as an intermediate stage: the laid-off from the short cell flagellated cell does not meet with the egg, but settles near the oogonium and here forms a small, wenigzelligen thread, the so-called dwarf males. This makes one or two antheridia, from each of which escapes a spermatozoid.

Occurrence

The members of the genus mostly live snugly in standing or flowing, predominantly nutrient-poor waters. More rarely, they occur freely floating. They occur mainly in the spring.

Documents

• K.-H. Linne von Berg, K. Hoef -Emden, B. Marin, M. Melkonian: The Cosmos algae leader. The main freshwater algae under the microscope. Kosmos, Stuttgart 2004, pp. 260, ISBN 3-440-09719-6