Remarkable Plants: The Oedogoniales (Green Algae) (DVD)
University level; General Interest
30 minutes, Produced in Australia (2004)
The Oedogoniales are a remarkable group of filamentous green algae. Their method of cell elongation after mitosis is unique, seen nowhere else in the plant kingdom; it utilizes a donut-shaped ring of soft wall material which is stretched by turgor pressure into the shape of the new daughter cell. Oedogonium is a simple filament. The related Bulbochaete and Oedocladium are quite different: both are branched and the former differentiates numerous long hair cells. The zoospore is a large, multiflagellated cell with an extraordinarily complex flagellar apparatus. Sexual reproduction is oogamous and of two patterns, macrandrous and nannandrous, the latter relying extensively on hormonal interactions to synchronize sexual maturation. Differentiation of oogonia and antheridia is initiated by highly asymmetric cell divisions and fertilization is rapid and efficient.
All these aspects of their biology are vividly illustrated in color by time lapse video microscopy. These are further supported by Teacher’s Notes downloadable from this web site, containing background information and references. This video is an essential aid for those who teach phycology and will fascinate anyone who is interested in the way ‘simple’ cells live and evolve.