The
organisms in this phylum are among the most beauful in the microscopic world.
Unfortunantely people tend to overlook them because they comprise much of
what is commonly called "pond scum", itself a highly diverse andwonderful
biological community. These organisms are like plants in that they have
chloroplasts and cellulose cell walls. Unlike plants these organisms are
haploid and form strands of single cells.
The phylum gets its name because sexual reproduction involves a complete transfer of a haploid nucleus from one cell to another to form the zygote. Thus there are no sperm or eggs.
The picture to the left shows an unidentified filimentous member of this phylum. Clinging to the surface of the alga are numerous brownish yellow diatoms.
Many
of the members of this phylum have uniquely shaped chloroplasts. The image
to the left shows Spirogyra which gets its name from its huge spiral
shaped chloroplasts(arrows).