Botanique

In this chapter, you will become familiar with brown algae.

This includes:

• Phaeophyceae sensu stricto (true brown algae)

• Diatoms (unicellular algae that are part of plankton)

Both groups are now classified within the kingdom Chromista, a diverse group of eukaryotic organisms.

Other members of the Chromista kingdom include:

• Oomycetes (water molds, some of which are plant pathogens, e.g., Phytophthora)

• Chrysophytes (golden algae)

• Xanthophytes (yellow-green algae)

• Cryptophytes (unicellular flagellates found in marine and freshwater environments)

• Haptophytes (e.g., Emiliania huxleyi, important in marine ecosystems)

These organisms are mostly photosynthetic or heterotrophic and are often aquatic, playing essential roles in ecosystems as primary producers, decomposers, or pathogens.