ABSTRACT
In Chapter 1.2, it was noted that algae differed in their nutrition from the bacteria, fungi and protozoans in indoor environments. Algae are autotrophic; they obtain the carbon that is required for the biosynthesis of the organic molecules that make up their structure solely from carbon dioxide. This they are able to do because they are photosynthetic, utilizing light energy for the reduction and incorporation of the carbon dioxide. Although most of the algae in indoor air are of outdoor origin, they are able to grow indoors on perpetually damp surfaces exposed to light, e.g. on wet window reveals or on the soil of potted plants.
