ABSTRACT
Marine algae vary in size from one-celled organisms a few millimeters in diameter to highly organized plants attaining a length of 30 meters. All algae capable of photosynthetic activity contain a pigment called chlorophyll, which is enclosed in cell inclusions called chloroplasts. The attachment and secretion phases of initial microbial fouling involve the proliferation, by both division and growth, of filamentous organisms. The resulting fibrous surface mats entrap particulate debris and are excellent new substrates for attachment of diatoms. Mucilaginous substances have long been implicated in the attachment of diatoms and microalgae. The secretion of exopolymers containing vesicles allows attachment of the diatom to surfaces and also facilitates movement of the frustule. Adhesion is strengthened by secretion of high molecular weight polymers, which are mainly polysaccharide in nature. The adhesive extracellular polysaccharide can be seen using the transmission electron microscope.
