All of the above are correct.
Supragingival plaque is densely packed on the tooth surface about 0.5mm thick or more. Flagellated forms and spirochetes are observed apically and on the outer surface of the supragingival plaque.
Subgingival plaque has an outer and inner layer. The inner layer is tightly adherent but is thinner than and not as organized as supraginigal plaque. The outer layer adjacent to the soft tissue is loosely adherent layer. It is composed of the organisms in answer 5.
Formation of the dental pellicle is the initial stage of plaque formation. All surfaces of the oral cavity are covered with a glycoprotein. The mechanisms of pellicle formation are electrostatic, Van der Waals forces and hydrophobic forces. Within a few hours bacteria is found on the dental pellicle. The initial bacteria are gram-positive facultative bacteria such as Actinomyces viscosus and Streptococcus sanguis. The initial bacteria adhere to the pellicle by adhesions and fimbriae on the surface of the bacteria. As the plaque matures the bacteria become more gram-negative anaerobic organisms. Secondary colonization of bacteria that do not initially colonize clean tooth surfaces occurs. Coaggreagation is the term to describe different species of bacteria adhering to one another in mature plaque.
The Periodontic Syllabus, Third Edtion. Page 15
Clinical Periodontology, 8th Edition Page 86-88
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