Final answer:
The pseudomembrane formed by Corynebacterium diphtheriae in diphtheria patients is composed of fibrin, dead tissue, and bacterial cells.
Step-by-step explanation:
The pseudomembrane formed by Corynebacterium diphtheriae, which is the causative agent of diphtheria, is composed of fibrin, dead tissue, and bacterial cells. This membranous layer can cover mucous membranes of the nasal cavity, tonsils, pharynx, and larynx, and it's a result of the diphtheria toxin produced by the bacterium after colonization of the throat. This toxin interferes with host-cell protein synthesis, causing cell death and an inflammatory response that leads to the formation of the pseudomembrane.