Final answer:
The cellular form of the prion is found in vertebrates. Prions are misfolded proteins that can cause diseases like transmissible spongiform encephalopathies (TSE).
Step-by-step explanation:
The cellular form of the prion, known as PrPC, is found in vertebrates. Prions are misfolded proteins that can cause diseases like transmissible spongiform encephalopathies (TSE). PrPSC, the infectious form of the protein, binds to PrPC and converts it to PrPSC, leading to the aggregation of abnormal proteins and brain damage.