Final answer:
Prion-based diseases such as Creutzfeldt-Jakob disease (CJD) are caused by the misfolding of a normal cellular protein called PrP. This misfolding leads to an exponential increase in the misfolded protein and the formation of brain lesions. Prions are transmissible and can cause fatal neurodegenerative diseases in humans and animals.
Step-by-step explanation:
The actual cause of prion-based diseases such as Creutzfeldt-Jakob disease (CJD) is the misfolding of a normal cellular protein called PrP (prion protein). PrP exists in two forms, PrPC (the normal form) and PrPSC (the infectious form). When PrPSC is introduced into the body, it converts PrPC into PrPSC, leading to an exponential increase in the misfolded protein that aggregates and forms lesions in the brain. Prions are transmissible and can cause fatal neurodegenerative diseases in humans and animals.