Viruses are infectious agents that are not classified as living organisms.

State two life processes that viruses cannot carry out independently (when outside a host cell).

Name one disease in humans that is caused by a protoctist pathogen.

Prions are infectious pathogens composed entirely of protein material folded into an abnormal, disease-causing shape. Prions do not contain any nucleic acids.

Suggest two structural or functional differences between prions and typical viruses.