TABLE I.

DISCRIMINATIVE CHARACTERS OF VIRUSES AND PROTISTS OR BACTERIA

	Virions	Protists
Nucleic acid	DNA or RNA	DNA and RNA
Reproduction from the sole genetic material	+	0
Growth	0	+
Division	0	+
Information for the synthesis of enzymes of the energetic metabolism	0	+
Presence of the enzymes	0	+
Information for the synthesis of transfer RNA	0	+
Information for the synthesis of ribosomal RNA	0	+
Presence of ribosomes	0	+