Subunit composition of Eukaryotic & Prokaryotic
subunits comprise one or two rRNA molecules, plus a
variable number of proteins.
Combinations of rRNAs and
typically have a smaller sedimentation rate (S) than their
component parts, due to condensation. In eukaryotes,
the complete 80S monosome
comprises a 40S Small Subunit
that includes the 18S rRNA,
and a 60S Large Subunit
that includes the 28S, 5.8S, and 5S rRNAs. Prokaryotic ribosomes
are somewhat smaller, but include analogous subunits.
Figure ©2012 TA Brown, Introduction
to Genetics (1st ed.); text ©2014 by
Steven M. Carr