Ask A Scientist© Biology Archive

Question:  How are ribosomes constructed?
Garrett A Mayer

Answer:
They are made from large pieces of RNA (ribosomal) which are cut into smaller
pieces, joined with special binding proteins (about 50%) and assembled into
small and large subunits.  During the translation (protein synthesis) process
these small and large subunits bind onto mRNA and read and assemble the
amino acids coded by the base sequence on the RNA has special catalytic
properties necessary for this complex process.
 
Most antibiotics work by interfering with the normal function of ribosomes
found in prokaryotes (bacteria).  Bacteria die since they cannot make the
necessary proteins.  e.g. streptomycin and tetracycline.
 
Ribosomes are most likely assembled in the cytoplasm.  This is undoubtedly a very 
important organelle in terms of the evolution of life since all cells have
some form of ribosome.
louh