In article <534sbq$gg9 at epervier.CC.UMontreal.CA>,
meilleus at MAGELLAN.UMontreal.CA (Meilleur Sebastien) writes:
>Black Orb (blackorb at aol.com) wrote:
>: Could someone help me out with this question??
>:>: - Why do ribosomes appear to be the first membrane bound organelle
that
>: developed in procaryotic cells??
>:
>Let me take a guess. I'd say because ribosomes are essentials to the
>synthesis of other proteins? Maybe since they are an important part of
the
>traduction of mRNA in proteins they had to be first. As I said this is
>only a guess without any deep research.
>>Anyone else has anything on this?
>Yes, I think I have another part of the answer.
Protein synthesis is not the only function of the ribosomes. Their
location in the cell give an hint about what they do.
In the case of procaryotic cells, free ribosomes assume protein synthesis
and Membrane Bound Ribosomes participate in the plasmic membrane
invagination process : they degrade essential food to provide the cell
with basic elements.
Although important, these MBR are not always first created, it depends on
the metabolism, cell type, and the medium in which the cell lives.
These ribosomes also exist in Eucaryotic cells.
These two cases are not the only functions of ribosomes.
PS : please excuse my english.
Isabelle, Pharmacology student.