In article <61h4rc$g5e at net.bio.net>, Brian Foley <btf at t10.lanl.gov> wrote:
> Bob Cooper wrote:
> >
> > Hi
> >
> > I had a student question about genes that code for tubulin and
> > flagellin. The flagella of prokaryotes and eukaryotes are analogous
> > structures. Prokaryotic flagella are composed of flagellin subunits
> > while the microtubules that make up the eukaryotic flagellum
> > (undulopodium) are composed of tubulin. Does anybody know if the genes
> > that code for these protein subunits (i.e., flagellin and tubulin) are
> > at all homologous?
> >
> > Bob Cooper
> > rac7 at erols.co>> First of all, the word "homologous" is supposed to mean
> "derived from a common ancestor". And this is usually a yes or
> no answer. There are not supposed to be differeing levels of
> "homology". However, people mis-use these terms in place of
> "similar" and and "similarity" so much, that I suppose we need
> to give up on the orignal definition.
>
Brian,
Here I go being orthodox again, but I have to disagree. I don't think we
should give up on the evolutionary definition of "homologous," just
because people misuse the word. There is a useful distinction between the
two, as you point out. I guess I will continue to try gently to correct
people (mainly molecular biologists) when they misuse the words homology
and homologous.
Jerry Learn
Research Associate
Health Sci. Ctr., Rm. K443-C |
Dept. of Microbiology | Learn at u.washington.edu
University of Washington | Phone: (206) 616-4286
Box 357740 | FAX: (206) 616-1575
Seattle, WA 98195-7740 USA |
