Suppose you are a cell??

[Robert A. Bloodgood]

When asked which cellular organelle I would give up, I think the clear answer
is the mitochondrion.  It is possible to do so in yeast.  During evolution,
there are good examples of cells that gave up mitochondria, when evolving in
a low oxygen environment...a good example is the wealth of flagellated
protozoa (such as Trichonympha, Barbulanympha, Pyrsonympha) that live in the
hindgut of lower termites and the wood-feeding roach, Cryptocercus.  These
organisms are highly motile, anaerobic and have no mitochondria.  I believe
that Pelomyxa is a free-living amoeba that also lacks mitochondria.
                                Regards,  Bob Bloodgood