Small Things Considered

Talmudic Question #98

What do you think is the single best criterion for telling an endosymbiont of a eukaryotic cell from an organelle?

Post Script

I must come clean and confess that I formulated this question after having read a most stimulating review by John McCutcheon and Nancy Moran that touches on this subject. Some of the responses you provided are related to considerations in this article. Read and enjoy!

-Elio

Talmudic Question #97

by Welkin Johnson

What is the minimum set of adaptations that HIV would have to acquire in order to become a successful airborne pathogen like influenza?

Talmudic Question #96

Bacterial cells are smaller than eukaryotic cells, with some exception. Viruses are smaller than bacteria, with some exception. These are just two examples of why definitions in Biology, unlike in Physics and Chemistry, most often need to be qualified. What does this tell us about Biology?

Talmudic Question #95

by Barry Goldman

Almost all multicellular critters known (animals, plants, fungi, algae) go through a microbial stage in their life cycle - gamete or spore. Can you think of a multicellular species or higher taxon that has NEVER been caught going through the microbial stage?

Talmudic Question #94

by Mark Martin

Bacterial bioluminescence is ubiquitous in marine environments, both among free living and mutualistic microbes. Why is this phenotype comparatively rare in terrestrial and freshwater environments (the fascinating Photorhabdus being a notable exception)?

Talmudic Question #93

by Paul Evans

Which  bacteria besides the rhizobia undergo terminal (irreversible) differentiation?  (no fair saying 'spores')

Talmudic Question #92

Does DNA do anything other than serve as a repository for genetic information?

Talmudic Question #91

Why don't eukaryotes (with few exceptions) have operons in their genomes?

Talmudic Question #90

by Welkin Johnson

Is it conceivable that, in evolution, a virus could switch from one genome type and replication style to another?

Talmudic Question #89

Of the ~10³⁰ prokaryotic cells on Earth, what proportion would you guess are viable (using your favorite criterion for viability)?