Friday, May 09, 2008

You too can understand science talk ...

... by grasping the meaning of the prefixes and suffixes commonly used by individuals in science.

I have used and explained several of them recently in this blog, but we'll go over them again, as well as a few others.

Yesterday I spoke about the Acidobacteria. Sometimes just looking at the word can reveal a clue as to the physical capabilities of the organism in question. As indicated, Acidobacteria fare extremely well in acidic conditions (pH's under 7.0). They are what is known as acidophilic.

Acido/philic (adjective)
Acido- = acid
-philic = loving

Acidophilic = Acid loving (i.e., they prefer to grow in acidic conditions).

So, acidophilic is an adjective. The noun would be acidophile.

Alkalo/philic (adjective)
Alkalo- = alkaline (basic solution, pH above 7.0)
-philic = loving

Alkalophilic = Alkaline loving (i.e., they prefer to grow in alkaline conditions). The noun is alkalophile.

What are some other words:
aero- = involving air (e.g., aerobic)
an- = without (if we couple an- with aero- we get anaerobic which means lacking air)
anti- = against
bi- = two (e.g., biphasic means two phases)
di- = two
-phobic = fearing (e.g., acidophobic means fear of acid)
pseudo- = false (e.g., pseudogene)
psychro- = cold (e.g., psychrophilic means cold loving)
-phore = carry (see next)
sidero- = iron (e.g., siderophore means an iron carrying molecule)
therm- = heat (e.g., thermophilic means heat loving)

So, that's a few examples, and how some of them work together to give us common terms used in microbiology. A lot of these prefixes and suffixes have Greek and Latin roots. A book I first used, at least a decade ago, was compiled by Gylys and Wedding entitled Medical Terminology: A systems approach. You can find early editions of this text at places like Abe Books for cheap (by cheap I mean $1).


kldickson said...

Is there some sort of finer distinction between 'psychro-' and 'cryo-' in bacteriology? I have not heard, ever, 'psychro-' being used in other biomedical fields (although this is from my limited perspective as a student in only one of those fields), and the OED definition of 'psychro-' seems identical to 'cryo-'.

Tom said...

Good question. Psychropiles are microbial organisms which generally thrive in temperatures between 0 and 15 degrees C. I've always seen the prefix cryo- used in conjunction with below freezing temperatures. So I would assume while the words are somewhat interchangeable, it's the difference between saying "It's chilly (psychro) and It's freezing (cryo) outside". They both indicate cold, but their ranges are different.