I have been often asked what the differences are between the various subdisciplines of the biomedical (or “life”) sciences.
That’s a tough question – but I’ll give it a try …
Basically biochemists play with proteins. Usually this involves fancy machines that cost a ton of money. Proteins are subjected to centrifugation, electrophoresis, fast protein liquid chromatography …. Incidentally these techniques are just sophisticated ways of pushing and shoving proteins around. If enough proteins clump together, biochemists get excited and call the clump a complex. If the complex is really big, the biochemist will call it the somethingosome. If you ask a biochemist to show you pretty data, he/she’ll show you his/her bands. Biochemists kill cells for their precious bodily fluids.
Cell biologists are the psychiatrists of the cellular world. They observe cell “behavior” through a microscope. They give cells drugs. They probe cells with microinjector needles. They shine big lasers … well it’s not always clear what they do with their lasers. A cell biologist asks big cellular questions like “How do cells crawl?” and “What is the meaning of dynamic instability?”. At the end of the day, just before heading to the bar, cell biologists fix their subjects in either formaldehyde or a nice tall cool glass of methanol. These cells are then subjected to immunofluorescence and produce the dreaded colocalization death-trap-data … beware if anyone gives you this type of data. When a cell biologist isn’t killing cells, he/she is in a dark bar (cell biologists hate sunlight), getting wasted.
Geneticists make mutants – that’s it. You might think that this sounds boring, but you have to see it from their perspective. They’re like the druids, or the freemasons … in others words some club. Well really 3 or 4 clubs: fly geneticists, worm geneticists, yeast geneticists, and others. Incidentally this last group is the weirdest – they chant incantations such as “the awesome power of yeast genetics”. And that’s not to say that the others aren’t weird. For example, fly geneticists torture the rest of the biological establishment by giving crazy names to their mutant flies (for example Sunday driver – whose neurons have aberrant vesicular traffic). The key to being a successful geneticist is to set up a good “genetic screen“. If you ever meet geneticists, ask them about their screen; it’ll make them happy. Using their powers, geneticists have probably had the most insightful discoveries of all the disciplines described here. Geneticists kill whole organisms, not only to find out what gene they’ve “knocked-out”, but to see how their poor mutant creations look. Scary.
These guys are strange hybrids of android-robots and neurotic psychopaths. Well actually, when they’re not injecting themselves with caffeine (necessary to pipette one microliter aliquots a million times over), structural biologists are pretty nice guys. The key to structural biology is pick out a “hot” protein (or ribonucleic acid) and purify it. What is a hot protein? You know something to do with some disease, RNAi or anything that sounds hard to deal with (such as membrane proteins). Some structural biologists throw their protein sample in a big magnet; others spend three years in a vain attempt to crystallize it. After they figure out how to make crystals, the structural biologists fly over to the synchrotron in Chicago, blast their crystal with a monster X-ray beam and then race each other on tricycles. Structural biologists kill small furry animals, but only in their spare time.
Molecular biologists study things that end in NA. No, this is not an abbreviation for Not Applicable, but for Nucleic Acid, THE POLYMERS OF LIFE …. eh hem … In a strange paradox, some molecular biologists perform biochemistry. And just like a biochemist, molecular biologists love bands. When they’re not playing hookie with the cell biologists at the local pub, molecular biologists kill anything that have NAs in them, so beware.
Well actually this is a description of an electrophysiologist (but the the rest of us call them physiologists). When you think of physiologists (or “molecular physiologists”) think of one word … electrodes. They stick electrodes everywhere, stimulating and measuring electric potentials as if tomorrow were the end of the world. If they are feeling good about themselves, physiologists will use the smallest darn instrument used on biological samples — the PATCH CLAMP. This measures the current coming out of a single ion pore. Cell biologists with their puny microinjectors are jealous of physiologists’ patch clamps. Physiologists don’t just kill animals, but will rip the beating heart out of their poor victims. Keep them away from your pets.
Developmental biologist are like geneticists, but even more specialized. If geneticists were the card carrying free masons, developmental biologists are their recluse hermit cousins. Each developmental biologist specializes in some arcane feature (for example the pancreas) and know every minutiae of their obsession. This leads them deeper into the darkest part of the forest. Eventually this trail leads to transcription factors and signaling pathways. Once they come back to civilization and discuss their findings, all the other biologists flee from their histological slides. Some of the scariest things you’ll hear from a developmental biologist is the words “promoter bashing” (it’s some satanic procedure that they picked up from the molecular biologists). Again instead of killing organisms like geneticists do, developmental biologists go one step further and kill fetuses.
System biologists are the newest branch on the life-sciences tree. No one is sure who, or what they are, only that some of them are ex-string physicists, others are bioinformatics guys, and the rest are biologists who have spent too much time playing Simcity or Civilization. Systems biologists collect data from all the other disciplines and then build their own fancy computer generated models. When they’re done they head over to the pub and show off their fancy flow diagrams to the other biologists. Those systems guys try hard to impress the others, using words like “in silico”, but no one pays any attention. If they’re really desperate, systems guys will start using words ending with ‘omics. Since systems biologists would love to kill, but not sure how to do it, they are mostly harmless.
This is really a modifier, like “smelly”. In a strange paradox, microbiologists use one of the approaches described above (such as biochemistry, genetics or molecular biology) but have their own society and meetings (I guess they want to feel good about themselves). Microbiologists kill bacteria OR yeast (for historic reasons only) … however, many “yeast people” now deny that they had anything to do with microbiology. Thus microbiologists now are mostly prokaryote researchers. With all the funding to bioterrorism, some microbiologists are actually quite happy these days.
I could describe virologists, neurobiologists, immunologists, plant biologists and other disciplines, but they would sound something like the description for microbiologists, but with obvious modifications.
As for the wider branches of the life science tree (ecology, evolution …) well they’re all at the main campus, so you’ll have to ask someone who works there.