Word geekery, aka word of the day

adrenergic
definition 1, given in the chapter on drugs: mimicking the action of the sympathetic nervous system; sympathomimetic
definition 2, given in the chapter on the nervous system: describes activity involving epinephrine

Things you need to know to understand this:
1. epinephrine = adrenaline
2. The sympathetic nervous system controls the "fight or flight" reaction - i.e., things involving adrenaline.
3. Epinephrine, like acetylcholine and dopamine and... (I think there's a couple more, but you probably don't need to know that part!), is a neurotransmitter, meaning a chemical that the nervous system uses to send out instructions.


columbina  and I were discussing this word a while back; it was initially used as a general term for drugs like Sudafed. Neither one of us had ever heard it before. So when it came up again in this chapter, with a completely different definition, I was interested. The thing that gave me a sudden "aha" moment was that there was a parallel adjective for acetylcholine: cholinergic. One word-part that I tend to miss over and over is "erg," as in ergo, work. (I think I tend to read it as part of the "like or pertaining to" ending of adjectives, like "-ic.") But if nervous system activity involving epinephrine is adrenergic and activity involving acetylcholine is cholinergic - even I didn't manage to miss that one. (Also bear in mind that the trade name Sudafed is basically short for pseudo-epinephrine - in other words, it's a stimulant. I am not clear on why that should help to clear up your nose, though. Anybody?) So really the difference beween the two definitions is that they're talking about adrenergic drugs vs. the chemicals that your body manufactures on its own.

I finished going through this chapter; now I have to review the two chapters (the endocrine system and the nervous system); then there's just one more chapter, which is just called The Senses. One chapter and three tests, including the final. Yuck. Sometimes I think I'm never going to finish this.