Need somecell-bio/biochem help about amino acids

**MR_T** · 09-14-2008, 07:24 PM

I know we have a few bio/chem people on here, hopefully somebody can help me out. I have an exam tomorrow, going over study guide questions and not sure about this one, my ochem is a little rusty

here is the question exactly as its written.

"Name the 3 major "R" groups of amino acids."

So if an amino acid has a generic structure of a central carbon with amino group, R group, and Hydrogen atom attached to it, Am I being asked what the most common(major) R groups are in the 20 common amino acids? or do the hydrogen, amino group and slide chain count as r groups since they are attached to a central carbon?

Also if the first guess was correct, what are the most common R groups in A.A's, Im studying the structures right now and I'm having a hard time finding a shared/common one

Thanks

**Phate** · 09-14-2008, 07:52 PM

There are basically three major classifications for amino acids (1) those with nonpolar R group, (2) those with uncharged polar R groups, and (3) those with charged polar R group.

**MR_T** · 09-14-2008, 08:20 PM

thanks bro, cant believe i didnt see that.. i was freaking naming each amino acids r group trying to find a pattern

**Phate** · 09-14-2008, 08:30 PM

it's cool bro, do you need to know which AAs are in each of the three categories as well?

**MR_T** · 09-15-2008, 01:45 AM

thanks bro I got it all down.. nothing like the cram right before the test, cant wait to kick some ass

**IronReload04** · 09-15-2008, 08:03 PM

havent had the biochem yet, but I willl

you gonna be able to get some sleep tonight bro?

what time is the test?

**MR_T** · 09-16-2008, 12:09 PM

test was at 10, stayed up till 3 studin, Test was way easier than i expected kind of wasted my time over details etc. and his questions were more conceptual... live and learn