Question

I can't remember how to tell if a molecule is hydrophobic orhydrophilic just by looking at it! Please someone help explain itto me (yes I feel stupid). It's been too long since chemistry &I am doing biochem.

I am looking at the molecules: glucose, tryptophan,testosterone, sodium dodecyl sulfate, and alsoguanine. Somebody please explain how to tell if each ofthese molecules are hydrophobic, or hydrophilic(polar)! As far as I can remember it has something to dowith charges...maybe...

Thanks!