Your biceps might not be the true definer of your strength, but what guy who puts a ton of work in the gym like the results of big biceps, especially for the ladies. So even though the bicep is generally a stabilizer muscle, don't forget about sculpting them properly when in the gym.
When doing your bicep curls, try one of the many techniques that keep your back from helping you lift, and isolate your biceps. One variation of sitting bicep curls is playing your elbow in your inner thigh, and curling from just above the floor to slightly above perpendicular to your leg.
Another techinique is placing an adjustable bench at a fairly steep incline, and while seated on the bench, curl dumbbells again from slightly above the floor (relaxed position) to the full curl motion. This takes your back completely out of the equation isolating the biceps getting the best results for the muscles.