Macbook Pro Audio Input Not Working With Microphone

I am trying to connect microphone to my early 2011 17" MacBook Pro, but I cant get it working. MBP 17" has 2 audio jacks so I supposed the second one is for microphone but just doesnt work (Mac or Windows) and I gotta use USB audio card shipped with my headset.

Am I doing something wrong or the other jack is not supposed for audio input with classic 3.5mm microphone jack?

EDIT: I of course selected the Line-In device in preferences. The bar under device list wasn`t doing anything while I was talking, but when I was moving with the cable it blinked (I guess because I created some noise by moving the cable).

Actually, if you plug in an TRRS plug (the one with three rings on it) into the headphone jack, your Sound menu will switch from "internal mic" to "external mic" and you don't need a powered headset. So if you have a headset with two plugs, you'll need a combiner Y-adapter for that. They're about $4.

Edit: the TRRS plugs come on headsets like the iPhone headset as well. Those work fine.

Mac laptops have not supported a non-powered microphone input for years.
The input you see is a "line-in" input that requires more input signal level than a passive (non-powered) microphone can deliver.

You will need an additional pre-amp or active mic (a microphone with phantom power will suffice).

If you microphone has a physical mute switch, this can confound the Mac a bit. If you leave it muted, it seems either the port or the OS eventually decide there is no mic there and switch back to the internal/built-in mic.

When this happens, the only actions that work for me to get the mic recognized again are to: