No you cannot. You are not seeing any wireless card at all. What you have is a virtual internet adapter which is made to communicate with your host's working interface, be that ethernet or wifi, or3G, or whatever. But from within the VM you cannot control the wifi card any more than you can control the ethernet card.
Yet there is a way around that: if you have a USB wifi adapter, you may get control of that. And if you do, it will look like a true,physical wifi card, which you can use any way you like it, for instance you can put it in monitor mode.
But, I repeat, only with an external wifi card. For use with backtrack (then, why backtrck? why do you not move up to kali linux?) it is expedient to use a high gain wifi USB antenna. Any online store is replete with models satisfying this description; but do make sure, before buying one, that it works with Kali by reading the forum, here.