Will a MacBook Pro power on without memory card inside?

I bought a Macbook (2008)pro and there is no memory card, or charger. I got a charger and still waiting for the memory card from a seller I ordered it from.

In the meantime I plugged the charger and the charger light turned green, but when I pressed power button on macbook, it did not power on nor show any side lights at all.

So my question is, could it be because of the absence of Memory Card? Do Macbook powers on at all without memory? Btw, I charged the laptop for over 2hrs and it still won't power on.

Thanks in advance.