How many swallows for a shot?

I don’t know if I am the only one, but 50ml seems like a lot to swallow at once. What I don’t mean is the drinking itself – as in, obviously you don’t sip a shot, but shoot it in your mouth, then swallow. What I mean is, is the shot of vodka then supposed to be swallowed in a single swallow? Or is it broken down into two? I have never done it in a single swallow, it seems as though I would choke, it’s way too much at once.