I want to study for PhD in the US so I will have to take the GRE test. I'm a bit worried about getting bad results, especially in the general test, because I'm not a native English speaker. Will the institutions I apply to be able to tolerate a result that is a little lower than for US students? Surely, knowing words like "loquacious" (from the sample test) can't be the most important thing for a PhD in biology?

Where can one take the GRE test in order to do PhD in the US, do you know? Are there centers for that, how much does it cost and how to do to subscribe?

Take a look at www.gre.org

GRE is not essential.
Your acdemic background, recommendation letters and papers(SCI) are more important

So as long as I don't fail the test completely I should be ok then?