I'm trying to get a sense of the similarities between languages in syntax. How similar are Python, jQuery and C? I started programming in Actionscript 3 and then moved on to Javascript , then went on and learned Prototype, and then I started using jQuery and found that the syntax is very different. So is jQuery more like C and Python?
C is much different from the languages you've asked about.  Remember that C isn't an interpreted language and will not be treated as such in your code.  In short, you're up for a lot more material to learn --while dealing with C-- in terms of things like memory management and semantics than the other languages.
In regards to syntax: You'll find that if you're writing code in any language other than Lisp, brainfuck, or some other non-intuitive language (not claiming that C is, but in comparison, certainly), the syntax isn't too much of a variable. There are some differences, but nothing that should be considered too abstract. In C, you have to worry about things like pointers and whatnot which is a pain, but I think the difference is more-so about memory management than syntax.  You mostly have to worry about the differences in usages of semicolons and whatnot.
You'll find that Python is like writing English sentences, or at least writing pseudocode with constraints, which makes it significantly easier than C.  Additionally, I wouldn't consider jQuery a language on its own.  It's an extension of a language though, just as STL might be considered a particular type of extension to C++.
Good luck.
How similar are Python, jQuery, C syntax wise?