Distinction between function types

Hi I'm am currently working on a question on Big O notation and to work out $O(n^k)$ of $f(n)$ you first need to know what type of function $f(n)$ is, polynomial, exponential, logarithmic. My question is does the degree of a function determine what type of function it is?

For example is:

$67n^3 − 40n^2 + 6n + 3 \log_2 n − 33$ a polynomial function

$3 \log_2 n − 33$ a logarithmic function

$2^n + 40n^2 + 6n + 3 \log_2 n$ an exponential function

My specialty is more programming so this isn't too obvious to me :(

Any help would be much appreciated!

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What is degree of a function for you in this context? –  Hagen von Eitzen May 10 '13 at 13:59
high sorry , it's the maximum term in the function as n increases to infinity –  Neo May 10 '13 at 14:31