If you want be fastidious about apostrophes, then you have to use an actual apostrophe, not a “tick mark.”
Unbeknownst to many people, the “quotes” next to the enter key are way too easy to use. Likewise, it has become such a standard with the advent of desktop publishing, that actual typography has gone by the wayside.
If you want to insert a real apostrophe into HTML, then you must type the following combination: ’
right into your code or text. If you want to get sneaky and do it directly in an application, the hold down the ALT key and type 0146
then let up on the ALT key and your apostrophe will magically appear.
I even went so far as to write a web application
to parse out extended characters in a text string and convert it to propler HTML.
Oh, what dorks we are! :)