With Alt+7 and Alt+9 you are simply inserting some "special" characters.
The paragraph isn't formatted as a real bullet list (a real bullet list indent the bullet character).
I think in google plus you can use any unicode character (e.g. some greek char: Σ, Ω, arrows: ⇨, ↻) but these are only characters and do not change the formatting of the characters (underline, color, size, etc...) or of the paragraph (bullets, numbered list, margin, alignment, etc...).
in windows, unicode characters can be inserted with some Alt codes (http://www.fileformat.info/tip/microsoft/enter_unicode.htm
), with the charmap (hit ⌘Win+R then type charmap then hit ⌅ Enter) or can be copied and pasted from any unicode table (http://www.babelstone.co.uk/Unicode/babelmap.html