Subject: How do I find what is in a spreadsheet

I see a spreadsheet (which I inherited from some one). Spreadsheet has radio buttons, pop-up list, charts. When you select a radio button, certain charts show up …
However when I go to Visual Basic Editor, I do not see any form. I only see under excel objects, sheet name. I wonder where exactly logic for selecting a radio button or pop-up list is written when VB editor does not show anything other than sheet name.

Thanks.
Prem