What Determines the Shape of an Atom?

[hyurnat4]

This isn't exactly homework, but I'm still in high-school and I feel guilty posting in the big guys' forums.

I've recently learned about the shapes of spdf orbitals and the way they interact to form different bonds. This is completely different to the nice spherical atoms we were shown back in primary.

However, I recall seeing several photographs of atoms taken through a microscrope, and they were most definitely spherical. Can someone reconcile these conflicting ideas? What shape is an atom?

 

[Vorde]

It highly depends on how many electrons there are. Here is a picture of some various orbital shapes for one electron: http://chemwiki.ucdavis.edu/@api/deki/files/4826/=Single_electron_orbitals.jpg

Increasing the number of electrons and energy levels will only further complicate this.