do_shortcode() in twentyeleven theme

Question

I observed a difference between twentyten and twentyeleven themes. Let me explain with an example: example.com/category/health-beauty/ finds one post containing just a shortcode.

If I use twentyten, nothing is displayed but in twentyeleven the shortcode is expanded. Actually this is what I want twentyten to do as well but the problem is I cannot find any do_shortcode call in twentyeleven code. There has to be one. Right?