Hi Maytha, The most basic way to select parts of an atomic model within a map is to ctrl-click with the left mouse button on an atom or ribbon residue. Then the up-arrow key on the keyboard will expand the selection to the containing helix or strand, and pressed again to the whole chain. Maybe you don't have an atomic model -- hard to tell from your question. Tom

On Sep 24, 2023, at 1:05 PM, MAYTHA ALSHAMMARI <malsh009@odu.edu> wrote:

Dear Goddard,

I hope you're well. I have a quick query about selecting parts of a structure within a boxed map in Chimera. Can you provide some guidance or instructions on how to do this effectively? Your help is much appreciated.

Best regards, Maytha