Use the term "event" for your "section". An event is a single note or control operation (like a MIDI message) and all the things that affect it in one channel at the same time.
You can delete an event in one shot, but that's the extent of whole-event modifications while the cursor is in one field.
I think a "Select Event" would be helpful, in case you want to move, copy, or paste it. It would select the event that the cursor was in no matter what field it occupied.