Selections created in Channels Panel disappear.

I have been watching tutorials on using Channels to adjust HSB, but I am missing something and I am looking for suggestions. This is what I'm doing:

• Copy original
• Select copy
• Go to Channels Panel
• Select Green layer
• Ctrl-click Green icon - Selection loads
• Click RGB
• Return to Layers Panel - the copy of original is selected & showing selection
• Create Adjustment Layer - Hue/Saturation - Selection disappears and H/S sliders affect the whole image, instead of Selection