Seeed Protoshield Kit for Arduino questions

Model STR104B2P Assembly instructions say not to solder ADC6 and ADC7 unless you are using a Seeeduino. What is the ADC6 and ADC7 that I'm not supposed to solder because I'm using Arduino Uno r3? I do not know what this refers to. Also, if anyone has any advice on using this Seeed Protoshield Kit, please let me know. I've ordered my Protoshield kit through Radio Shack, and it should be in tomorrow.
Ted, in Lake City, Michigan, USA

Uno uses DIP part, does not support ADC6 & 7. Those 2 are analog input only pins on SMD parts.