Google Chrome - hidden and invisible extensions by default

Chrome does hide some internal extensions , you can see them right here: chrome://system/ Could Google use them for tracking? How to delete them? ------- List of extensions i see: gfdkimpbcpahaombhbimeihdjnejgicl : Feedback : version 1_0 kmendfapggjehodndflmmgagdbamhnfd : CryptoTokenExtension : version 0_9_73 mfehgcgbbipciphmccgaenjidiccnmng : Cloud Print : version 0_1 mhjfbmdgcfjbbpaeojofohoefgiehjai : Chrome PDF Viewer : version 1 neajdppkdcdipfabeoofebfddakdcjhd : Google Network Speech : version 1_0 nkeimhogjdpnpccoofpliimaahmaaome : Google Hangouts : version 1_3_10 nmmhkkegccagdldgiimedpiccmgmieda : Chrome Web Store-Zahlungen : version 1_0_0_4 pkedcjkdefgpdelpbcmbmeomcjbeemfm : Chrome Media Router : version 7118_1015_0_0