(A) Bending modulus difference between pure phospholipid membrane and protein-containing membrane. (B) The tension changes with relative area expansion without ATP (○) and with 1 mmol/L ATP (■). Reprinted with permission from Ref. [29]. Copyright©2005 American Physical Society. (C) Passive (red) and active (green) fluctuation spectrum of a single GUV containing BR. (D) Fit of active spectra by theory. Reprinted with permission from Ref. [115]. Copyright©2009 American Physical Society.