<prompt> In response to changes in Ca2 concentration, which of the following Ca2 binding protein can modify the activity of many enzymes proteins?CalmodulinCollagenKinesinElastin  <response>: Calmodulin is a small 148 amino acids, 17 kDa ubiquitous protein in eukaryotes. It is considered as the primary intracellular calcium sensor, making it a key regulator of intracellular signal transduction. Ref: Harpers Biochemistry 26th Edition Page 463 ; E. coli Gene Expression Protocols By Peter E. Vaillancou, 2003, Page 69 