Biochemistry A small Ca+2 binding protein that modifies the activity of many enzymes and other proteins in response to changes of Ca+2 concentration is known as: A Cycline B Calmodulin C Collagen D Kinesin 💡 Explanation A small Ca+2 binding protein that modifies the activity of many enzymes and other proteins in response to changes of Ca+2 concentration is known as: ✓ Correct Answer: B. Calmodulin