Becker's World of the Cell 9th Edition by Lewis Kleinsmith, Jeff Hardin, Gregory Paul Bertoni

Exercise 4

Calcium Chelators and Ionophores. In addition to calcium ionophores, another tool that has aided studies of the role of Ca 2+ in triggering different cellular events is calcium chelators. Chelators are compounds such as EGTA and EDTA that bind very tightly to calcium ions, thereby reducing nearly to zero the free (or available)Ca 2+ concentration outside of the cell. Using these tools, describe how you could demonstrate that a hormone exerts its effect by (1)causing Ca 2+ to enter the cell through channels or (2)releasing Ca 2+ from intracellular stores such as the ER.