Fig6-E9.5-Tagln. [doi:10.1002/dvdy.10307] Copyright: This image is from Porter GA Jr; Makuck RF; Rivkees SA, " Intracellular calcium plays an essential role in cardiac development." Dev Dyn 2003 Jun;227(2):280-90. Reprinted with permission of Wiley-Liss Inc. [PMID:12761855] .