The Molymod Biochemistry Student Set can be used to make quality, colour-coded 3D models, Designed to make most of the common structures necessary for the study of molecular biology. Atoms:. 12 x carbon (4 hole tetrahedral). 9 x carbon (3 hole, trigonal). 11 x oxygen (2 hole, angular). 2 x oxygen (1 hole). 3 x nitrogen (4 hole tetrahedral). 6 x nitrogen (3 hole trigonal). 2 x nitrogen (2 hole, angular). 1 x sulphur (2 hole, angular). 1 x phosphorus (4 hole, tetrahedral). 22 x hydrogen (1 hole). 3 x hydrogen (2 hole, angular). Bonds:. 40 medium grey.