Panel 1: L-(-) Glyceraldehyde

Panel 2: D-(+) Glyceraldehyde

Glyceraldehyde is an aldotriose (three carbon sugar with an aldehyde functional group) with one chiral carbon (yellow halo). Having one chiral carbon, glyceraldehyde has two stereoisomers which are enantiomers. The enantiomeric pair is shown above as rotatable structures (rotation of the structure in Panel 2 rotates the structure in Panel 1) The structures are positioned so that the most oxidized group (aldehyde) is at the top of the structure, the vertical bonds of the chiral carbon are projecting into the plane of the screen and the horizontal bonds are projecting out of the plane of the screen toward you. Rotate the structures as needed to confirm that the bonds are projecting as described. When these structures, being in the position described, are projected on to a 2D surface, the 2D Fischer projections are formed. When in the Fischer projection, the hydroxyl group on the chiral carbon of D-glyceraldehyde is on the right side of the molecule, and it is on the left with L-glyceraldehyde. The orientations of the atoms or groups on the non-chiral atoms are not specified.