The simplest monosaccharides are _____________ and __________. Only _________ contains a ________ center.

Glyceraldehyde exists in two __________ forms.

A monosaccharide whose ______ ________ _________ center ( the ________ carbon) has the same configuration as the D-(+)-glyceraldehyde is designated as a __________. Vice versa for the L-(-)-glyceraldehyde.

The D and L nomenclature