Step wedge : printed series of density increases, in regular steps from transparent to opaque. Its a method of making exposure tests when enlarging.
Deoxyribonucleic Acid [DNA]
Deoxyribonucleic acid is a molecule that encodes the genetic instructions used in the development and functioning of all known living organisms and many viruses. DNA and RNA are nucleic acids; alongside proteins, they compose the three major macromolecules essential for all known forms of life.
