The double helix can be reversibly melted Single stranded oog 1.3 o0 g Melting 1.1 temperature Double helical c1.0 60 70 80 220 300 Wavelength(nm) Temperature('C) Single-stranded DNA absorbs light The absorbance of a dna solution at more effectively than does double 260nm increased when the double helix helical DNA-----Hypochromism is melted into single strandsThe double helix can be reversibly melted Single –stranded DNA absorbs light more effectively than does double￾helical DNA-----Hypochromism. The absorbance of a DNA solution at 260nm increased when the double helix is melted into single strands