Some mitochondrial DNAs possess several D loops, reflecting the use of multiple origins. The same mechanism is employed in chloroplast DNA, where (in complex plants) there are two D loops.

TLS Online TPP Program

#Id: 8066

#Unit 13. Methods in Biology

Optically active chiral molecules will preferentially absorb one direction of the circularly polarized light. 

TLS Online TPP Program

#Id: 8067

#Unit 13. Methods in Biology

If an optically active molecule has a positive CD, then its enantiomer will have a negative CD of exactly the same magnitude.

TLS Online TPP Program

#Id: 8068

#Unit 13. Methods in Biology

TLS Online TPP Program

#Id: 8069

#Unit 13. Methods in Biology

A photoelastic modulator (PEM) is then used to convert the linearly polarized light into circularly polarized light.

TLS Online TPP Program

#Id: 8070

#Unit 13. Methods in Biology

An optically active chiral compound will absorb the two directions of circularly polarized light by different amounts

TLS Online TPP Program

#Id: 8073

#Unit 13. Methods in Biology

In a chiral medium the molar absorptivity of LCP and RCP light are different so they will be absorbed by the medium in different amounts.