Association for Biology Laboratory Education

Why Should I Wear Sunscreen? Ultraviolet Radiation, DNA, And Mutations
 

Sheila Kratzer and Charlene M. Waggoner

Tested Studies in Laboratory Teaching, 1997, Volume 18

Abstract

Ultraviolet radiation is part of the electromagnetic spectrum that comes to the earth from the sun. DNA absorbs ultraviolet radiation and forms thymine-thymine dimers. If these errors are not repaired, the DNA is altered and no longer codes for the original message. In humans, this damage can result in uncontrolled growth or skin cancer. In bacterial cells, which reproduce asexually, these mutations are passed onto the daughter cells. If the amount of radiation is sufficient, the cells will not reproduce. This can be observed in the laboratory by exposing plated cultures of Serratia marcescens (available from American Type Culture Collection) to a source of ultraviolet radiation.

Keywords:  mutation, Serratia marcescens, cancer, ultraviolet

Boston University (1996)