Biology 1002B Chapter Notes - Chapter Outcomes: Tetrachromacy, Dichromacy, Trichromacy
Document Summary
What accounts for the differences in absorption characteristics of the different rhodopsins. Changing the ways proteins folds changes the way retinal interacts with the protein. Then the way retinal binds is slightly different. Slight change in the way photons are absorbed. Major similarity and differences as revealed in protein alignment of sw, mw and lw opsins. Mw and lw are more similar to each other. Association between trichromacy, dichromacy, old world monkeys and new world monkeys. General distribution of dichromacy vs. trichromacy vs. tetrachromacy among vertebrates. Vertebrates have lost, and regained, cone pigments over time. Mechanisms to explain how and why, over evolutionary time, lineages may lose and regain opsin genes. Being able to disguise color isn"t useful if you don"t have enough light anyway. Their descendants also receive the same amount of opsins. Some may get their opsins back from a gene duplication event. If you"re finding food based on its shape than its color.