Amino acid dating fossils
D) Early Earth’s atmosphere had significant quantities of ozone.3) What is true of the amino acids that might have been delivered to Earth within carbonaceous chondrites?A) They had the same proportion of L and D isomers as Earth does today. formation of DNA-based genetic systems A) I, II, III, IV B) I, III, II, IV C) II, III, I, IV D) II, III, IV, I5) Which of the following is a defining characteristic that all protobionts had in common?
A) B only B) C only C) D only D) B and C E) C and D The figure represents a cross section of the sea floor through a mid-ocean rift valley, with alternating patches of black and white indicating sea floor with reversed magnetic polarities.D) How could polymers involving lipids and/or proteins form membranes in aqueous environments?E) How can RNA molecules act as templates for the synthesis of complementary RNA molecules?C) The Cambrian explosion is evidence for the instantaneous creation of life on Earth. 42) Assuming that the rate of sea-floor spreading was constant during the 1-million-year period depicted above, Earth’s magnetic field has undergone reversal at an average rate of once every A) 10,000 years. Note: The horizontal arrows indicate the direction of sea-floor spreading, away from the rift valley.D) The Cambrian explosion marks the appearance of filter-feeding animals in the fossil record. 43) Which section of sea-floor crust should have the thickest layer of overlying sediment, assuming a continuous rate of sediment deposition?