What evidence BEST supports the presence of atmospheric oxygen 2.7 billion years ago? a. carbon 14 in plants
b. fossils found in stomatolites
c. layered iron rust in rocks

Choose a mutation from those in model 2 that would be neutral for a cell. explain your reasoning by relating the mutation to the cellular respiration process.

Radiometric dating is used to tell the absolute age of materials by studying the decay rate of radioactive isotopes. the decay rates of isotopes are constant and are expressed as .

Gram-negative bacteria have a cell wall that is! and does not accept the stain, making itappear