hard parts are most likely to be preserved
Answer: Paleozoic
Explanation:
Not as many rocks existed from the precambrian era
Arteries are blood carrying vessels which have thick, elastic, muscular walls, have no valves and in which blood flows under high pressure. The make up of arteries is unique to their function of transporting blood under high pressure.
All arteries carry oxygenated blood from the heart to all other parts of the body, with the exception of the pulmonary artery which carries de-oxygenated blood from the heart to the lungs. It is the only artery that transports blood which has not been oxygenated.
Mutations. Definition. A Mutationoccurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene. A Mutagen is an agent of substance that can bring about a permanent alteration to the physical composition of a DNA gene such that the genetic message is changed