They form under a pressure and heat that doesn't destroy the fossils. Igneous and metamorphic rock form from molten rocks thus reaching a temp that destroys the fossils within.
What would happen if M RNA were radio actively labeled instead of polypeptides is that instead of one seeing the DNA passing through all the molecular factories you will instead see just messenger RNA taking code and delivering it to Ribosome. This is mainly found in cytoplasm and Endoplasmic recticulums.
They're the only vein that carries oygenated blood
Copper deficiency is a rare disease that leads to hematological disorders. It is an essential trace element. It is an essential part of some enzymes (c0-factor) that plays role in cellular respiration. Copper is also an anti-oxidant that scavenges free radicals. In case of cellular respiration copper is responsible for electron transfer of oxygen.
C seeds because plants grow from seeds