Must for guys i rly need on ! its a biology question and i cant answer it for the life of me, so :

explain the purpose of a molecular clock and the properties that a section of protein must have to be used in this way.

be sure to answer this question in paragraph form using complete sentences.

levels of molecular variation could be used in principle to estimate divergence times, serving as evolutionary 'clocks' that 'tick'at different rates.

properities: the molecular clock hypothesis posits that the rates of molecular evolution, as reflected in the changes in DNA or protein sequences through time, are constant among lineages. so if you dont use it properly you could be in the completely different lineage

b. lithosphere, asthenosphere, mesosphere   is the answer most likely