If there is no family history of a particular disease but a child has the disease as well as the responsible genetic mutation in every cell, then it may have arisen due to a(n) mutation early during development.

layer 3 is younger than layer 6.

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.

answer( increase) their individual contractile activity;