How can you explain how genetic similarities are due to common ancestry? Where do we get our DNA from?

Actually our genetic code is unrepeatable, the union of the female x chromosomes of our mother and chromosomes and of our father, generate a diploid cell with a UNIQUE cellular genetic code.

What shows our descent from the same ancestor is mitochondrial DNA, this DNA is the same and is repeated throughout the human race.

Explanation:

Mitochondrial DNA is circular and is found in our organelle called mitochondria, responsible for cellular respiration and formation of the energy currency ATP-

yes you are doing it right great gob

explanation:

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.