Uma célula somática, que tem quatro cromossomos, ao se dividir, apresenta na metáfase:
a) quatro cromossomos distintos, cada um com duas cromátides.
b) quatro cromossomos distintos, cada um com uma cromátide.
c) quatro cromossomos, pareados dois a dois, cada um com duas cromátides.
d) quatro cromossomos, pareados dois a dois, cada um com uma cromátide.

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.

answer; polycythemia is the correct answer;