The profusion of skin colors and physical characteristics of different humans is due to .

a. the development of pure races

b. the differences in climate and other living conditions humans encountered as they populated the globe

c. biology rather than evolution

d. the emergence of dominant groups in the last three centuries

Which best explains how a heat pump can heat a room? cold air from the house is moved through pipes, where it absorbs thermal energy. warm air from outside is pushed into the house to replace the cold air. combustion warms the air when chemical energy is transferred to thermal energy. fuel is used to move a piston, which pushes warm air into the house.

What organelle other than the nucleus houses dna in a eukaryotic cell?

The normal shape of an enzyme is as shown in structure a. if the enzyme’s shape changes to that shown in structure b, what are two consequences of this change?