1. What important gas do we take in when we breathe?

In the family tree below, people with the recessive trait of attached earlobes are shaded gray.

How does a gymnosperm prevent itself from pollinating the same tree

During the winter, this species of fox has white fur, but in the summer, it has brown fur. what environmental change may have lead to this fox's fur color? snow cover increase in sun's brightness volcanic eruption global warming