Some geologists hypothesize that the mass extinction of dinosaurs was caused by a large meteorite impact. These geologists think the meteorite impact significantly changed Earth's climate. How could a meteorite impact do this?

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

When you run, you begin to breathe heavier and faster. your heart beats more quickly, bringing more oxygen to your cells. which organ systems are working together here?

Why do mountaineers become breathless as they reach high altitudes