What is it called when landforms are slowly worn down over time by outside forces?

Blood has traveled from the heart to the toes. which describes the next step of the circulation process?

Several bird species feed in a certain species of tree. each bird species feeds in a different part of the tree. which statement is true of these bird species? a. they have adapted to different niches due to competition b. they have a carnivorous relationship with the tree species. c. they have adapted to different niches due to predation d. they have a symbiotic relationship with the tree species.

In the respiration-photosynthesis cycle shown above, what are the products of cellular respiration that belong in box 2?