A tree's roots grow into narrow cracks in a boulder. Over many years the cracks widen and pieces of rock break off. Which interaction does this describe?

A river slowly carves a deep valley through solid rock over thousands of years. In this example, which sphere is changing which?

A wildfire burns through a dry forest and sends thick smoke and gases high above the treetops. Which interaction does this show?

Earthworms and beetles tunnel through a garden, dragging dead leaves down with them. What effect do these living things have on the soil?

A tree pulls water up from the soil through its roots, and water vapor leaves its leaves into the air. Which interaction is this?

Rain soaks into the ground and collects in spaces between rocks. Later, deep roots pull that underground water up to a tree's leaves. Which spheres does this connect?

During one heavy rainstorm, a grassy hillside keeps almost all of its soil while the bare hillside beside it loses a great deal. What does this show about plants?

Beavers cut down small trees and build a dam across a stream. The water backs up and turns a meadow into a wide pond. Which interaction does this show?

Mosses and lichens spread across a bare boulder. After many years the rock surface crumbles and a thin layer of soil sits on top. What is happening?

A student claims that living things change the air around them. Which observation best supports that claim?

Steady ocean wind blows across a coastal hillside. The trees there grow short and lean away from the sea, while trees in a sheltered valley grow tall. Which interaction is this?

Grasses and shrubs grow thickly on one sand dune. A nearby dune has no plants at all. On a windy day, which dune keeps most of its sand in place, and why?

Fungi and worms break down the fallen leaves covering a forest floor. What happens to the nutrients from those leaves?

Wind lifts dry soil from a bare field, carries it for miles, and drops it onto the surface of a lake. Which spheres interact in this event?

A student's model of how living things and rock affect each other has arrows only from the geosphere to the biosphere. What is the main problem with this model?

Coral reefs are built by living animals, and their hard remains add rock-like material to the ocean floor.

A town plants rows of leafy trees beside a dusty road. Dust from the air collects on the leaves instead of blowing into homes. What does this show?

Which observation best supports the claim that the atmosphere affects the biosphere?

A young tree's roots grow under a sidewalk and lift the concrete until it cracks. Which event works in the same way?

Two equal soil plots got the same amount of water. It soaked into the plot full of earthworm tunnels in 1 minute. It took 6 minutes to soak into the plot with no worms. What do these measurements show?