Bill Nye: Rivers and Streams

Front

_______ flow together to form streams.

Back

Rills

Front

What causes the formation of waterfalls? Options: The erosion of soft rock, The erosion of very hard rock, The force of rills flowing downward, Chemicals in water due to industrial pollution.

Back

The erosion of soft rock

Front

Why are dams built?

Back

To provide flood control, harness hydroelectric power, and control the height of the river for safe navigation.

Front

Why do many fish lay their eggs in shallow pools of gravel?

Back

To prevent eggs from being washed downstream, to allow eggs to stick in the cracks of rocks, and to protect eggs from flowing into churning water.

Front

Where do many rivers in North America originate? Options: Death Valley, Rocky Mountains, Alaska

Back

Rocky Mountains

Front

The small streams where the river starts are called: Rills, Hills, Rivers

Back

Rills

Front

Water _______ the land it flows through.

Back

both of these are correct

Front

Water always flows ____ because every water molecule is pulled down by gravity.

Back

down

Front

Human cities & industries usually spring up around ____.

Back

rivers

Front

The more meanders in a river, the _____ it is.

Back

older