Earth’s Life-Support System
Living & Nonliving Parts
Energy in Ecosystems
Nature’s Cycles
People & the Environment
100

The thin layer of air around Earth.

What is the atmosphere?

100

The living parts of an ecosystem are called this.

What are biotic factors?

100

A simple line showing “who eats who.”

What is a food chain?

100

The cycle that moves water through clouds, rain, rivers, and oceans.

What is the water cycle?

100

The top layer of soil that plants need to grow.

What is topsoil?

200

The three things that keep life going on Earth: energy from the sun, cycling of nutrients, and ______.  

What is gravity?

200

Plants and algae that make their own food.

What are producers?

200

A bigger map of many food chains combined.

What is a food web?

200

The cycle that moves carbon through the air, plants, animals, and back.

The cycle that moves organic compounds through the air, plants, animals, and back.

200

When soil gets washed or blown away.

What is erosion?

300

This “blanket” of gases traps heat and keeps Earth warm.

What is the greenhouse effect?

300

Animals that eat other organisms for food.

What are consumers?

300

About how much energy passes from one level to the next (like from plants to herbivores)?

What is 10%?

300

The nutrient that helps plants grow but can pollute water if there’s too much.

What is phosphorus (or nitrogen)?

300

Using too much fertilizer can cause this problem in lakes.

What is algae overgrowth (algal bloom)?

400

The four “spheres” of Earth (air, water, land, life).

What are atmosphere, hydrosphere, geosphere, and biosphere?

400

Mushrooms and bacteria that break down dead stuff.

What are decomposers?

400

The process plants use to turn sunlight into food.

What is photosynthesis?

400

When plants release water vapor from their leaves.

What is transpiration?

400

The term for Earth’s “goods and services” like soil, water, and clean air.

What is natural capital?

500

Energy comes in, gets used, and then leaves Earth as this.

What is heat?  

500

A group of the same kind of organism living together.

What is a population?

500

The main reason food chains don’t go on forever.

What is not enough energy at the top?

500

A way humans change the carbon cycle (name one).

What is burning fossil fuels / cutting down trees?

500

What would happen if decomposers disappeared?

What is waste would pile up and nutrients wouldn’t recycle?