Ecosystem Dynamics and Energy Flow

What does the Law of Conservation of Mass tell us about matter?

• Matter can be created but not destroyed.

• Matter can be destroyed but not created.

• Matter can be created and destroyed.

• Matter cannot be created or destroyed.

What do plants take in from the air and soil to grow?

• Carbon dioxide, water, and nitrogen

• Oxygen, sugar, and light

• Sunlight, heat, and wind

• Biomass, decomposers, and energy

What is the job of decomposers like worms and bacteria in an ecosystem?

• To make their own food using sunlight.

• To eat other animals for energy.

• To break down dead matter and return it to the environment.

• To produce oxygen for other living things.

What are plants called because they can make their own food using sunlight?

• Heterotrophs

• Primary consumers

• Autotrophs

• Decomposers

Why are food webs a better way to show how energy moves in an ecosystem than food chains?

• Food webs only show plants.

• Food webs are simpler and easier to understand.

• Food webs show how many different food chains are connected.

• Food webs only show animals that eat other animals.

What things can change the size and type of a food web in an ecosystem?

• The color of the sky and the number of clouds.

• The amount of water, temperature, and sunlight.

• How many animals are sleeping and how many are awake.

• The type of soil and the height of the trees.

What happens to most of the energy as it moves through a food chain?

• It stays the same in every animal.

• It is created by the animals.

• It is lost as heat.

• It turns into water.

What do plants take in to make their own food during photosynthesis?

• Sugar, oxygen, and heat.

• Water, carbon dioxide, and sunlight.

• Animals, soil, and air.

• Other plants and rocks.

Why do animals like caterpillars do cellular respiration?

• To make more plants.

• To get energy from food.

• To turn into butterflies.

• To make water and carbon dioxide for plants.

What is the "10% rule" in a food chain?

• Only 10% of animals can eat plants.

• Only 10% of the energy from one level is passed to the next level.

• Animals only eat 10% of their body weight.

• Plants only use 10% of the sunlight they get.