Energy Flow and Matter Cycling in Ecosystems

The video explores the cycling of matter and flow of energy in ecosystems. It begins with an introduction to how energy from the sun powers ecosystems and how matter cycles through them. The video explains the law of conservation of mass and how matter is recycled in ecosystems through processes like composting. It then discusses energy flow through trophic levels, highlighting the roles of primary producers, consumers, and decomposers. The complexity of food webs is explored, showing how they differ from simple food chains. Finally, the video covers energy transfer efficiency, introducing the 10% rule and explaining why energy is lost at each trophic level.

What is the main source of energy for most ecosystems?

• The wind

• The moon

• The sun

• The ocean

According to the law of conservation of mass, what happens to matter in an ecosystem?

• It is created and destroyed

• It is only created

• It is neither created nor destroyed

• It is only destroyed

What are primary producers in an ecosystem?

• Organisms that decompose dead matter

• Organisms that live in water

• Organisms that produce energy from the sun

• Organisms that consume other organisms

Which of the following is a primary consumer?

• Grasshopper

• Snake

• Alligator

• Owl

What is the difference between a food chain and a food web?

• A food chain includes all organisms in an ecosystem

• A food web is a linear sequence of organisms

• A food web consists of multiple interacting food chains

• A food chain is more complex than a food web

What factors can impact the size and scope of a food web in an ecosystem?

• Water, temperature, and sunlight

• Rock type, air pressure, and gravity

• Wind, soil type, and altitude

• Animal size, plant color, and humidity

What does the 10% rule in energy transfer state?

• 10% of energy is stored in the environment

• 10% of energy is created at each trophic level

• 10% of energy is transferred to the next trophic level

• 10% of energy is lost at each trophic level

Why is energy transfer in an ecosystem not completely efficient?

• Energy is stored in the soil

• Energy is lost as heat

• Energy is absorbed by the atmosphere

• Energy is converted into matter

What process do plants use to convert sunlight into chemical energy?

• Fermentation

• Decomposition

• Photosynthesis

• Cellular respiration

What happens to the energy stored in an organism when it dies?

• It is used by decomposers

• It is stored in rocks

• It is absorbed by the sun

• It disappears