Energy Flow in Ecosystems

The video tutorial explains energy pyramids and food webs, focusing on how energy flows through a food chain and is represented in an energy pyramid. It covers the 10% rule of energy transfer, where only 10% of energy is passed to the next trophic level, while the rest is used or lost as heat. The tutorial also differentiates between food chains and food webs, highlighting the complexity of energy flow in ecosystems. Practice questions are provided to reinforce understanding.

What do the arrows in a food chain represent?

• The lifespan of organisms

• The growth rate of organisms

• The flow of energy between organisms

• The direction of food consumption

How much energy does a grasshopper use for its daily activities?

• 90%

• 100%

• 50%

• 10%

What is the primary purpose of an energy pyramid?

• To illustrate the flow of water in an ecosystem

• To measure the speed of energy transfer

• To display the available energy at each trophic level

• To show the number of organisms at each level

If a grass has 10,000 kilocalories, how much energy does the grasshopper receive?

• 1,000 kilocalories

• 10,000 kilocalories

• 10 kilocalories

• 100 kilocalories

What percentage of energy is typically passed on to the next trophic level?

• 5%

• 50%

• 10%

• 20%

How much energy does the hawk receive if the snake has 10 kilocalories?

• 100 kilocalories

• 0.1 kilocalories

• 1 kilocalorie

• 10 kilocalories

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

• A food web is linear, while a food chain is complex

• A food chain includes all organisms in an ecosystem, while a food web does not

• A food web shows multiple energy paths, while a food chain shows a single path

• A food chain shows multiple energy paths, while a food web shows a single path

In a food web, what does the variety of arrows indicate?

• The multiple directions of energy flow

• The speed of energy transfer

• The size of the ecosystem

• The diversity of organisms

If the prawn has 9,250 kilocalories, how much energy does the algae have?

• 925 kilocalories

• 9,250,000 kilocalories

• 9,250 kilocalories

• 92,500 kilocalories

What role does a producer play in an energy pyramid?

• It is at the bottom and has the most energy

• It is at the top of the pyramid

• It has the least energy

• It is in the middle of the pyramid