4.5 - Food Chains & Food Webs

• What is the main focus of today's video?

  Energy passing through an ecosystem
• What does a food chain illustrate?

  What gets eaten by what in an ecosystem
• How is a food chain different from a food web?

  A food chain shows one interaction chain
• What is the starting point of all food chains?

  A producer
• What type of organisms are producers?

  Photosynthetic organisms
• What does the term 'photosynthetic' mean?

  Organisms produce glucose using sunlight
• What is biomass?

  Biological molecules in a plant
• Who are the primary consumers in a food chain?

  Organisms that eat producers
• What is the role of secondary consumers?

  They feed on primary consumers
• What does the term 'tertiary' refer to in a food chain?

  The third level of consumers
• What happens to energy as it moves up the food chain?

  Most of it gets lost
• If there are 1,000 joules of energy in grass, how much energy is passed to the mice?

  About 100 joules
• How much energy might be passed on to the owl from the mice?

  About 20 joules
• What do the arrows in a food chain represent?

  The flow of energy up the chain
• How should the arrows in a food chain be drawn?

  To show energy flow direction
• What is the significance of energy loss in food chains?

  It affects ecosystem dynamics and stability
• What is the relationship between producers and consumers?

  Producers provide energy for consumers
• What are trophic levels in ecology?

  Levels of energy transfer in food chains
• Why is sunlight important in photosynthesis?

  It provides energy for glucose production
• How does energy transfer affect ecosystem dynamics?

  It influences population sizes and interactions