Energy Transfer and Ecosystem Productivity

Mr. Andersen explains energy flow in ecosystems, focusing on the role of producers and consumers. The sun is the primary energy source, with energy transferred through photosynthesis and chemosynthesis. Productivity is measured as gross or net primary productivity, with energy efficiency assessed using ecological pyramids. A case study of Silver Springs, Florida, illustrates energy transfer and ecological efficiency. The video concludes with a review of key concepts, emphasizing the importance of understanding energy flow and biomass in ecosystems.

What is the primary source of energy for ecosystems on Earth?

• The Ocean

• Volcanoes

• The Moon

• The Sun

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

• Respiration

• Photosynthesis

• Fermentation

• Digestion

Which of the following is a chemical used in chemosynthesis?

• Carbon dioxide

• Hydrogen sulfide

• Nitrogen

• Oxygen

What is the main difference between gross primary productivity and net primary productivity?

• Gross includes respiration, net does not

• Net includes respiration, gross does not

• Gross is measured in water, net in air

• Net is always higher than gross

Which biome is known for having the highest productivity?

• Desert

• Tundra

• Tropical Rainforest

• Savanna

What percentage of energy typically transfers from one trophic level to the next?

• 50%

• 90%

• 1%

• 10%

In an ecological pyramid, which level contains the most energy?

• Secondary consumers

• Tertiary consumers

• Producers

• Primary consumers

What role do decomposers play in an ecosystem?

• They produce energy

• They consume producers

• They increase energy efficiency

• They recycle nutrients

How does the energy efficiency of an ecosystem typically range?

• 1% to 5%

• 20% to 50%

• 5% to 20%

• 50% to 100%

What is the term for the amount of biomass present at a given time?

• Trophic level

• Standing crop

• Gross primary productivity

• Net primary productivity