Energy Flow and Ecosystem Productivity

Mr. Andersen explains energy flow in ecosystems, focusing on the role of producers, photosynthesis, and chemosynthesis. He discusses productivity, energy measurement, and the efficiency of energy transfer through trophic levels. The video compares productivity across biomes and highlights the importance of ecological pyramids in understanding energy distribution. Key concepts include gross and net primary productivity, the role of decomposers, and the impact of seasons on productivity.

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

• The Moon

• Volcanoes

• Wind

• The Sun

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

• Chemosynthesis

• Respiration

• Fermentation

• Photosynthesis

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

• Gross is only for aquatic plants, net is for terrestrial

• Gross is the total energy converted, net is after respiration

• Gross is the energy lost as heat, net is the energy stored

• Gross is the energy after respiration, net is before

In an ecological pyramid, what percentage of energy typically transfers from one trophic level to the next?

• 100%

• 1%

• 50%

• 10%

Which biome is known for having high productivity?

• Savanna

• Tropical Rainforest

• Desert

• Tundra

What is the main reason for seasonal changes in net primary productivity?

• Soil composition

• Water availability

• Changes in sunlight

• Animal migration

In the Silver Springs energy pyramid, what is the approximate ecological efficiency from primary to secondary consumers?

• 20%

• 5%

• 16%

• 10%

What role do decomposers play in an energy pyramid?

• They consume primary consumers

• They produce energy

• They recycle nutrients

• They store energy

How is biomass different from productivity in ecological studies?

• Biomass is measured over time, productivity is at one point

• Biomass is the total mass, productivity is the rate of energy conversion

• Biomass is the energy stored, productivity is the energy used

• Biomass is only for plants, productivity is for all organisms

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

• Standing crop

• Gross primary productivity

• Net primary productivity

• Ecological efficiency