Ecosystem Dynamics and Energy Flow

Paul Andersen explains Life Science Core Idea 2B, focusing on matter and energy transfer in ecosystems. The video covers basic concepts for elementary students, such as the difference between organisms and the environment, and progresses to middle school topics like energy flow and food webs. For high school students, it discusses ecological pyramids and energy transfer, emphasizing the conservation of matter and the ten percent rule in energy transfer.

What is the primary distinction between organisms and their environment?

• Organisms and the environment are both non-living.

• Organisms and the environment are both living.

• Organisms are living, while the environment is non-living.

• Organisms are non-living, while the environment is living.

Which process is highlighted as a way to recycle matter in ecosystems?

• Photosynthesis

• Composting

• Respiration

• Evaporation

What role do decomposers play in the ecosystem?

• They store energy for future use.

• They consume producers directly.

• They break down dead material and return matter to the environment.

• They produce energy from sunlight.

In a food web, what do the arrows represent?

• The movement of energy and matter.

• The flow of water.

• The direction of sunlight.

• The growth of plants.

What is the main purpose of photosynthesis in plants?

• To produce oxygen for animals.

• To convert sunlight into usable energy.

• To decompose organic matter.

• To release energy from food.

How does cellular respiration benefit animals?

• It stores energy for later use.

• It helps them absorb sunlight.

• It allows them to produce their own food.

• It breaks down sugars to release energy.

What is an ecological pyramid?

• A structure showing the flow of water in an ecosystem.

• A diagram illustrating the distribution of matter, energy, and organisms across different levels.

• A chart showing the growth rate of plants.

• A map of animal migration patterns.

Why are there generally more producers than consumers in an ecosystem?

• Consumers reproduce more slowly.

• Producers are more diverse.

• Energy is lost at each trophic level, requiring more producers to support consumers.

• Producers are larger in size.

What is the 'ten percent rule' in ecological pyramids?

• Only ten percent of organisms survive each year.

• Ten percent of energy is transferred to the next trophic level.

• Ten percent of water is retained in the ecosystem.

• Ten percent of sunlight is absorbed by plants.

In a coral reef ecosystem, which level has the highest biomass?

• Top predators

• Primary consumers

• Producers

• Decomposers