Unit 4: Biological Productivity

Front

What are Diatoms?

Back

Diatoms are a type of microalgae found in oceans, waterways, and soils, characterized by their unique silica cell walls. They are key primary producers in aquatic ecosystems.

Front

What is the average energy transfer from primary producers to second-order consumers?

Back

On average, only about 10% of energy is transferred from one trophic level to the next, so if primary producers contain 10,000 kcal, second-order consumers would receive about 1,000 kcal.

Front

Describe the energy flow in an ecosystem.

Back

Energy flow in an ecosystem is unidirectional, meaning it moves in one direction from producers to consumers and eventually to decomposers.

Front

What percentage of biomass is decomposed in the euphotic zone?

Back

Approximately 90% of biomass is regularly decomposed within the euphotic zone, which is the upper layer of water where sunlight penetrates.

Front

What happens when catches exceed the maximum sustainable yield?

Back

Catches above the maximum sustainable yield result in overfishing, which can deplete fish populations and disrupt the ecosystem.

Front

Define primary productivity.

Back

Primary productivity is the rate at which energy is converted by photosynthetic and chemosynthetic autotrophs to organic substances.

Front

What is the role of primary producers in an ecosystem?

Back

Primary producers, such as plants and phytoplankton, convert solar energy into chemical energy through photosynthesis, forming the base of the food web.

Front

Explain the concept of trophic levels.

Back

Trophic levels represent the hierarchical levels in an ecosystem, where each level consists of organisms that share the same function in the food chain.

Front

What is the significance of the euphotic zone?

Back

The euphotic zone is significant because it is the upper layer of water where sunlight allows photosynthesis to occur, supporting aquatic life.

Front

What are secondary consumers?

Back

Secondary consumers are organisms that eat primary consumers; they are typically carnivores or omnivores in the food chain.