Ecosystem Roles and Energy Transfer

The video tutorial covers the roles of producers, consumers, and decomposers in ecosystems, explaining energy transfer and transformation. It defines productivity terms and discusses autotrophs and heterotrophs. The tutorial explores ecosystem relationships like parasitism, mutualism, and herbivory, and examines closed systems. It highlights the essential role of decomposers and details energy fixation by autotrophs. The video concludes with a discussion on decomposers and nutrient cycling, ending with final questions and key concepts.

What is the primary role of autotrophs in an ecosystem?

• To produce secondary consumers

• To decompose organic matter

• To fix energy from the sun

• To consume other organisms

Which of the following best describes a secondary producer?

• An organism that produces its own food

• An organism that is a primary consumer

• An organism that decomposes organic matter

• An organism that feeds on primary producers

In a mutualistic relationship, both organisms:

• Are unaffected by each other

• Harm each other

• Benefit from each other

• Compete for resources

Why are consumers not absolutely essential in a closed ecosystem?

• They do not contribute to energy flow

• They are not involved in nutrient cycling

• Autotrophs can sustain themselves through photosynthesis

• They do not interact with decomposers

What is the main function of decomposers in an ecosystem?

• To consume autotrophs

• To break down dead organic matter

• To compete with primary producers

• To produce energy from sunlight

Which organism is considered a key decomposer in soil?

• Bracket fungus

• Cattle egret

• Cow

• Earthworm

According to the 10% rule, how much energy is typically transferred from primary to secondary consumers?

• 1%

• 10%

• 50%

• 100%

What is the significance of the 10% rule in energy transfer?

• It indicates the efficiency of energy transfer between trophic levels

• It explains why energy is lost during respiration

• It shows how energy is stored in autotrophs

• It describes the energy used by decomposers

How do earthworms contribute to soil health?

• By competing with other decomposers

• By producing nutrient-rich pellets

• By reducing soil aeration

• By consuming autotrophs

Which method can be used to estimate the gross primary productivity (GPP) of farmland?

• Measuring soil temperature

• Using oxygen and carbon dioxide sensors

• Counting the number of autotrophs

• Using light sensors