c4.2

These flashcards cover key concepts related to ecosystems, energy flow, and the carbon cycle.

What are ecosystems characterized as?

Open systems where both energy and matter can enter and exit.

In an ecosystem, what is matter primarily composed of?

Nutrients, gases, and other essential substances for life.

Define thermodynamics.

A branch of physics that studies energy transfers and transformations.

What are open systems?

Systems that allow the exchange of both energy and matter with their surroundings.

What is the primary energy source for most ecosystems?

Sunlight.

What is chemosynthesis?

The process by which specialized bacteria extract energy from inorganic compounds.

What role do decomposers play in ecosystems?

They break down dead organisms and organic matter, returning nutrients to the environment.

Differentiate between saprotrophs and detritivores.

Saprotrophs obtain nutrients through external digestion; detritivores obtain nutrients via internal digestion.

What are autotrophs?

Organisms that use external energy sources to synthesize carbon compounds from simple inorganic substances.

What is the process of carbon fixation?

The conversion of inorganic carbon (CO₂) into organic compounds by autotrophs.

Describe the flow of energy in a food chain.

Energy is transferred from producers to primary consumers and then to higher trophic levels through feeding relationships.

How is secondary production defined?

The rate at which consumers accumulate carbon compounds in their own biomass through assimilation.

What is primary production?

The rate at which producers accumulate carbon compounds in their biomass.

How do ecosystems act as carbon sinks?

Ecosystems absorb more CO₂ through photosynthesis than they release through respiration.

What is the Keeling Curve?

A graph that displays the concentration of carbon dioxide (CO₂) in Earth’s atmosphere over time.

What is the significance of the relationship between photosynthesis and respiration?

Photosynthesis produces oxygen necessary for aerobic respiration, while respiration releases CO₂ needed for photosynthesis.

What happens during the combustion of fossil fuels?

It releases large amounts of CO₂ into the atmosphere, significantly altering the carbon cycle.