Matter & Energy in Ecosystems Study Guide

Summary of Processes

• Photosynthesis:
  • Reaction: Carbon dioxide + water + energy from sunlight → glucose + oxygen
• Cellular Respiration:
  • Reaction: Oxygen + glucose → carbon dioxide + water + energy released

Vocabulary

• Carbon: An atom found in carbon dioxide and energy storage molecules.
• Carbon Dioxide (CO2): A gas used in photosynthesis and released in cellular respiration.
• Oxygen (O2): A molecule in the air used in cellular respiration.
• Water (H2O): Essential for photosynthesis and produced in cellular respiration.
• Ecosystem: A community of interacting living and nonliving things in an area.
• Closed Ecosystem: An ecosystem that does not exchange matter with its surroundings.
• Bio: A prefix meaning "life".
• Biotic Matter: Matter constituting living and dead organisms within an ecosystem.
• Abiotic Matter: Nonliving matter such as water, rocks, and air.
• Glucose: A sugar produced in photosynthesis and primary energy source for organisms (C6H12O6).
• Energy Storage Molecules: Molecules like glucose used by organisms for energy.
• Producer: Organisms that produce their own energy storage molecules.
• Consumer: Organisms that consume others to obtain energy storage molecules.
  • Primary Consumer: Eats producers.
  • Secondary Consumer: Eats primary consumers.
• Decomposer: Organisms that obtain energy by breaking down dead matter.
• Photosynthesis: The process where green plants use sunlight to produce food.
• Cellular Respiration: The reaction of oxygen and glucose that releases energy.
• Chloroplast: The site of photosynthesis in a cell.
• Mitochondria: The site of cellular respiration in a cell.
• Carbon Cycle: The movement of carbon among plants, animals, and the Earth.

Key Notes

• Carbon Chains: Energy storage molecules contain chains of carbon atoms, making carbon essential for life.

• Role of Producers: Producers are crucial in ecosystems as they supply energy and matter.

• Photosynthesis Details:

  • Producers use environmental CO2 for photosynthesis, absorbing it from the air or water.
  • Sunlight is necessary; more sunlight and CO2 lead to more photosynthesis. No sunlight means no photosynthesis.

• Cellular Respiration Details:

  • All organisms, including decomposers and plants, perform cellular respiration and release CO2.
  • Cellular respiration is necessary for energy production in cells.

Interactions of Photosynthesis and Cellular Respiration

• Photosynthesis and cellular respiration are interconnected processes in ecosystems.
• Both are vital for the carbon cycle, with photosynthesis reducing atmospheric CO2 and cellular respiration adding to it.
• Views of the Carbon Cycle:
  • Emphasizes the flow of carbon through different forms of life and Earth’s systems.