1. Ecosystems perform essential functions that sustain life on Earth.
  2. Two primary functions of ecosystems are energy flow and nutrient cycling.
  3. Energy flow refers to the transfer of energy through different trophic levels in an ecosystem.
  4. Nutrient cycling involves the recycling of elements like carbon, nitrogen, and phosphorus within the ecosystem.
  5. Energy flow in an ecosystem is unidirectional, moving from the sun to producers and then to consumers and decomposers.
  6. Producers capture solar energy through photosynthesis and convert it into chemical energy.
  7. The energy captured by producers is called gross primary productivity (GPP).
  8. Net primary productivity (NPP) is the energy available to consumers after producers use some for respiration.
  9. Consumers obtain energy by feeding on producers or other consumers.
  10. Decomposers break down organic matter, releasing nutrients back into the ecosystem.
  11. The trophic levels in an ecosystem are producers, primary consumers, secondary consumers, tertiary consumers, and decomposers.
  12. Energy transfer between trophic levels is inefficient, with only about 10% of energy passed to the next level.
  13. This is known as the 10% law of energy transfer, proposed by Raymond Lindeman.
  14. The loss of energy limits the number of trophic levels in an ecosystem.
  15. The energy flow can be represented using food chains and food webs.
  16. A food chain is a linear sequence showing energy transfer from one organism to another.
  17. A food web is a complex network of interconnected food chains in an ecosystem.
  18. Nutrient cycling, also known as biogeochemical cycling, maintains the balance of essential elements in ecosystems.
  19. The carbon cycle involves the exchange of carbon among the atmosphere, organisms, and soil.
  20. Photosynthesis and respiration are key processes in the carbon cycle.
  21. The nitrogen cycle converts nitrogen from the atmosphere into forms usable by plants and animals.
  22. Nitrogen fixation is carried out by certain bacteria, converting atmospheric nitrogen into ammonia.
  23. The phosphorus cycle moves phosphorus through rocks, water, soil, and living organisms.
  24. The phosphorus cycle lacks a significant atmospheric component, unlike the carbon and nitrogen cycles.
  25. The water cycle, or hydrological cycle, involves the movement of water through evaporation, condensation, and precipitation.
  26. Nutrient cycling ensures the availability of essential nutrients for plants, animals, and microorganisms.
  27. The interaction between energy flow and nutrient cycling drives ecosystem productivity.
  28. Human activities, such as deforestation and pollution, disrupt energy flow and nutrient cycling.
  29. Eutrophication is caused by excessive nutrient runoff, leading to algal blooms and oxygen depletion in water bodies.
  30. Climate change impacts energy flow and nutrient cycling by altering ecosystem dynamics.
  31. The efficiency of energy flow and nutrient cycling determines the health of an ecosystem.
  32. Conservation efforts aim to restore balance in ecosystems by addressing these key functions.
  33. Understanding energy flow and nutrient cycling helps in sustainable resource management.
  34. Ecological pyramids represent energy, biomass, or organism numbers across trophic levels.
  35. An energy pyramid illustrates the reduction of energy at successive trophic levels.
  36. A biomass pyramid shows the total mass of living organisms at each trophic level.
  37. A number pyramid represents the number of organisms at each trophic level.
  38. Energy flow and nutrient cycling are influenced by climatic and geological factors.
  39. The efficiency of energy flow is higher in ecosystems with shorter food chains.
  40. Ecosystems with diverse biodiversity tend to have more stable energy flow and nutrient cycles.
  41. Decomposers play a vital role in maintaining nutrient cycling by breaking down organic matter.
  42. Efforts to reduce waste and recycle materials align with the principles of nutrient cycling.
  43. Energy flow and nutrient cycling are interconnected, supporting life processes in ecosystems.
  44. Disruptions in these processes can lead to ecosystem degradation and biodiversity loss.
  45. The study of these functions is crucial for addressing environmental challenges and promoting sustainability.

Questions

  1. What is energy flow in an ecosystem?
  2. What is the primary source of energy for most ecosystems?
  3. How does energy transfer between trophic levels?
  4. Why is energy flow in an ecosystem unidirectional?
  5. What percentage of energy is typically transferred to the next trophic level?
  6. What happens to energy that is not transferred to the next trophic level?
  7. What is nutrient cycling in an ecosystem?
  8. Which process is a part of the carbon cycle?
  9. How is nitrogen returned to the atmosphere in the nitrogen cycle?
  10. Which of the following is part of the water cycle?
  11. What is the role of decomposers in nutrient cycling?
  12. Which organisms are responsible for nitrogen fixation?
  13. What happens to nutrients in a closed ecosystem?
  14. Why is energy flow in an ecosystem considered inefficient?
  15. What is the primary reservoir of carbon in the biosphere?
  16. How does phosphorus enter ecosystems?
  17. What is the key role of plants in nutrient cycling?
  18. What is the term for organisms that use sunlight to produce energy?
  19. Which process in the water cycle involves the loss of water from plants?
  20. What is the role of the sun in energy flow?
  21. How does energy flow differ from nutrient cycling in an ecosystem?
  22. What is the main pathway for carbon to enter the food chain?
  23. Which trophic level contains the most energy in an ecosystem?
  24. What is the role of respiration in the carbon cycle?
  25. Why is phosphorus a limiting nutrient in ecosystems?
  26. What happens during biological magnification?
  27. What is the ultimate fate of energy in ecosystems?
  28. What process releases nutrients from dead organisms?
  29. Which element is a key component of amino acids and proteins?
  30. How does human activity most impact the carbon cycle?
  31. Which cycle involves the process of evaporation and precipitation?
  32. What is the function of the nitrogen-fixing bacteria in the nitrogen cycle?
  33. What is the role of primary consumers in energy flow?
  34. How does energy enter most ecosystems?
  35. What is a major pathway for nitrogen to enter ecosystems?
  36. What is the main way phosphorus is lost from the soil?
  37. What is the primary form of energy in ecosystems?
  38. How do fossil fuels impact the carbon cycle?
  39. Why is energy transfer between trophic levels inefficient?
  40. What happens to phosphorus in aquatic ecosystems?
  41. How does energy flow through a food web?
  42. Which process converts sunlight into chemical energy?
  43. What limits the length of food chains?
  44. How do decomposers contribute to energy flow?
  45. What process in the nitrogen cycle involves converting ammonia to nitrates?