The Antarctic Ecosystem Part 1

Summary

The Antarctic ecosystem is a relatively simple system where living organisms interact with each other and their non-living environment. It serves as a clear example of how ecosystems function, with energy flowing through feeding relationships and nutrients being recycled.

• Ecosystem — A community of living organisms interacting with each other and their environment.
  Example: The Antarctic ecosystem includes penguins, seals, and krill interacting with ice and ocean currents.
• Biotic Factors — Living components of an ecosystem.
  Example: Penguins, seals, whales, krill, and phytoplankton in Antarctica.
• Abiotic Factors — Non-living components of an ecosystem.
  Example: Temperature, ice coverage, sunlight, wind, and ocean currents in Antarctica.
• Producer — Organisms that make their own food through photosynthesis.
  Example: Phytoplankton and algae in the Antarctic waters.
• Consumer — Organisms that eat other organisms for energy.
  Example: Krill, penguins, seals, and whales in the Antarctic food web.
• Keystone Species — A species with a disproportionately large effect on its ecosystem.
  Example: Krill in the Antarctic ecosystem.
• Nutrient Cycling — Movement of nutrients between living organisms and the non-living environment.
  Example: Nutrients from penguin guano returning to the ocean to fertilize phytoplankton.
• Interdependence — How organisms depend on each other for survival.
  Example: The reliance of Antarctic predators on krill populations.

Exam Tips

Key Definitions to Remember

• Ecosystem
• Biotic Factors
• Abiotic Factors
• Producer
• Consumer
• Keystone Species
• Nutrient Cycling
• Interdependence

Common Confusions

• Mixing up biotic and abiotic factors
• Confusing food chains with food webs

Typical Exam Questions

• What is a keystone species?
  A species that has a disproportionately large effect on its ecosystem.
• How do abiotic factors affect the Antarctic ecosystem?
  They influence the survival and distribution of organisms.
• Explain the role of krill in the Antarctic food web.
  Krill transfer energy from producers to higher trophic levels and are a central food source for many predators.

What Examiners Usually Test

• Ability to distinguish between biotic and abiotic factors
• Understanding of energy flow in food chains and webs
• The impact of changes in one component on the entire ecosystem
• The role of keystone species like krill in maintaining ecosystem stability