GCSE Biology Ecosystems Revision Notes

• 1An ecosystem consists of living organisms (plants, animals, microorganisms) and their physical environment (soil, water, climate).
• 2Energy flows through ecosystems, primarily through food chains and food webs, starting from producers to consumers and decomposers.
• 3Biogeochemical cycles, such as the water cycle and carbon cycle, are essential for recycling nutrients in ecosystems.
• 4Biodiversity within ecosystems contributes to resilience and stability, allowing ecosystems to adapt to changes.
• 5Human activities can impact ecosystems through pollution, deforestation, and climate change, leading to loss of biodiversity.

An ecosystem is a place where living things, like plants and animals, interact with each other and their surroundings, like water and soil. These interactions create a balanced environment where energy and nutrients flow. For example, plants use sunlight to grow, animals eat the plants, and when they die, decomposers break them down, returning nutrients to the soil.