OCRBiologyExam Board Revision

OCR Biology Ecosystems Revision Notes

Master OCR Biology Ecosystems using simple revision notes, key facts and practice questions — all generated by AI for your exam.

Ecosystems are dynamic systems composed of living organisms (biotic factors) and their physical environment (abiotic factors). They involve interactions between different species and their environment, which influence the flow of energy and matter.

Key Concepts

  • 1Ecosystems consist of biotic and abiotic components.
  • 2Energy flows through ecosystems via food chains and food webs.
  • 3Nutrient cycling is essential for ecosystem sustainability.
  • 4Biodiversity contributes to ecosystem resilience.
  • 5Human activities can disrupt ecosystems and their functions.

Simple Explanation

An ecosystem is a community of living things, like plants and animals, interacting with each other and their environment, such as soil and water. They rely on each other for food, shelter, and nutrients. Changes in one part of the ecosystem can affect the whole system, making it important to keep ecosystems healthy.

Memory Trick

Remember 'B.E.N.E.F.I.T' for Ecosystem: Biodiversity, Energy flow, Nutrient cycling, Ecosystem services, Functionality, Interactions, and Trophic levels.

Flashcards

Question1 / 5

What are the two main components of an ecosystem?

Tap to reveal answer

Exam Questions

Describe and explain the role of decomposers in an ecosystem. [6 marks]

6 marks
View mark scheme hint

Mention their function in nutrient cycling, breaking down organic matter, and supporting plant growth.

Explain how energy is transferred through a food chain. [4 marks]

4 marks
View mark scheme hint

Discuss producers, consumers, and energy loss at each trophic level.

What is meant by biodiversity? [2 marks]

2 marks
View mark scheme hint

Define biodiversity and its importance in ecosystems.

Practice Quiz

Question 1 of 5Score: 0

What is the primary source of energy for most ecosystems?

Need custom study material?

Paste your own notes into StudyMate AI and instantly generate summaries, flashcards and quizzes tailored to your content.

Study Your Own Notes