IB Biology C4.2: Transfer of energy and matter (first exams in 2025)

This lesson can be purchased as part of the IB Complete course bundle (first exams 2025) at a heavily discounted price, formed of 40 fully resourced lessons, end of topic exams and student checklists. It can be found here

This PowerPoint contains everything you need to teach the Theme/Unit C4.2 Transfer of energy and matter in the new IB Biology specification.

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This Powerpoint consists of over 80 slides and contains the followings:

All the information the IB have included in the new spec.

Clear diagrams
Student friendly content
Summary videos
Student research tasks
Clearly identified HL and SL content
Student checklist
Exam style questions
Summary

The following content is included:

C4.2.1: Explain the concept of ecosystems as open systems.
C4.2.2: Describe the role of sunlight in ecosystems.
C4.2.3: Outline the flow of energy through food chains and food webs.
C4.2.4: Construct food chains and food webs to represent feeding relationships in a community.
C4.2.5: Describe the role of decomposers in nutrient cycling.
C4.2.6: Distinguish between autotrophic and heterotrophic modes of nutrition.
C4.2.7: Classify organisms into trophic levels based on their position in a food chain or food web.
C4.2.8: Construct an energy pyramid based on ecological data.
C4.2.9: Explain the factors that contribute to energy losses in food chains.
C4.2.10: Outline the causes and consequences of heat dissipation in food chains.
C4.2.11: Describe the factor that restricts the number of trophic levels in a food chain.
C4.2.12: Compare and contrast primary and secondary productivity.
C4.2.13: Explain the factors that affect primary productivity in an ecosystem
C4.2.14: Construct an accurate diagram of the carbon cycle.
C4.2.15: Explain the factors influencing an ecosystem’s capacity to function as a carbon sink or a source.
C4.2.16: Discuss the impact of deforestation on the carbon cycle. 
C4.2.17: Describe how combustion of fossil fuels and biomass affects the carbon cycle.
C4.2.18: Analyse and explain the short-term and long-term trends shown in the Keeling Curve.
C4.2.19: Explain the significance of photosynthesis and aerobic respiration in sustaining life on Earth.
C4.2.20: Explain the importance of cycles of matter in the functioning of ecosystems.