C4.2 Transfer of energy and matter

1. Ecosystems: open systems where energy and matter can enter and exit. Definitions of terms: Population, Ecosystem, Community, Species, Habitat

2. Sun as principal source of energy sustaining ecosystems

3. Flow of chemical energy through food chains + keystone species

4. Apply: Construction of food chains and food webs to represent feeding relationships

5. Carbon compounds in dead organic matter are the supply of energy to decomposers

6. Autotrophs: organisms that use external energy sources to synthesise carbon compounds from simple inorganic substances

7. Light is the external energy source in photoautotrophs, oxidation reactions are the energy source in chemoautotrophs

8. Heterotrophs - organisms which use carbon compounds obtained from other organisms

9. Release of energy in both photo/heterotrophs by oxidation of carbon compounds during respiration

10. Classification of organisms into trophic levels, bioaccumulation and magnification

11. Apply: Construction of energy pyramids

12. Reduction in energy availability in each successive stage in food chains due to large energy losses in between trophic levels

Heat loss, undigested food and faeces, uneaten parts, organisms which are not preyed upon

13. Heat loss in both auto and heterotrophs: conversion of chemical energy to heat in respiration

14. Restrictions on number of trophic levels in ecosystems due to energy losses

15. Primary production: accumulation of carbon compounds in biomass by autotrophs

16. Secondary production: accumulation of C compounds in biomass by heterotrophs

17. *DRAW: Constructing carbon cycle diagrams

18. Ecosystems: as carbon sinks and sources

19. Release of CO2 into atmosphere during combustion of biomass, peat, coal, oil, natural gas

20. Analysis of Keeling Curve (photosynthesis, respiration and combustion)

21. Aerobic respiration depends on atmospheric O2 produced by photosynthesis, Photosynthesis depends on atmospheric CO2 produced by respiration

22. Recycling of all chemical elements required by living organisms in ecosystems