MONITORING THE ENVIRONMENT ENERGY FLOW NUTRIENT TRANSFER

1. MONITORING THE ENVIRONMENTENERGY FLOW NUTRIENT TRANSFER

2. Energy Flow

3. Learning Outcomes • understand that radiation from the Sun is the source of energy for most ecosystems / communities of living organisms and that green plants, and other photosynthetic organisms such as algae, capture a small percentage of the solar energy which reaches them.

4. Food Chains • Food chains are one way of showing how organisms interact. Grass Rabbit  Fox • The arrows represent the transfer of energy between organisms.

5. Food Chains • Plants are producers because they make their own food • Animals are consumers because they eat food to obtain energy.

6. Consumers and Decomposers • There are 3 types of consumer • Herbivores eat plants • Carnivores eat other animals • Omnivores eat plants and animals • Organisms that breakdown dead plants and animals are called decomposers • e.g. fungi and bacteria

7. Producer  primary  secondary  tertiary consumer consumer consumer • Each feeding level is known as a trophic level

8. Energy in the Ecosystem • The sun is the main source of energy for food chains • Photosynthetic organisms capture a small percentage of the solar energy which reaches them and convert this into chemical energy. • This chemical energy is then available to other organisms.

9. Light energy available to the plant • Of the 100% solar energy reaching the Earth only some is trapped by chlorophyll • What happens to the rest? • Reflected by clouds or dust in the air • Reflected by plants • Does not fall on leaves • Wrong wavelength for chlorophyll to trap • Pass through leaves

10. Energy Flow through an ecosystem • Energy is transferred from one organism to another. • This is shown in food chains and food webs • Energy given out by organisms is lost to the environment.

11. Pupil ActivityFood Chains and energy in living systems • Colour in the handout • Answer the questions below in full sentences • In a cool, wet summer the hedgerow insect population is low. Why will fewer young weasels be born that spring survive? • Simple food chains of the type shown, are uncommon, why? • Why does the amount of energy flowing through the food chain fall so much between each level?

12. Prep: Food Chains and Energy Flow • Read all the information provided • Answer questions 1 – 7 • This is due in on Wednesday 18th May 2011

13. Learning Outcomes • Investigate data about food chains and food webs and understand that they show the transfer of energy between organisms and involve producers; first, second and third stage consumers; herbivores and carnivores.

14. Energy Flow – Progress question • What is the source of energy for ecosystems? • How does energy from that source become available to a predator like a tiger?

15. Food chains show the flow of energy through an ecosystem

16. Plants are at the start of every food chain

17. Food Webs • If food chains in a habitat are linked, they form a FOOD WEB.

18. Food web for a single tree

19. Changing Food Webs • Look at the two examples of ecosystems given. • For each question give a suggestion of what might happen to the populations of organisms and explain why you think this.

20. Changing food webs

21. Changing food webs

22. Food Webs • Food webs are easily unbalanced if one population of organisms in the web disappears due to: • Over-predation or hunting • Disease • Pollution • Use of pesticides • Lack of food • emigration

23. Past Paper Question (grade B) • Answer the question on Sandeels • 4. (a) • decrease the numbers (of sandeels) [1] • sandeels are eaten by herring [1] • herring compete with sandeels for (animal) plankton/feed on plankton [1]

24. (b) 3 effects are looked for in the answer from: • herring compete with birds for sandeels/reduce number of sandeels; • sandeels do not have enough food / (animal) plankton; • rise in sea temp (global warming) affect plankton distribution or numbers; • fishing for sandeels; • Not enough food for birds as numbers of sandeels dropping. • (not: ref. bird breeding rate unqual./ref. herring killing sandeels)

25. (c) quotas for sandeel fisheries / sandeel fishing ban or protected species/ marine or nature reserves [1] • (not: captive breeding/increase number of seals/fishing ban unqual.)

26. Learning Outcomes • understand that at each stage in the food chain energy is used in repair and in the maintenance and growth of cells whilst energy is lost in waste materials and as heat during respiration.

27. Energy Loss in a food chain • Energy is lost at each level in the food chain • Respiration (lost as heat) • Used up in movement • Maintaining constant body temperature • Faeces and urine (lost as heat) • Some material not being eaten by the consumer

28. Energy loss in a food chain • 90% of energy is lost at each level in a food chain Tree  aphid  ladybird  little bird  big bird 100 10 1 0.1 0.01 Energy units • In long food chains, very little energy is left for the top carnivore • In short food chain, less energy is lost.

29. Energy losses from an animal • Herbivore

30. Energy losses from an animal • Carnivore

31. Shortening the food chain • The fewer the trophic levels, the less food energy is lost so the more food is available to consumers.

32. Shortening the food chain • Energy transfer between producers and consumers is inefficient because: • Some plant material is not digested and passes out of the herbivore body as faeces • The herbivore uses energy to stay alive • When the herbivore dies, its body represents “locked up” energy, which transfers to decomposers

33. Pupil Activity • Practice question on food chains and energy flow.

34. Learning Outcome • use data to construct and interpret pyramids of numbers and biomass.

35. Food Pyramids • Each trophic level is represented by a horizontal bar • The width of the bar represents • The number of organisms • The amount of biomass • The base of the pyramid represents the producer • The second level is the primary consumer, etc

36. Pyramids of number • This represents the relative number of each type of organism at each trophic level. • Draw a pyramid of number for each of the three food chains below: • Grass  antelope  lion • Oak tree  caterpillar  blue tits  owl  fleas • Rose bush  aphid  ladybird  blackbird

37. Pyramids of number • Pyramids of number can be inverted as they do not take into account the size of the organism. • Pyramids of Biomass take into account the number of organisms and their size. • Pyramids of biomass are never inverted.

38. Pyramids of Biomass • This represents the amount of living material (biomass) at each level. • Draw a pyramid of biomass for each of the three food chains below: Grass  antelope  lion Oak tree  caterpillar  blue tits  owl  fleas Rose bush  aphid  ladybird  blackbird

39. Practice Questions on Pyramids • Collect • a question sheet • A sheet of A4 paper • Graph paper

40. Nutrient Transfer

41. Learning Outcomes • understand that carbon is constantly cycled in nature by the carbon cycle via photosynthesis which incorporates it and respiration which releases it.

42. Nutrient Cycling • Materials are returned to the environment in waste materials or when living things die and decay. • We say that they are recycled. • This decay is caused by organisms: • Detritivores e.g. worms • Decomposers e.g. bacteria and fungi • These release enzymes which are adapted to breakdown material

43. For decay to be successful the following conditions are required. • Oxygen – for respiration • Warmth – bacteria will reproduce more quickly, increasing the number of decomposers. • Water • For normal life processes • To secrete solutions of digestive enzymes • To absorb the products of digestion

44. Most living matter is made up of just 6 elements; carbon, hydrogen, oxygen, nitrogen, phosphorous and sulphur. • Living things need these elements to make proteins, carbohydrates and fats.

45. The carbon cycle Carbon dioxide In the air (CO2) photosynthesis respiration Combustion (burning) feeding Carbon compounds in plants Carbon compunds in animals Fossil fuels Coal, oil, gas, peat decay

46. Past Paper Questions • 2 • (a) • (i) Two from: leaves, grass, twigs [1] • (ii) Compost [1] • (iii) Improve soil (not: fertiliser) [1] • (b) • (i) Bacteria/fungi (not: mould) [1] • (ii) Oxygen [1] • (iii) heat from respiration

47. Past Paper Questions • 5 • (a) A burning [1] B photosynthesis [1] • (b) • (i) Increase/rise [1] • (ii) Global warming / acid rain (spec) / accept greenhouse effect [1] (not: pollution/greenhouse gas/specific examples e.g. melting ice caps/ increase in temperature)

48. Past Paper Questions • 5. • (a) (i) Clockwise – burning, respiration, feeding, photosynthesis [4 × 1] • (b) bacteria / fungi / decomposers [1] (not: microbes/worms) • (c) deforestation / increase burning fossil fuels / increase in traffic / increase in power stations [1] (not: cutting down trees) • (d) • (i) killing fish / trees/ tops of pine trees turn yellow [1] • (ii) lung disease [1

49. Past Paper Questions • 4 • (a) • bacteria and fungi 1 mark each [2] • (allow: decomposers for 1 mark, no mark for bacteria/fungi as well) • (b) • (i) • Respiration 2 [1] • Combustion 1 [1] • Photosynthesis 3 [1] • (ii) feeding/ingestion [1] (not: digestion/food chain/nutrition)

50. Learning outcomes • know that microorganisms, bacteria and fungi, feed on waste materials from organisms and that when plants and animals die their bodies are broken down by microorganisms bringing about decay. These microorganisms respire and release carbon dioxide into the atmosphere. • Understand what happens when decay is prevented. Burning fossil fuels releases carbon dioxide.