1. Energy in Ecosystems
Key Area 3.4

2. I understand how animal and plant species depend on each other and how living things are adapted for survival. I can predict the impact of population growth and natural hazards on biodiversity. SCN 4-01a

3. Key Area 4 Learning Outcomes
Glue learning outcomes into your notebook

4. Starter Activity: On a show me board
Choose an organism and state where it gets its energy from.
Pupils should have prior KU from S2 Biodiversity topic about food chains.

5. Energy in Ecosystems
Learning Intention: Describe and explain what happens to the flow of energy in an ecosystem.
Success Criteria:
Construct a food chain
Describe the path of energy flow in a food chain
Explain how much energy is lost from a food chain
Explain how energy is lost from a food chain

6. Skills for life, learning and work: Research skills
Literacy, Numeracy, HWB:
I can make notes and organise them to develop my thinking, help retain and recall information, explore issues and create new texts, using my own words as appropriate.
LIT 3-15a / LIT 4-15a
Using what I know about the features of different types of texts, I can find, select, sort, summarise, link and use information from different sources.
LIT 3-14a / LIT 4-14a
Skills for life, learning and work:
Research skills
Understanding of new scientific terms
Becoming confident in new biological terms

7. Revision from key area 3.1- Ecosystems
Teacher notes
This four-stage animated food chain shows a simple feeding relationship within an ecosystem. It can be used to introduce the topic and start students thinking about energy losses in the food chain. The direction of the arrow indicates the direction of energy flow.
See the ‘Photosynthesis’ presentation for more information about photosynthesis.

8. Energy Flow in Ecosystems
Watch the following video clips:
Energy in Ecosystems Clip 1
Energy in Ecosystems Clip 2
Answer these questions on a Show Me Board:
How much energy is lost at each level of a food chain?
How is this energy lost?

9. Teacher notes
This activity provides illustrated information about how energy is lost in food chains. It could be used as an introduction to this topic or for revision purposes.

10. Energy Flow in Ecosystems- revision of key area 3.1
At each level in a food chain, the majority of energy is lost as:
Heat
Movement
Undigested materials

11. Energy Flow in Ecosystems
As so much energy is lost, only a small quantity is used for the growth of that organism.
This energy is therefore carried to the next level of the food chain.

12. Energy in Ecosystems
Learning Intention: Describe and explain what happens to the flow of energy in an ecosystem.
Success Criteria:
Construct a food chain
Describe the path of energy flow in a food chain
Explain how much energy is lost from a food chain
Explain how energy is lost from a food chain

13. Energy in Ecosystems
Only a small quantity of energy is transferred from one level of the food chain to the next.

14. Right’s Respecting School: UN Convention of the Right’s of a Child
Article 13: Every child must be free to say what they think and to seek and receive all kinds of information, as long as it is within the law.
Research hwk- causes and types of diabetes, what it is etc.

15. What does a food chain always start with?
Starter Activity:
In groups, talk over the answers to these questions, we will then discuss as a class:
What does a food chain always start with?
What does the arrow in a food chain represent?
How much energy is passed on to the next level in a food chain?
Give an example of how energy is lost at each stage in a food chain.
Pupils should have prior KU from S2 Biodiversity topic about food chains.

16. Pyramids of energy and numbers.
Learning Intention: Show the energy and numbers of organisms within a food chain as a diagram.
Success Criteria:
Define ‘Pyramid of energy’ and construct one from data about a food chain.
Define ‘Pyramid of number’ and construct one from data about a food chain.

17. Why aren’t food chains very long?
This tiger is a top predator; the final level in a food chain.
Most food chains only contain four or five species, why is this?
Photo credit: © 2007 Jupiterimages Corporation
Energy is lost at all levels in food chains.
Animals at the top of a long food chain would not get enough energy to survive.

18. What are pyramids of numbers?
Pyramids of numbers are a way of representing food chains.
They record the number of organisms at each feeding level in a specified area.
What are the problems of representing food chains in pyramids of numbers?

19. Pyramids of numbers
The length of each bar represents the number of organisms at each feeding level.
They show the number of each organism at each stage of a food chain.
Glue in your regular pyramid of numbers diagram

20. A pyramid of numbers may be an irregular shape, because the producer may be one large tree, supporting many organisms.
There are some exceptions to the classic pyramid shape. These pyramids are said to be irregular.
Some food chains have a single large producer e.g. a tree.
Another exception is when a parasite is the top carnivore in the food chain:
Glue in your irregular pyramid of numbers diagram

21. Pyramids of energy
In a pyramid of energy, the length of each bar represents the volume of energy available– at each feeding level. As energy is always lost at each level, it will always be a regular pyramid shape.
Glue in your pyramid of energy diagram

22. Pyramids Task
Draw and label each type of pyramid numbers and energy for each food chain:
Oak tree  Caterpillar  Blackbird  Fox
Green algae  Water flea  Tadpole  Trout
Grass  Aphid  Ladybird  Robin
Lettuce  Vole  Fox  Fleas

23. Pyramids of energy and numbers.
Learning Intention: Show the energy and numbers of organisms within a food chain as a diagram.
Success Criteria:
Define ‘Pyramid of energy’ and construct one from data about a food chain.
Define ‘Pyramid of number’ and construct one from data about a food chain.

24. Right’s Respecting School:
UN Convention of the Right’s of a Child
Article 3: The best interests of the child must be a top priority in all things that affect children.

25. Skills for life, learning and work:
Literacy, Numeracy, HWB:
I make full use of and value the opportunities I am given to improve and manage my learning and, in turn, I can help to encourage learning and confidence in others.
HWB 3-11a / HWB 4-11a
When I engage with others I can make a relevant contribution, ensure that everyone has an opportunity to contribute and encourage them to take account of others’ points of view or alternative solutions.
I can respond in ways appropriate to my role, exploring and expanding on contributions to reflect on, clarify or adapt thinking.
LIT 4-02a
Skills for life, learning and work:
Applying knowledge of new scientific terms
Problem solving
Improve confidence

26. Key Area 3.4 Energy in Ecosystems
Past Paper Practice
National 5
Key Area 3.4
Energy in Ecosystems
Total Marks /

27. Question 1
1 mark

28. Question 2
1 marks

29. Question 3
1 mark

30. Question 4
1 mark

31. Question 5
1 mark

32. Question 6
1 mark

33. Key Area 3.4 Energy in Ecosystems
Past Paper Practice
National 5
Key Area 3.4
Energy in Ecosystems
Total Marks /

34. Question 1
1 mark

35. Question 2 L
2 marks

36. Question 3
9700
1 mark

37. Heat/movement/undigested material
Question 4
Heat/movement/undigested material
1 mark

38. Question 5
1 mark

39. Question 6
1 mark