Here is an example of a food chain and a pyramid of numbers: plant 15 snail 6 eagle 1 thrush 2 15 plants 6 snails 2 thrushes 1 eagle Notice the producer is always at the bottom of the pyramid Building pyramids Answer the questions below in your books. 1.Draw a food chain for each of the energy transfers below: a.Dandelions (15), rabbits (3), fox (1) b.Cabbages (5), slugs (20), thrushes (5), cat (1) c.Grass (15), rabbit (1), fleas (50) 2.Draw a pyramid of numbers for each of the food chains you have drawn in your books. 3.What happens to the number of organisms as you move up the pyramid? 4.What is an advantage of using a pyramid of numbers? 5.What is a disadvantage of using a pyramid of numbers? 6.What could you use instead of the number of organisms to make your pyramids the right shape? Energy is lost at each level of the food chain – some of the energy is used by the animal or plant. 7.What might the plant or animal use energy for? 8.Write down some of the energy transfers that take place in the animal. Stored chemical energy in the animal or plant is transformed into....?

Instead of using the numbers of each organism, we could use the mass of the organisms in the food chain to build a pyramid. This is called a pyramid of biomass. 9.Draw pyramids of biomass for the food chains below: a.Dandelions (15kg), rabbits (9kg), fox (3kg) b.Cabbages (20kg), slugs (8kg), thrushes (3kg), cat (1kg) c.Grass (15kg), rabbit (6kg), fleas (0.5kg) 10.What happens to the biomass as you move up the pyramid? 11.Why is it better to draw a pyramid of biomass rather than a pyramid of numbers? Bonus numeracy challenge! If the food chains in Question 9 were three times bigger, what would the values be in kilograms? The values for mass in Question 9 are given in kilograms. Convert them all to grams. Bonus literacy challenge! What do you think are the keywords from today’s lesson? How many words can you make using letters from the words ‘pyramids of number’?

Building pyramids 1.Draw a food chain for each of the energy transfers below: a.Dandelions (15), rabbits (3), fox (1) b.Cabbages (5), slugs (20), thrushes (5), cat (1) c.Grass (15), rabbit (1), fleas (50) 2.Draw the pyramids on your squared paper. 3.As you move up the pyramid the number of organisms (individual animals or plants) ___________________________________________________________________ 4.Pyramids of number are better than food chains because __________________________ ________________________________________________________________________ 5.A disadvantage of using pyramids of number is __________________________________ ________________________________________________________________________ 6.Instead of using the number of organisms to make the pyramid of numbers I could use _______________________________________________________________________ 7.An animal or plant might use energy to _______________________________________ 8.Stored chemical energy in an animal or plant could be transformed into: chemical kinetic electrical gravitational potential magnetic nuclear light sound thermal elastic

9.Draw the pyramids of biomass on your squared paper: 10.As you move up the pyramid the biomass ____________________________________ 11.A pyramid of biomass is better than a pyramid of numbers because _______________ ______________________________________________________________________ Literacy challenge: I think the keywords from today’s lesson are Using the letters in the words ‘pyramids of number’ the other words I can make are Numeracy challenge: If the food chains in Question 9 were three times bigger the values in kilograms would be: 15kg dandelions = 9kg rabbits = 3kg fox = 20kg cabbages = 8kg slugs = 3kg thrushes = 1kg cat = 15kg grass = 6kg rabbit = 0.5kg fleas = The mass in the food chains in Question 9 in grams are: 15kg dandelions = 9kg rabbits = 3kg fox = 20kg cabbages = 8kg slugs = 3kg thrushes = 1kg cat = 15kg grass = 6kg rabbit = 0.5kg fleas =