1. BIOZONE: P. 168-171,174 Text: P. 752-753 Digital Text:
Sponge: Set up Cornell Notes on pg. 91
Topic: 4.2 Food Chains and Webs
Essential Question: Draw three food chains, each with at least 3 linkages (4 organisms)-words only
BIOZONE: P ,174
4.2 Food Chains and webs
Draw three food chains, each with at least 3 linkages- words only
Key Vocabulary:
Food Chains
Food Webs
Trophic Levels:
Primary/Secondary/Tertiary/
Quaternary Consumer
Text: P
Digital Text:

2. P. 90 Trophic Level Pyramid In class: Construct a food web
Build-Your-Own Food Web

3. Understanding
Most ecosystems rely on a supply of energy from sunlight

4. The Importance of Sunlight
All life you see around you on Earth’s surface relies either directly or indirectly on sunlight

5. Understanding
Light energy is converted to chemical energy in carbon compounds by photosynthesis

6. The role of photosynthesis
Remember photosynthesis:
Takes simple inorganic CO₂ and convert it into energy-rich sugar C₆H₁₂O₆
Light energy from sun is being converted into chemical energy (food)

7. The role of photosynthesis
Chemical energy refers to the fact that organic compounds such as carbs, proteins, and lipids are rich in energy
Can be measured by calories or kilocalories
One way to release the chemical energy from organic compounds is to digest the food

8. Understanding
Chemical energy in carbon compounds flows through food chains by means of feeding

9. Food Chains
By feeding on producers, consumers can utilize the chemical energy to grow and stay healthy

10. Food Chains
A food chain is a model that shows a sequence of feeding relationships and energy flow between species
A food chain follows the connection between one producer and a single chain of consumers within an ecosystem.
DESERT COTTONTAIL
GRAMA GRASS
HARRIS’S HAWK
*The direction of the arrow shows the direction of energy flow

11. Draw on top of P. 90- include examples
Trophic levels refer to an organism’s position in a food chain.
Classify organisms by their feeding relationships with the other organisms in the same ecosystem
T5= Quaternary Consumer
T4= Tertiary Consumer
T3= Secondary Consumers
T2= Primary Consumers herbivores
T1= Primary Producers plants
……C a r n i v o r e s…….
Draw on top of P. 90- include examples

12. Understanding
Most species occupy different trophic levels in multiple food chains

13. Organisms can fit into more than one tropic level!
Ex: A common seal is in T3 when it feeds on Grey Mullet
But will be in T4 when it feeds on lobster T4 T3 T3 T2 T2 T1 T1

14. Understanding
A food web shows all the possible food chains in a community

15. An interconnecting series of food chains.
A food web emphasizes complicated feeding relationships and energy flow in an ecosystem.
An interconnecting series of food chains.
Since organisms usually eat more than one type of food, a simple food chain does not tell the whole story
ENERGY

16. Arctic Marine Food Web

17. Food Webs m7s

18. Understanding
Energy losses between trophic levels restrict the length of food chains and the biomass of higher trophic levels

19. Energy Levels in Trophic levels
The number of levels is limited by how much energy enters the ecosystem
Energy is lost at each level
So the # of organisms in the chain as well as the quantity of light available at the beginning will determine how long the chain is

20. Determining an organism’s tropic level
In order to determine the tropic level of each organism start with the producer.
Remember: some organisms occupy more than one trophic level or take their food from multiple trophic levels
Algae mosquito larva dragonfly larva fish raccoon
Algae (T1) mosquito larva (T2) dragonfly larva (T3) fish (T4)raccoon (T5)

21. In Class Practice: Construct a Food Web
Algae (plant) is eaten by the mayfly larva
Leaf debris is eaten by the caddis fly larva and the blackfly larva
The mayfly larva, caddis fly larva, and the blackfly larva are eaten by juvenile trout (fish)
The juvenile trout is eaten by the kingfisher (bird)
The mayfly larva is also eaten by the sculpin (fish) and the stonefly larva, all of which are eaten by adult trout (fish)
Please include labels to indicate the tropic level of each organism (T 1-5)
Middle of p. 90
Just use words and arrows

22. T3/

23. All trophic levels must be labeled (T1/T2 etc.) Must have pictures
On the bottom p. 90: Construct a food web containing up to 10 organisms
All trophic levels must be labeled (T1/T2 etc.)
Remember: some organisms occupy more than one trophic level or take their food from multiple trophic levels
Must have pictures

24. Max 12 pgs in PDF FORMAT to G. Classroom
IA—Due MONDAY
MAKE SURE TO INCLUDE A SECTION ON PERSONAL ENGAGEMENT
ADD Candidate # --come see me if you need it
You need to process your data in AT LEAST 2 ways
Make sure every table/graph has a proper title + labels + units and uncertainties
Naming format: Lastname_Firstname_Last4digitsofcandidate#
Max 12 pgs in PDF FORMAT to G. Classroom

25. BIOZONE: P. 172-173 Text: P. 754-756 Digital Text:
Sponge: Set up Cornell Notes on pg. 93
Topic: 4.2 Energy Flow-Pyramids
Essential Question: Why are energy transformations never 100% efficient? Explain and give examples.
BIOZONE: P
Text: P
Digital Text:
4.2-C.2 Energy pyramids
Why are energy transformations never 100% efficient? Explain and give examples.
Key Vocabulary:
Energy Pyramid
Gross production
Net production

26. Energy Pyramid (in class)
Energy Pyramid (from worksheet)

27. Understanding
Energy released from carbon compounds by respiration is used in living organisms and converted to heat

28. Cellular respiration and heat
Inside a grasshopper, chemical energy is used for cellular respiration
Glucose originally produced by the grass is converted into CO² and H₂O
This chemical reaction generates a small amount of heat in each of the g.h.’s cells
Any heat generated by cellular reparation is lost to the environment

29. Cellular respiration and heat
If the grasshopper is eaten, some of the chemical energy in its body (protein) is passed on to the next organism
If the grasshopper dies and is not eaten, detritivores and decomposers will use its available energy

30. Understanding
Living organisms cannot convert heat to other forms of energy

31. Heat cannot be recycled
Law of conservation of energy states that energy cannot be created or destroyed, only converted from one form to another
Photosynthesis:
Light energy  chemical energy
Cellular respiration:
Chemical energy  ATP
Heat (once lost, cannot be used again)
Second law of thermodynamics states that when energy is transferred, a proportion of it is lost as heat energy

32. Understanding
Heat is lost from ecosystems
Guidance:
Understand that there is a continuous but variable supply of energy in the form of sunlight but that the supply of nutrients in an ecosystem is finite and limited

33. Heat cannot be recycled
Heat is “lost” from the ecosystem
It will be passed from one tropic level to the next
If energy cannot be recycled how come we don’t run out of energy????
The sun!
If for some reason the sun stops shining, because it is blocked from Earth by clouds or particles of some sort, then the food chain is affected

34. Energy Loss
Only chemical energy can be used by the next trophic level
Only a small amount of the energy which an organism absorbs is converted into chemical energy
No organism can utilize 100% of the energy present
Typically only 10% of the energy available is used from the previous step in a food chain
90/10 Rule

35. The 10% Rule m46s

36. Pyramid of Energy
A pyramid of energy is used to show how much and how fast energy flows from one trophic level to the next in a community
Each level in the food chain contains much less energy than the level below it

37. Because energy is lost, each level is always smaller than the one before
It would be impossible to have a 3rd trophic level wider than the 2nd because organisms cannot create energy, they can only transfer it (inefficiently)
The energy will eventually flow through decomposers

38. There are also other ways that energy loss occurs

39. Main Reasons for Energy Loss:
Not all of the organism is swallowed as a food source (some parts are abandoned)
Not all of the food swallowed can be absorbed and used in the body
Some organisms will die before being eaten by an organism from the next trophic level
There is considerable loss due to cellular respiration at all trophic levels (movement, maintenance of body temp..)
Eventually ALL the energy which flows through the ecosystem is lost as metabolic heat!

40. Skill
Quantitative representations of energy flow using pyramids of energy
Guidance:
Pyramids of energy should be drawn to scale and should be stepped, not triangular
Use proper terms: primary consumer, secondary…

41. Construct a pyramid of energy
In an ecosystem, the producers make 10,000 kJ m⁻² yr⁻¹ of energy (assume a 90% loss)
Draw an energy pyramid, TRY TO DRAW TO SCALE
Each level should be about 1/10 the level before it
Label all parts
trophic levels (T1-T4/5)
kJ m⁻² yr⁻¹

42. Construct a pyramid of energy
In an ecosystem, the producers make 10,000 kJ m⁻² yr⁻¹ of energy
Tertiary consumers (T4)
Secondary consumers (T3)
Primary consumers (T2)
Primary producers (T1)

43. 5-20% of energy! 80-95% of its energy as heat! Add any missing labels
Each level only gains about
5-20% of energy!
Each level loses up to
80-95% of its energy as heat!
Add any missing labels
Quaternary Consumers
1 J
kJ m⁻² yr⁻¹
kJ m⁻² yr⁻¹
kJ m⁻² yr⁻¹
kJ m⁻² yr⁻¹
kJ m⁻² yr⁻¹

44. Primary Production Gross production – Respiration = Net Production
Gross production: the total amount of energy trapped in the organic matter produced by plants per area per time in kilojoules (kJ) or the amount of light energy that is converted into chemical energy.
Net production: the gross production minus the energy lost through respiration
Gross production – Respiration = Net Production

45. P 92
The gross annual primary productivity of a particular swampland ecosystem is found to be 25,000 kJ m⁻² yr⁻¹ . If respiration by the swampland producers is 15,000 kJ m⁻² yr⁻¹ per year, what is the net annual primary productivity for this ecosystem, in kJ m⁻² yr⁻¹ ?
GPP-R=NPP
GPP= 25,000 kJ m⁻² yr⁻¹
R=15,000 kJ m⁻² yr⁻¹
25,000 kJ m⁻² yr⁻¹ - 15,000 kJ m⁻² yr⁻¹ = 10,000 kJ m⁻² yr⁻¹

46. Construct an energy pyramid: Classwork (pairs)
100
Trophic Level
Energy lost as metabolic heat
Energy lost as detritus 20 65 15
Energy passed to the next trophic level
*Use this set-up to determine the Gross production and net production of the energy pyramid

47. Construct an energy pyramid: Classwork (pairs)
Key:
Start with the #s given!
Then use the “key”
The middle column is your ENERGY
All math is based on this middle column
You will need to add up totals of decomposers +
Respiration is ALL LOSSES added together

48.
– =

50. 38 250
51 000

51.
7 650

53. Total Energy from sun (kJ)
________+________+____________+___________=________
Organic waste
Decomposers
Metabolic Loss
Solar Energy not used
Total Energy from sun (kJ)
Gross production____________________- respiration_______________________=net production__________________

54. Construct an energy pyramid
Bottom P 92
Construct an energy pyramid
Using the data from your worksheet please construct a pyramid of energy
Draw an energy pyramid, TRY TO DRAW TO SCALE
Label all parts (trophic levels, kJ m⁻² yr⁻¹ )
Detritivores/decomposers do not fit into pyramid

55. Construct an energy pyramid
Tertiary Consumers kJ m⁻² yr⁻¹
Secondary Consumers kJ m⁻² yr⁻¹
Primary consumers kJ m⁻² yr⁻¹
Primary Producers kJ m⁻² yr⁻¹

56. BIOZONE: NONE Text: P. 754-756 Digital Text: Essential Question: None.
Sponge: Set up Cornell Notes on pg. 95
Topic: C.2 Energy Pyramids and biomass
Essential Question: None.
BIOZONE: NONE
Text: P
Digital Text:
C.2 Energy Pyramids and Biomass
Key Vocabulary:
Biomass
Feed conversion ratio (FCR)

57. Skill
Comparison of pyramids of energy from different ecosystems

58. Comparing pyramids of energy
When comparing the energy pyramids of two different ecosystems you will notice differences in their efficiency
Notice Cedar Bog has no tertiary consumers
-the lower productivity of the plants makes it unable to support higher levels

59. Comparing pyramids of energy

60. Comparing pyramids of energy
Notice, that organisms at higher and higher trophic levels are increasingly more efficient
Carnivores are the most efficient + +

61. Understandings
The percentage of ingested energy converted to biomass is dependent on the respiration rate

62. Biomass
Biomass: is an estimate of the total (dry) mass of all the organisms within that trophic level
Dry weight of an organism measured in g m⁻² yr⁻¹ (Grams per meter squared per year)
We use dry weight, because the actual weight of the organisms includes a large amount of water (which is not organic matter). Water must be removed by drying.
Three hundred trout are needed to support one man for a year.  The trout, in turn, must consume 90,000 frogs, that must consume 27 million  grasshoppers that live off of 1,000 tons of grass.   -- G. Tyler Miller, Jr., American Chemist (1971)

63. Guidance:
Students should be clear that biomass in terrestrial ecosystems diminishes with energy along food chains due to loss of CO₂ ,H₂O, and other waste products, such as urea

64. Pyramids of biomass
Pyramids of biomass are similar in shape to pyramids of energy
The higher trophic levels have a lower total biomass per unit area of an ecosystem
Like energy, biomass is lost during respiration at each level
Glucose is broken down for energy and converted into CO² and H₂O
CO² and H₂O are excreted and the biomass of glucose is lost

65. Application
Conversion ratio in sustainable food production practices

66. Sustainable food production
The feed conversion ratio (FCR) is a measure of the efficiency of an animal’s ability to convert feed mass into increased body mass (or the desired output)
Shows us how much energy is being lost during the transfer from plants to animals
The “output” is what we want from our animal
Dairy cow milk
Cow/chicken/pig/fish  meat
The lower the FCR, the more energy that is being conserved or gained

67. Sustainable food production
FCR= mass of food eaten body mass gain Ex: 8 kg food = 8 1 kg of weight gain

68. Sustainable food production
Animals with low FCR can be seen to be efficient users of food

69. Sustainable food production
Fish farmers are trying to lower the FCR to 1
The amount of feed would equal the “fish mass” gained 1:1
Therefore nothing would be lost and everything is gained
Tegel Poultry of New Zealand have reported FCR as low as 1.38 on a consistent basis

70. Crash Course: Ecosystem Video (4m-9m)
Take bullets P. 94