• Open Note (stamp)
▫ Autotrophs (all types)
▫ Heterotrophs (all types)
▫ Food Chains
▫ Food Webs
▫ Producers and Consumers (all trophic levels)
▫ Energy, Biomass, and Numbers Pyramids

• Homework Quiz
• Agenda
• Homework Debrief
• Learning Goal
• String Activity
• Activity Analysis
• Pyramid Activity
• Island Application (Research)
• Homework

• Autotrophs (all types)
• Heterotrophs (all types)
• Food Chains
• Food Webs
• Producers and Consumers (all trophic levels)
• Energy, Biomass, and Numbers Pyramids

• Objective 2.5.F (Energy Models) – I can describe how energy flows through an ecosystem and I can model this with food chains, food webs, and ecological pyramids.

• If possible, find the person with the same word
• Together, hypothesize if/who you consume AND if/who consumes you
▫ There may be multiple answers!
• Approach those other organisms. IFF they agree with your hypothesis, then place a string between you.
▫ Try to keep string untangled
▫ Please do not push through strings

• Based on what we as a class determined, work with your table to draw a food web.
• Determine what each organism is: primary producer, primary consumer, secondary consumer, tertiary consumer, detritivore, or decomposer
▫ It’s okay for you to be incorrect! Take a risk.
• Alligator Lizard, Bacteria, Cricket, Dead Animals, Dead
Leaves, Earthworm, Fox, Fungus, Hawk, Maggots,
Maple Tree Leaves, Millipede, Mushrooms, Pillbugs,
Robin, Rotting Log, Sun

• Detritivores CONSUME detritus
▫ Detritus = dead plants/animals, feces
▫ Millipedes, woodlice, dung flies, slugs, worms, sea stars, sea cucumbers, fiddler crabs
• Decomposers CAN’T EAT. They ABSORB &
BREAK DOWN cells.
▫ Bacteria (dec. meat), fungi (dec. fruits/veggies)

• On panel 1:
▫ Ecological Pyramids
 Graphs of trophic structure
▫ Trophic levels (feeding position)
 Primary producer = autotroph
 Primary consumer = herbivore
 Secondary/Tertiary consumer = omnivore/carnivore

• Panel 2
• Pyramid of Energy
▫ Flow of energy
▫ Lose 90% of energy as heat
 Only 10% of energy available for next trophic level
▫ Base has 100% of energy available

• Panel 3
• Pyramid of Biomass
▫ Biomass per area
▫ Biomass = mass of each individual x number of individuals at each trophic level
▫ g/m 2

• Panel 4
• Pyramid of Numbers
• # of individuals per area
• Large # of producers at base
• Lower # of carnivores at top
▫ (Usually)

• Must have primary producers, primary consumers, secondary consumers, tertiary consumers, and decomposers.
• Must contain autotrophs, herbivores, omnivores, carnivores, and detritivores.
• Create a food web that contains at least 3 organisms at each trophic level + decomposers + detritivores
• Humans do not count!

• Due Wed 4/17 or Thu 4/18
▫ YouTube Video: Biogeochemical Cycles
▫ Homework Quiz: Biogeochemical Cycles
• Homework quiz is open note
• Suggestion: Draw each cycle!!!