Ecosystems Food Webs Energy exchange

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Ecosystems Food WebsEnergy exchange
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Questions

• Which of the following would represent a good
  investigative experiment testing for affects of a
  drug on pregnancy?
• 1) A pregnant mouse given 1 ml of a drug and a
  non-pregnant mouse given 1 ml of a placebo.
• 2) A pregnant mouse given 1 ml of a drug and a
  non-pregnant mouse given 1 ml of a drug.
• 3) A pregnant mouse given 1 ml of a placebo and
  another pregnant mouse given 1 ml of a drug.
• 4) A non- pregnant mouse given 1 ml of a drug and
  a non-pregnant mouse given 1 ml of a placebo.

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Ecosystems

• On a blue index card Write down a definition of
  an ecosystem. Time limit is 2 minute.
• Pair-Share your definition and then on a green
  index card write a shared definition between you
  and your partner.

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Ecosystems

• A community of organisms (i.e. plants and
  animals) living together with their environment
  (non-living aspects), functioning as a unit.

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Energy Flow, NutrientCycling, Feeding
Relationships

• Nutrients (purple) neither enter nor leave cycle
• Energy (yellow) is not recycled
• Captured by producers
• Transferred through consumers (red)
• Each transfer loses energy (orange)

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Primary Productivity Photosynthesis
O2 releasedto air
Energyfromsunlight

• Life uses lt 0.03 of the sun's incident energy
• Most is lost as heat from respiration

CO2 absorbedfrom air
Sugarsynthesized
Growth
Photosynthesis
H2O absorbedfrom soil
Mineralsabsorbedfrom soil
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Colored index cards

• Use a purple index card. It has been said that
  all flesh is grass. Explain in a couple of
  sentences why that statement could be true.

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Food Chains

• (a) A simple terrestrial food chain.
• (b) A simple marine food chain.
• 10 law determinesthe population sizeof each
  trophic level
• More organisms at lower trophic levels

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A Food Web

• Simple food web on a short-grass prairie
• Numbers represent trophic levels

1producer 2primary consumer 3secondary consu
mer 4tertiary consumer
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Energy Transfer and Loss
Heat
SecondaryConsumer
PrimaryConsumer
Producer
Heat
DetritusFeeders
Chemicals
Heat
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Energy transfer

• Only 10 of the total energy is used at each
  level
• In other words if a producer has 100 calories of
  useable energy then an herbivore has only 10
  calories of useable energy and a carnivore only
  has 1 calorie

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An Energy Pyramid for aPrairie Ecosystem The
10 Law
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Food web exercise

• Grab a name tag
• Wait for instructions
• Producers candy
• Dinoflagellatestootsie rolls
• Green algaebutter toffee
• Diatomshard candy
• Brown algaebutterscotches
• Consumers
• PrimaryTurquoise
• Secondarydark green
• TertiaryFluorescent green
• Primary pickup as many candy as possible in 30
  seconds
• Secondary tag as many producers as possible
• Tertiary tag as many secondary

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Food web exercise

• Goal ?
• 10 rule
• Modify for fourth graders?

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Questions

• Which of the following statements best describes
  the movements of energy through an ecosystem?
• 1. Energy flow through
• 2. Energy cycles
• 3. Energy increases
• 4. Energy recycles

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Questions

• The amount of life that can be supported by an
  ecosystem is determined by the
• 1) Efficiency of the consumers
• 2) Number of producers and their efficiency
• 3) Number of heterotrophs and their efficiency
• 4) Number of decomposers and their efficiency

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Questions

• If a wolf eats a rodent that ate a smaller insect
  that ate a plant, the wolf would be a(n)
• 1) primary consumers
• 2) decomposers
• 3) producers
• 4) secondary consumers
• 5) tertiary consumers