V3p lesson 2

Food Chains, Food Webs, and Energy Pyramids

Energy begins with photosynthesis. ​

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Where does energy begin?

Plants use water & carbon dioxide to store energy from the sun in glucose.

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​Organisms that use photosynthesis to make food are called producers/autotrophs​

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​Photosynthesis

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You have to know the formula for photosynthesis.

Multiple Choice

What is another name for producers?

• heterotrophs

• autotrophs

Multiple Select

What is produced as a result of photosynthesis? (Pick 2)

• CO2

• O2

• sugar

• ATP (energy)

All organisms use cellular respiration to turn their food into energy. ​

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Organisms that eat food to get energy are called consumers/heterotrophs​

​You have to know the formula for cellular respiration.

Cellular Respiration

Multiple Select

What is produced as a result of cellular respiration? (Pick 2)

• CO2

• O2

• sugar

• ATP (energy)

Multiple Choice

What is another name for consumers?

• heterotrophs

• autotrophs

Second trophic level

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​Herbivores = only eat plants

Primary consumer

​​Secondary consumer

​Fourth trophic level

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Carnivores or Omnivore

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Predator or Scavenger​

Tertiary consumers

​Third tropic level​

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Carnivores = only eat animals

Omnivores = eat plants and animals​

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Predator or Scavenger​

Multiple Select

Which organism would be found at the second trophic level?

• grass

• lions

• vultures

• antelopes

Multiple Select

Which organisms could be found at the fourth trophic level?

• grass

• lions

• vultures

• antelopes

Multiple Select

Which organism would be found at the first trophic level?

• grass

• lions

• vultures

• antelopes

Open Ended

Why do you think scientists use food chains/ food webs?

Food chains show how energy is transferred from the sun to each trophic level (producer, primary consumer, etc.)

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​Food Chains

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Multiple Choice

What is the difference between food chains and food webs?

• Food chains show a single energy pathways, while food webs show several energy pathways

• Food web show multiple energy pathways, while food chains show only one energy pathway

Food webs show several energy pathways within an ecosystem.

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​Food Webs

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Poll

How much energy do you think is passed to the consumer when they eat food?

• 100%

• 90%

• 75%

• 10%

90% of energy is lost with each trophic level.

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They show:

• the amount of energy decreases for higher consumers

• a large number of producers are needed to support an​ ecosystem.

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​Energy Pyramids

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Pyramid of
numbers
compares the
number of
organisms at
each trophic
level

Pyramid of
biomass
compares the
mass of
biological
organisms at
each trophic
level

Pyramid of
energy
compares
the amount
of energy
passing
through
each trophic
level

Ecological Pyramids

Multiple Choice

How is the majority of energy lost between each trophic level?

• heat

• sleeping

• no energy is lost

Multiple Choice

How much energy is lost from trophic level to trophic level?

• 100%

• 90%

• 75%

• 10%

Multiple Choice

The diagram represents a pyramid of energy in an ecosystem.  Which level would most likely contain organisms that can photosynthesize?

• A
• B
• C
• D

Multiple Choice

Which pyramid of biomass is correct for the food chain shown?

Multiple Choice

If a disease strikes the snakes the hawks will

• increase

• decrease

• not be affected

Multiple Choice

If a disease strikes the snakes the rabbits will

• increase

• decrease

• not be affected

Multiple Choice

All energy on Earth ultimately comes from what source?

• Water

• Sun

• Consumers

• Oxygen

Multiple Choice

What is the role of the fungi?

• autotroph

• heterotroph

• decomposer

• carnivore

• consumer

Multiple Choice

Which organism is the producer (autotroph) of this ecosystem?

• phytoplankton

• krill

• fish

• leopard seal

Multiple Choice

Which organism is the secondary consumer?

• phytoplankton

• krill

• fish

• leopard seal

Multiple Choice

Where do crickets get their energy?

• Cattails
• Marsh Grass
• Grasshoppers
• Shrews

Multiple Choice

Where do crickets get their energy?

• Cattails
• Marsh Grass
• Grasshoppers
• Shrews

Multiple Choice

The owl and weasel compete for which organism? (if they COMPETE they eat the SAME food)

• Hawk
• Spider
• Grasshopper
• Shrew

Multiple Choice

In this food web, which 2 animals will compete for the same source of energy (if they COMPETE they eat the SAME food)

• grasshopper and rabbit

• deer and insect-eating bird

• shrew and squirrel

• snake and grasshopper

Multiple Choice

The berries and plantain are best known as

• producers

• primary consumers

• secondary consumers

• decomposers

Multiple Choice

What will both the rat and goat compete for? (if they COMPETE they eat the SAME food)

• a rabbit

• the owl

• a tomato plant

• nothing

Multiple Choice

The shrew provides energy for the ...? (who eats the shrew for energy)

• cricket
• grasshopper
• frog
• snake

Multiple Choice

The owl and weasel compete for which organism? (if they COMPETE they eat the SAME food)

• Hawk
• Spider
• Grasshopper
• Shrew