Energy Flow in Ecosystems

Multiple Choice

Where does almost all of the energy that drives life on Earth originate?

• Producers

• Hydrothermal vents

• Sun

• Composers

General Rules:

• Producers (autotrophs) are always first.

• Consumers (heterotrophs) are eaters.

• Primary consumers are herbivores.

• Each step on the food chain is called a trophic level.

• Energy decreases with each trophic level.

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Food Chains

Categorize

Options (11)

Plants

Algae

Autotrophs

Herbivores (plant eaters)

Elephants

Rabbits

Omnivores

Phytoplankton

Eat the primary consumers

3rd consumer

Hawk

Organize these options into the right categories

Producer

Primary Consumers

Secondary Consumers

Tertiary consumers

Drag and Drop

The grasshopper would be referred to as a ​

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Drag these tiles and drop them in the correct blank above

primary consumer.

secondary consumer

producer

Drag and Drop

The bacteria & fungi would be referred to as a ​ ​

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secondary consumers

producers

decomposers.

Multiple Choice

In ecology, there is a term called primary productivity. This is the rate at which an ecosystem's producers make chemical energy. 

Which level on the food chain shown is the only one involved with primary productivity?

• Plants

  (Autotrophs)

• Insects

  Cows

  Horses

• Frogs

  Lizards

• Lions

  Wolves

  Snakes

Multiple Choice

Which is TRUE of this image?

• There are multiple food chains to be seen.

• This is a food web.

• It shows that more than one consumer may eat the same thing.

• All of these are true regarding the image.

Look at this energy pyramid.

Take a mental note of all of the things you notice or already know about energy pyramids.

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Energy Pyramids

Could this energy pyramid be diagrammed as a food chain?

A trophic level is each step on the energy pyramid. Producers are on the first level at the bottom.

Notice the percentages at each trophic level.

Also notice how the size of each level gets smaller.

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Multiple Choice

How much energy is transferred to each trophic level?

• 100%

• 90%

• 50%

• 10%

Multiple Choice

What happens to the other 90% of the energy?

• It is lost

• goes back into the sun

• burned off in the form of heat when our bodies use the energy

• It is destroyed

Open Ended

Notice on this energy pyramid that the vulture has been placed next to the decomposers. Vultures are what we call scavengers.

Why would the vulture be placed on the decomposer trophic level?

Drag and Drop

Cranes are known as​

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feeders, meaning they change their diet with the season. They eat anything from small rodents, fish amphibians and insects to grain, berries and plants.​

Drag these tiles and drop them in the correct blank above

opportunistic

selfish

scavengeristic

Multiple Choice

True or False?

Scavengers can also be described as opportunistic feeders.

• True

• False

Joules (J)is a unit of energy!

Energy pyramids are a way to show the energy that’s transferred.

Large amounts of energy are “lost” between trophic levels!

Energy Pyramids

These show the amount of BIOMASS that is present at each trophic level.

What environment would you find this pyramid in? (aquatic or terrestrial?)

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Biomass Pyramid

This is an aquatic biomass pyramid.

Producers are always on the bottom, remember?

So, phytoplankton are the producers in this pyramid.

Normally though, the producers is the largest level, right??

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Biomass Pyramid

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Here is a biomass pyramid found on land.

Notice the producers actually ARE the largest trophic level.

Let's look back at the aquatic pyramid real quick though!

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Biomass Pyramids

Think about how tiny and small phytoplankton really are!

They weigh very little and take up so little space!

That makes sense then that the phytoplankton trophic level is the smallest on a BIOMASS pyramid!

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This is a parasite pyramid. Think fleas on a dog!

Parasites may produce different shapes of pyramids.

Usually widest at the top—inverted—because a large number of parasite organisms often feed on one host organism.

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Parasite Pyramids

Summary

Today we talked all about ENERGY!

• The sun is what is driving the energy on Earth!

• Food chains and food webs are diagrams that show how and where energy is being transferred.

• We learned about producers, primary, secondary, tertiary consumers, decomposers, scavengers, & opportunistic feeders!

• There is more than one way to place information on a pyramid.

• Each step on a pyramid is referred to as a trophic level.

• We learned about energy pyramids, biomass pyramids, and parasite pyramids.