Food Webs and Energy Pyramids

FOOD
WEBS

Energy Pyramids and

Biodiversity

FOOD
WEBS

Lesson Agenda

AMOEBA SISTERS
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Take notes on KEY concepts and points of confusion during the presentation

TAKING NOTES

Complete the questions, use your notes, and apply your knowledge.

CHECK FOR UNDERSTANDING

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Watch

and Listen

LESSON

CONTENTS

FOOD CHAINS

ENERGY PYRAMIDS

FOOD WEBS

BIODIVERSITY

DECOMPOSERS

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FOOD

CHAINS

a food chain is a series of

organisms that eat one another

so that energy and nutrients

flow from one to the next

WHO ARE THE PLAYERS?

These are autotrophs,
like plants, that make their own food

PRODUCERS

These are heterotrophs, like animals, that eat producers and other consumers

CONSUMERS

These are heterotrophs, like
mushrooms, that break down dead plants and animals

DECOMPOSERS

PRODUCERS

make their own food

CONSUMERS

eat producers and

other consumers

DECOMPOSERS

break down dead

plants and animals

Sun

(source of energy)

CK-12. "Food Chains and Food Webs." Retrieved October 28, 2022 from https://www.ck12.org/biology/food-chain/lesson/Food-Chains-and-Food-Webs/

LEGEND:

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Which way do the

arrows point in a
food chain? Why?

Multiple Choice

1. What do all food chains start with?

• Apex Predators

• Primary Producers

• Primary Consumers

• Secondary Consumers

Multiple Choice

What is an autotroph?

• An organisms that must eat food for energy

• An organism that has the ability to make it's own food through photosynthesis

Multiple Choice

What are heterotrophs?

• Organisms like animals and mushrooms that get their nutrients from eating plants or other consumers

• Organisms that do not need to eat because they can make thier own food

Multiple Choice

What are primary consumers eaten by?

• Tertiary consumers
• Decomposers
• Producers
• Secondary consumers

Multiple Choice

What are secondary consumers eaten by?

• Decomposers
• Quaternary consumers
• Tertiary consumers
• Primary consumers

Multiple Choice

Which way do the arrows point in a food chain?

• Arrows point in random directions in a food chain.
• Arrows point from the organism doing the eating to the organism being eaten.
• Arrows point from the sun to the plants in a food chain.
• Arrows point from the organism being eaten to the organism doing the eating.

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ENERGY

PYRAMIDS

An energy pyramid is a

model that shows the flow
of energy from one trophic,
or feeding, level to the next in an ecosystem

TAKE NOTES

If the Primary Producer has
1,000 units of energy, how
much will be available for

secondary consumers?

Practice 1

10 % RULE

If the Secondary

Consumers have 500 units
of energy, how much did
Primary Consumers have?

Practice 2

If Primary Producers have
654.3 units of energy, how

much will the tertiary

consumers have?

Practice 3

What percentage of energy

is USED/LOST at each

trophic level?

Practice 4

Multiple Choice

What is trophic level 1 of the energy pyramid?

• Consumers
• Producers
• Decomposers
• Secondary Consumers

Multiple Choice

What is trophic level 2 of the energy pyramid?

• Primary consumers
• Decomposers
• Secondary consumers
• Producers

Multiple Choice

How much energy is lost/used at each trophic level?

• Approximately 50% of energy is lost/used at each trophic level.
• Around 75% of energy is lost/used at each trophic level.
• Less than 10% of energy is lost/used at each trophic level.
• Roughly 90% of energy is lost/used at each trophic level.

Multiple Choice

Where does the energy that was not used but rather is lost go?

• Straight to the ground again

• Into the atmosphere as heat energy

• It is stored in the organisms cells for later

FOOD WEBS

Food web, a complex network

of interconnecting and
overlapping food chains

showing feeding relationships

within a community

insects

chipmunk

rabbit

bear

hawk

elk

fungi

flowers

grass

seeds

grouse

PRODUCERS

make their own food

CONSUMERS

eat producers and

other consumers

DECOMPOSERS

break down dead

plants and animals

Sun

(source of energy)

CK-12. "Food Chains and Food Webs." Retrieved October 28, 2022 from https://www.ck12.org/biology/food-chain/lesson/Food-Chains-and-Food-Webs/

EXAMPLE OF A FOOD WEB IN THE FOREST

LEGEND:

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BUILD A FOOD WEB in Your Notebook

BIODIVERSITY

Biodiversity is all the different
kinds of life you'll find in one
area—the variety of animals,

plants, fungi, and even

microorganisms like bacteria

In your notebook, explain trophic cascades in your own words using examples

from the video.

Why is Biodiversity
Important?

How does a change in
biodiversity affect
the health of an
ecosystem?

DECOMPOSERS

Decomposers break down
the remains and other wastes and release simple inorganic
and release simple inorganic molecules back to the environment

Multiple Choice

What happens if something is removed from a food chain?

• Disruption of the ecosystem balance
• Increase in biodiversity

• Increase in food production
• Enhancement of the ecosystem balance

Multiple Choice

What is a food web?

• A food web is a diagram that shows the interconnected food chains within an ecosystem.
• A food web is a network of restaurants that only serve spider-related dishes.
• A food web is a cooking website that specializes in recipes for spiders.
• A food web is a type of spider web made of food items.

Multiple Choice

What is biodiversity?

• Biodiversity is the process of photosynthesis in plants.
• Biodiversity is the variety of weather patterns on Earth.
• Biodiversity is the variety of life forms on Earth.
• Biodiversity is the study of rocks and minerals.

Multiple Choice

how biodiversity contributes to sustainability?

• Biodiversity leads to increased pollution
• Biodiversity provides essential ecosystem services and enhances resilience to environmental changes.
• Biodiversity decreases the quality of life for humans
• Biodiversity has no impact on sustainability

Multiple Choice

Why are decomposers important?

• Decomposers break down dead organisms and organic matter, recycling nutrients back into the ecosystem.
• Decomposers reduce the amount of oxygen in the environment.
• Decomposers have no impact on the nutrient cycle.
• Decomposers create new organisms in the ecosystem.