Bell Ringer

1) In the simple ecosystem shown below,

determine the species richness.

2) “The specific environment in which an

organism lives, including biotic and abiotic

factors” is the definition of which term below?

a) Niche

b) Ecosystem

c) Habitat

d) Biomed) Biome

e) Community

3) An organism’s role in the flow of energy, its

resource consumption and its species-species

interactions all make up its __________

a) Habitat

b) Niche

c) Ecosystem

d) Biomed) Biome

e) Predator-prey relationships

4) The graph below best describes which biome?

a) Tropical Dry Forest

b) Tundra

c) Temperate grassland

d) Savanna

e) Tropical Rain Forest

Energy Flow and Food WebsEnergy Flow and Food WebsEnergy Flow and Food WebsEnergy Flow and Food WebsPgs 148-150

Energy Movement

• Of all the species-species interactions within

an ecosystem, the most important is the

movement of energy.

• As an organism feeds on another, matter and

energy are moved through the ecosystem.

Energy – Review

• The ultimate source of energy for earth is the Sun.

• Through photosynthesis, autotrophs convert solar

energy into chemical energy in the form of

glucose.

• Autotrophs and heterotrophs then use the process • Autotrophs and heterotrophs then use the process

of cellular respiration to convert chemical energy

in glucose into ATP.

Energy Movement

• Trophic Level – rank in the feeding (energy)

hierarchy.

• There are three primary trophic levels in every

ecosystem:ecosystem:

– Producers

– Consumers

– Detritivores and decomposers

Trophic Levels

• Producer – an organism that uses energy

from sunlight to produce food.

Trophic Levels

• Producer – an organism that uses energy from sunlight to produce food.

• Form first trophiclevel of any food chainfood chain

• Examples:

Plants, Algae

Trophic Levels

• Primary Consumer – an organism which gets

its energy from producers.

Example: Ants, Caterpillars,

Deer

Trophic Levels

• Secondary Consumer – an organism which

gets its energy from primary consumers.

Example: Birds, Spiders, Lion

Trophic Levels

• Tertiary Consumer – an organism which gets

its energy from secondary consumers.

Example: Owls feed on rodents that feed on grasshoppers

Trophic Levels

• Top – Level Consumer – A consumer at the

top of the food chain.

• (This consumer has no predators).

Example: Humans, Bald Eagles

Trophic Levels

• Detritivores – break down the waste products

or dead bodies of organisms within the

ecosystem.

Example: Millipedes, soil insects

• Decomposers – break down leaf litter and

other nonliving matter into simpler nutrients.

Example: Fungi, Bacteria

Trophic Levels

• Detritivores and Decomposers help recycle

nutrients into the soil and help dispose of

dead organisms.

Food Chains

• Food chain – a linear series of feeding

relationships, showing how energy moves

upward through the trophic levels.

Food Chains

• In a food chain, arrows point toward the

transfer of energy (not to who is eating!)

Food Webs

• A more accurate depiction of how energy

moves through ecosystems is a food web.

• Food web – a visual map of feeding

relationships, highlighting the various paths by

which energy passes among organisms of an

ecosystem. ecosystem.

• Food webs

Creating a Food Web Creating a Food Web

Bell Ringer

1)The eagle is an example of…

a) Producer

b) Primary Consumer

c) Secondary Consumer

d) Tertiary Consumer

e) Top-Level Consumer e) Top-Level Consumer

Bell Ringer

2) In this food chain, an

example of a tertiary

consumer would be…

a) Green plants

b) Insects

c) Fishc) Fish

d) Big Fish

e) Eagle

Bell Ringer

3) What trophic level is

missing from this

food chain?

a) Producers

b) Consumers

c) Detritivores/Decomposers c) Detritivores/Decomposers

d) Autotrophs

e) Heterotrophs

Bell Ringer – AP Practice

4) A decomposer would

recycle nutrients back to a…

a) Producer

b) Detritivore

c) Secondary Consumer

d) Tertiary Consumerd) Tertiary Consumer

e) Primary Consumer

Creating a Food Web Creating a Food Web –– The LAST Day The LAST Day

Energy Pyramid

• 10% Rule –

Only about 10%

of the energy available

at one trophic level is at one trophic level is

transferred to

organisms at the next

trophic level.

Numbers Pyramid

• Numbers pyramids reflect the species evenness values of an ecosystem.

Numbers Pyramid

• Why are there fewer consumers at the top of the pyramid compared to the bottom?

Numbers Pyramid

• With the loss of energy occurring at each level, there is not enough energy to support a large amount of life at the top of the pyramid.

• Keystone species

• Numbers pyramid

• Invasive species