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Ecology

Ecology is the study of the __________________________________ with one another and their ______________________________________________.

LEVELS OF ORGANIZATION IN ECOLOGY

Fill in the boxes below with the words to the right. Then write down the definition next to the word.

Organism

Population

Community

Ecosystem

Biome

Habitat

COMMUNITY INTERACTIONS

Using a line match the following pictures with the terms below and complete the boxes

under each picture:

Commensalism

Mutualism

Predation

Bee pollinating a

flower +/+

Barnacle on a whale

___/____

Bat eating a frog

___/___

Mistletoe on a tree

___/___

Revised June 2014

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Parasitism

BIOTIC VS ABIOTIC

Biotic--All the LIVING or ONCE LIVING components of an ecosystem. Also includes the products of living things.

Abiotic factors-All the NON-LIVING components of an ecosystem

Using the list below write an “A” next to factors you think are abiotic and a “B” next to the factors you think are biotic.

____water

____temperature

____soil

____owl

____bacteria

____precipitation

____dead leaf

____ light

____humidity

____tree

____feces

____fingernail

FOOD WEBS, FOOD CHAINS, AND THE FLOW OF ENERGY

Food Chain: Describes one ______________relationship and one _______of ______________ through food consumption. Draw in arrows that show energy flowing toward the organism doing the eating.

Food Web

shows the _____________________ between a wide ________________of organisms in the________________

creating a complicated, ________________________path of _________________________________.

They are used to study ____________________ of the ___________________ or __________________of a ____________________ in an environment

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Write the definitions to the terms in the space next to the word. Then fill in the legend below so that it matches with

the colors in the boxes. Also give an example from the food web for each term.

Producer--

Also Known As (AKA):

Example(s):

Consumer—

Primary --

AKA:

Example:

Secondary--

AKA:

Example:

Tertiary--

AKA:

Example:

Quaternary—

AKA:

Example:

Carnivore--

Example

Herbivore--

Example:

Omnivore--

Example:

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Using the aquatic food web above, explain what would happen if the zooplankton population drastically declined.

Explain what would happen if the reef shark population drastically increased.

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Biodiversity of World Biomes

The Biosphere In 2002 , about ___________________ species had been discovered and identified by biologists.

The sum of Earth’s ecosystems, the ___________ encompasses all parts of the planet inhabited by

__________________.

Terrestrial Biomes The term biome refers to

______________________________________________

that typifies a broad geographical region. It is a major

regional ____________________.

Characterized by the ____________________ and

______________________ that thrive there.

6 major terrestrial biomes

1. Tundra (________________ and ________________) Climate: Plant Communities:

2. Temperate forest (_____________________) Climate: Plant Communities:

3. _____________ Climate: Plant Communities:

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4. _____________ (coniferous, needle leaf or boreal forests) Climate: Plant Communities:

5. Grassland Climate: Plant Communities:

6. ____________ rain forest Climate: Plant Communities:

Marine Biomes: There are________ marine Ecosystems

Marine Ecosystem Locations (m)

Estuaries and Freshwater Biomes (check the appropriate boxes)

Biomes Mix of Salt and Fresh

Water Fresh Water Moving Standing

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Biodiversity

• For at least ______________________, a complex web of life has been evolving here on Earth.

• Biodiversity ( short for biological diversity) - is the _________________ of all living organisms and their

____________________________________. Scientists often speak of three levels of diversity –

– __________________

– __________________

– and __________________ diversity.

An ecosystem’s health is typically measured in ___________________________________________.

The loss of even a single species can harm the ________________________ of an ecosystem

Biodiversity Hotspots

Example: Tropical Rain Forests

• Warm and moist environment

• Cover ________________ of the Earth’s ground surface

• ______________ of all the planet’s species.

• Important to conserve!-Why?...

Hotspot Defined:

• Areas ________________________ but threatened by human activity.

What would happen if… 1. the grass population was wiped out?

2. the grass population recovered but many of the marmots died because a disease?

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Importance of Biodiversity:

The rich variety of species in biological communities gives us:

___________________________,

___________________________,

___________________________,

___________________________,

___________________________,

___________________________, and

___________________________,

All of which pour hundreds of millions of _________________, into the world _______________, each year.

People have a __________, affinity for nature, a sense of “______________________,” wherein they assign a

non-utilitarian value to a tree, a forest, and wild species of all kinds

E. O. Wilson

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Energy Flow Pyramids

TROPHIC LEVELS

An organism’s trophic (feeding) level is determined by its_______________________________________.

There are 3 main trophic levels in a food web. They are:

1. AUTOTROPHS: • Capture energy from the_______________ (photosynthetic) or _____________________molecules

(chemosynthetic) and converts it into ______________________________________. • Also known as (AKA) _____________________________

– produces food (make energy storing molecules), • Eg.

• 2. HETEROTROPHS- • AKA ________________________________

– obtains the energy to build their molecules by ____________________________ plants or other organisms

Includes: – primary, – secondary, – tertiary (etc.) consumers, and

– decomposers and detritivores

• 3. SAPROTROPHS- AKA _______________________________________________

An organism that feeds off of __________________________________ organic matter Examples:

-_________________

-____________________ DETRITIVORES

Organisms that eat detritus, or ________________________________________

– Eg. ________________________________________________

DECOMPOSERS

A kind of _____________________________________

– Break down organic matter into _________________________________________. • release ___________________________________ back into the

environment to be recycled.

– Eg. _______________________

Revised June 2014

51

ENERGY

Organisms convert food (___________) into ______________. This energy is given off as ____________ which is lost to space. Energy is a ______________________. It is not a cycle.

Energy Flow Pyramids An energy flow pyramid is a diagram that compares ____________________ used by producers, primary consumers, and other trophic levels.

• As a rule each trophic level receives only __________ from the trophic level below.

• In other words each trophic level loses ____________ heat to

the atmosphere. Study the food web below and convert it into an energy pyramid model. The autotrophs in this food web start off with

123,000 kilojoules of energy and the decomposers are included on the outside of the pyramid. Also label the levels with

the following terms:

Autotroph

Producer

Primary consumer

Secondary consumer

Tertiary consumer

Herbivore

Carnivore

Heterotroph

Decomposer/Detritivore

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BIOMASS PYRAMID

Biomass is the mass of organisms minus water. Biomass refers to the amount of carbon and other trace elements in an

organism’s body contains.

Study the food web below and convert it into a biomass pyramid model. The autotrophs in this food web start off with

5,693,112 Kg of biomass and the decomposers are included on the outside of the pyramid. Also label the levels with the

following terms:

Autotroph

Producer

Primary Consumer

Secondary Consumer

Tertiary Consumer

Herbivore

Carnivore

Heterotroph

Decomposer/Detritivore

NUMBERS PYRAMID

A graphic showing the______________________________ at each trophic level. In this graph you can see that it shows

approximately 90% loss of individuals at each trophic level.

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HUMAN POPULATION GROWTH

How can more people be

supported on Earth when

there is a limited supply of

resources? It depends on

________________________

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Clumped

Examples:

Nearly Uniform

Examples:

Random

Examples:

Populations Definition of population--All the members of a ________________ that live in ________________ at _______________.

Geographic dispersion—the way in which ____________________ of a population are spread in an ________________

or ________________________.

Using dots, illustrate the different dispersion types and list examples of organisms for each dispersion.

Population Size--The number of ____________________ in a population.

Depends on: Birth (____) Death (____) Emigration: movement of individuals _________________ a population ( ____) Immigration: movement of individuals ___________a population (____)

What if there were 1267 rabbits in a colony. In one year 1500 rabbits were born, 1285 died, 65 emigrated and 0 immigrated. What is the new size of the population? ____________________

By how much did the population grow? ______________________ What would the number look like if there was a decline in population growth?

_________________________

Population Growth Rate—The amount by which a population’s ______________ changes ________________________.

There are 2 types of population growth rates

1.

2.

Revised June 2014

55

1. Exponential Model of Population Growth

A population ___________________ exponentially when resources are ______________________________.

If a population grows exponentially, the population size __________________________________ over a period of time.

Do the math:

Fill in the chart below to get a sense of exponential growth.

Time (minutes) Formula Number of Cells

0 20 1

20 21

40 22

60 23

80 24

100 25

120 26

140 27

160 28

180 29

200 210

Exponential growth is an example of ___________________ ______________.

o The more ______________ there are, the more _____________will be born who, in turn, grow up to have ________________________________ and so on.

Positive feedbacks can be expressed in graph form as well—the graph is shaped like the letter ________.

Using the graph to the right:

1.trace in a trend line to show exponential

growth and positive feedback.

2.label the x and y axis with appropriate terms

and

3.add a title to the graph.

Exponential Growth Curve

Positive Feedback Loop

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Negative Feedback Loop

2. Logistic Model of Population Growth

Exponential growth is not sustainable long term!!!

Most populations face ______________________________ and thus show a __________________ growth rate.

Populations are limited by _________________________________________________________________________.

Using the graph to the right

1.add in a trend line to show logistic

growth and negative feedback.

2.label the x and y axis with appropriate

terms and

3.add a title to the graph.

In addition label the following phrases

on the graph:

Birth rate increases Death rate increases Carrying capacity

According to the graph how many individuals will this environment carry for the long term? ___________

Logistic growth is an example of

_____________________________.

Since resources are limited, there is competition for

these resources, therefore ____________________

rise, causing the population to

__________________.

Negative feedbacks can be expressed in graph form as well—the graph is shaped like the letter ________ (logistic).

Definition of Carrying Capacity:

Stretched out __________

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Often the population _______________________ up and down, but there is an overall _______________________ to

the population.

On the logistic curve to the right draw in the where the

carrying capacity is located on the graph.

Remember:

Carrying Capacity is

The number of individuals

the environment can support

over a long period of time

Limiting factors cause negative feedback loops. There are 2 types of limiting factors:

abiotic

biotic

Examples of abiotic limiting factors

_________________________

_________________________

Examples of biotic limiting factors

________________________

________________________

Population density

Definition: Number of _________________per ______________________.

Do the math:

In a 3 km2 area there are 7 deer. What is the density of the deer population?___________________

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Population Regulation

1. Density Independent Factors: factors that ______________ population regardless of population ________.

Examples: _______________

_______________

_______________

2. Density Dependent Factors: factors triggered by _________________ population ___________________.

Examples:

________________

________________

_________________