CHAPTER 3: The BIOSPHERE

3-1 What is Ecology?

3-2 Energy Flow

3-3 Cycles of Matter

Ecology

Study of the interactions of organisms with one another and with their physical surroundings.

Earth is a Living PlanetEarth is a single living system.

It is a biosphere.

Figure 1.2.1

A view of Earth from space

Approaching Central Park (the red rectangle in the middle of this photo)

A Central Park woodland

An eastern gray squirrel

A Hierarchy of Interactions

Organismal ecology (individual)

Population ecology (group of individuals)

Community ecology (all organisms in a particular area)

Ecosystem ecology (all organisms and abiotic factors)

Ecosystems

consists of a given area’s physical features

(______________) and living organisms

(______________).

abiotic factors

biotic factors

B. ECOSYSTEM STRUCTURE

 1. abiotic factors – ____________________examples: __________________________

nonliving componentswater, light, heat, gases, minerals

  2. Biotic factors – organisms transfer energy,

participate in cycle of chemicals,

change environment

Homework Due

• Read Pgs. 62-65 (Sect. 3.1)• Section Assessment Quest. #1-5 on pg. 67 (stamp)

Tonight’s homework:-Read pgs. 67-73 (Sect. 3.2)-Do Section Assessment Quest. #1-5

on pg. 73

Introductory Questions #6

1. A group of ecosystems that have the same climate & dominate communities are called _______. (see pg. 64)

2. At what biological levels does the study of Ecology include? (see Fig. 3-2)

3. Ecological research involves three fundamental approaches. Name these three approaches. (see Fig. 3-3, pg. 65)

4. What is the main energy source for all life? (see pg. 67)

5. Explain how an autotroph is different from a heterotroph. Give three examples for each. (see pgs. 67-68)

Ecology analyzes the highest level on the heirarchy (pg. 1082)

Ecosystems

Biotic Factors

Living aspects of an ecosystem such as_____________

_______________, worms, amoebas, and waterlilies.

fishes, frogs, insects, snails,

Biotic Factors

Habitats

• the location or surrounding where the organism lives

Communityorganisms living together in an ecosystem

Niches the behavior of organisms in their habitats.

Abiotic factors

nonliving physical parts of an ecosystem such as _______________ type, rocks, temperature,

_______________, and rainfall.

water, sunlight, soil

humidity, elevation

Wind: Can affect the pattern of a plant’s growth

Abiotic Factors• Temperature• Sunlight• Water & precipitation• Wind• Rocks & Soil• Climate (prevailing weather comb of factors)• Bodies of water: lakes, oceans, rivers• Seasons & positioning of the Earth• Mountains

3-2 Energy Flow

A. The Flow of Energy

1. All energy used by living organisms __________________________

2. Use only ______ of the total energy _________________

originate from the sun.1%

Earth receives from the sun.

Sunlightenergy

Ecosystem

Photosynthesis(in chloroplasts)

Glucose

Oxygen

Carbon dioxide

Cellular respiration(in mitochondria)

Water

for cellular work

Heat energy

All energy used by living organisms:

originate from the sun

SUN PLANTS Herbivores Carnivores 100% 50% used immediately or

by the plants; rest is Omnivores stored within roots as starch

 

PRODUCERS CONSUMERS

4. Energy is _____________________ ______________________

5. The raw materials can be recycled: _______________________

and can’t be recycled!lost with each transfer

atoms/molecules

The dynamics of any ecosystem depends on two processes:

1. Cycling of

nutrients

2. Flow of energy

Figure 1.3

Sunlight

Ecosystem

Heat

Consumers(such as animals)

Heat

Producers(plants and otherphotosyntheticorganisms)

Chemicalenergy (food)

EcosystemLight

Energy flow Producers Consumers Decomposers

Heat

Chemical cycling

(biotic abiotic)

An Overview of Ecosystem Dynamics

SUMMARY OF KEY CONCEPTS

Visual Summary 19.1

a. autotrophic (self-feeding; producers) plants are photosynthetic b. heterotrophic (feeding on others; consumers)

1. Herbivores = ___________________2. Carnivores = ___________________3. Carnivores = ___________________

primary consumerssecondary consumerstertiary consumers

  c. decomposers – or break down organic material into the same abiotic materials that we started with. Yes, nature is the champion recycler!

mainly microscopic fungi andbacteria that metabolize

Detritivores, or decomposers

– Derive their energy from the dead material left by all trophic levels

– Are often left off of most food chain diagrams

Figure 19.22

Introductory Questions #71. What does an ecological pyramid show us? Name the three

types of pyramids discussed on pgs. 72 & 73.2. Which pyramid shows us the amount of potential food

available for each trophic level in an ecosystem?3. Energy is a one-way flow system while matter is _________.

(see pg. 74)4. Name the FOUR geochemical cycles discussed in Sect. 3.3

(pgs. 75-79). Name the cycle that involve:-Evaporation & transpiration _______-Many bacteria & fungi _______-Photosynthesis & respiration _______-Important for organisms making DNA and RNA _______

-Forms nitrates (NO3-), nitrites(NO2

-), ammonia (NH3), and N2 gas. ____.

Energy flows through an ecosystem in one direction, beginning with solar energy.

This stored energy then passes through a food chain, a series of organisms that successively eat one another.

The trophic level, or feeding level, of an organism is the number of food chain links between it and the ecosystem’s energy source.

C. Feeding Relationships

1.    Food chain: follow the progression of energy flow from one organism to another or “who eats whom.”

a. shorter food chains are found in harsh climates like the desert and tundra .

b.  Desert or tundra areas are less stable and more easily destroyed than those found in more moderate climatic influences e.g.

tropical rain forests.

2.    Food webs: food chains interconnect, forming complex food webs.

a. webs form when one species eats or is eaten by several other species and when one species functions at more than one trophic level.

b.   Example: a person eating a tuna sandwich is both a primary consumer (a herbivore, eating bread) and a tertiary consumer (a carnivore eating another carnivore, the tuna).

Trophic Levels and Food Chains

Visual Summary 19.2

Autotrophs Heterotrophs

Light

Producer

Energy and chemicals

Herbivore (primary

consumer)

Carnivore (secondary consumer)

Detritus

Detritivore(decomposer)

Organic and

inorganic compounds

LEVEL NAME KIND OF ORGANISM

TYPES OF FEEDING

ENERGY SOURCE

1st trophic Primary producer

Plants Autotroph Sun

2nd trophic Primary consumer

Herbivores Heterotroph Plants

3rd trophic Secondary consumer

Carnivore Heterotroph Herbivores

4th trophic Tertiary consumer

Top carnivore

Heterotroph Carnivores

5th trophic decomposer Detritivore Heterotroph All other organisms

A food chain:

Trophic Levels and Food Chains

– Is the sequence of food transfer from trophic level to trophic level

– May have many levels

Figure 19.21

Carnivore

Carnivore

Carnivore

Herbivore

Plant

A terrestrial food chain

Quaternary consumers

Tertiary consumers

Secondary consumers

Primary consumers

Producers

Carnivore

Carnivore

Carnivore

Zooplankton

Phytoplankton

A marine food chain

Feeding Relationships

D. Ecological Pyramids

1.   shows energy relationships among each trophic level

2.   way of visually demonstrating a food chain

3.   shape of the pyramid shows that the transfer of energy from one level to the next is not that efficient

4.   Note that 90% of all the grasses and cereal grains fed cattle are used and lost by a cow as body heat, wastes and to

provide the energy for a cow to survive. Only 10% is actually used in

manufacturing muscle tissue (beef steaks).

6. Relative to the human diet, it is more efficient to eat plant materials than to eat the cows that ate the plant material.

Some 90% of all the grain produced in this country is fed to livestock.

  5. The base level of a biotic pyramid contains plant life; the greatest number of individuals; the greatest amount of potential food energy; and, the greatest amount of biomass (weight).

Approximately 90% loss of energy at each trophic level

Energy

Biomagnification (DDT,PCB,Metals)

Food Chain Efficiency

Cod, Tuna, Marine

Mammals

Phytoplankton, Diatoms, Cyanobacteria

Zooplankton, Copepods, Krill

Squid, Sardines, Anchovies, Herring

.00003 PPM

..003 PPM

.04 PPM

.5 PPM

5 PPM 0.20 BT

2 BT

20 BT

200 BT

10%

10%

10%

Biological Magnification Trophic process in which retained substances become more concentrated at higher levels

See pg. 1202 another example PCB

(polychlorinated biphenyls) in the Great lakes.

What Happens as Energy Moves Through a Food Chain?

• Energy is lost mainly as heat in each transformation

What Happens as Energy Moves Through a Food Chain?

• Organisms are not 100% efficient

– Only 10% of the energy at one level makes it to the next level (90% lost)

• Always have a pyramid shape• energy is always lost as you go up

• Shape = the 10% rule• More energy is maintained if there are

fewer levels • why we should eat lower off the food

chain

Pyramid of Energy

Eating producers instead of consumers requires less photosynthetic productivity (feeding the cows) and reduces the impact on the environment

Figure 19.27

Secondary consumers

Primary consumers

Producers

Human vegetarians

Corn

(a)

Humanmeat-eaters

Cattle

Corn

(b)

•Transfer of harmful chemicals Transfer of harmful chemicals throughout the ecosystemthroughout the ecosystem

•DDT and other pesticides DDT and other pesticides

•PCB’s & other endocrine PCB’s & other endocrine disrupterdisrupter

BioamplificationBioamplification

3-3 Cycles of MatterA. Biogeochemical Cycles:

1. Water cycle

a. driven by (2) processes: evaporation and condensation

b. water enters the atmosphere by transpiration of plants as well as evaporation.

c. condensation = forms H20 into rain clouds

d. precipitation = release of H20 from clouds to

surface

2. Nitrogen cycle

a. sources = atmosphere (gas) = 78% of atmosphere

b. found in waste products, dead and decaying organisms

c. Nitrogen fixation: takes nitrogen from atmosphere and converts nitrogen into a useful form. Process:

N2 nitrates (NO3-) and nitrites (NO2-)

Nitrifying bacteria causes this to occur which can be found on roots of plants called legumes (examples of legumes: peanuts, beans, peas)

d. Denitrification: denitrifying bacteria in soil break down these nitrogen compounds from dead plants and animals that have been decomposed. Through this process, free nitrogen is returned to the atmosphere

Nitrogen CycleNitrogen Cycle

Bacteria and how it helps to from Bacteria and how it helps to from Nitrates in soilNitrates in soil

The Water Cycle

Figure 19.29d

Precipitation over the sea

(283)

Solar heat

Water vapor over the sea

Oceans

Net movement of water vapor by wind (36)

Evaporation from the sea (319)

Evaporation and transpiration (59)

Water vapor over the

land

Precipitation over the land (95)

Surfacewater and

groundwater

Flow of water from land to sea

(36)

(d) The water cycle

Figure 19.29b

Denitrifying bacteria Assimilation

by plants

Nitrogen (N2) in atmosphere

Amino acids and proteins in plants and

animals

Detritus

Detritivores

Nitrogen-fixing bacteria

in root nodules of legumesDecomposition

Nitrogen fixation Nitrogen-

fixing bacteriain soil

Ammonium (NH4

+ )Nitrifying bacteria

Nitrates (NO3

– )

The Nitrogen Cycle

(b) The nitrogen cycle

3. Carbon and oxygen cycles

a. CO2 makes up only .035% of gases in

atmosphere, but plays a crucial role in supporting biotic component.

b. photosynthesis takes in CO2, animals gain

carbon by consuming photosynthesizers; carbon stored in living systems collectively makes up biomass;

respiration and action of decomposers releases CO2 back into abiotic part of

ecosystem.

c. Flow of carbon (and food) in ecosystem:

Atmospheric CO2 plants animals decomposers Atmospheric CO2

d. Oxygen cycle:

Photosynthesis: H20 is split,

Respiration: H20 is released

releasing oxygen. and then absorbed by plants

Figure 19.29a

CO2 in atmosphere

Burning

Wood and fossil fuels

Cellular respiration

Higher-level consumers

Decomposition

Detritivores

Photosynthesis

Producers

Primary consumers

Detritus

(a) The carbon cycle

The Carbon Cycle

Figure 7.3

Meso-phyll

Vein

Stomata

Leaf cross section Mesophyll cell

Chloroplast

Innermembrane

Outermembrane

Grana Stroma Thylakoid Thylakoidspace

Oxygen Cycle

Photosynthesis: H20 is splitreleasing oxygen

Respiration: H20 is released and then absorbed by plants

B. Nutrient Limitation

1.    Law of the minimum/limiting factor – where one abiotic factor is deficient enough to be ecologically limiting, thereby exerting a powerful influence on the entire ecosystem

2.    What is the limiting factor in the desert?

3.    What is the limiting factor in the tropics?

H20

Minerals in the soil and sunlight

SUMMARY OF KEY CONCEPTS

Chemical Cycling Between Photosynthesis and Cellular Respiration

Visual Summary 6.1

Sunlight

Heat

PhotosynthesisCellular

respiration

Geochemical Cycling (4 cycles)• Biogeochemical cycles: the various nutrient circuits, which involve both abiotic and

biotic components of an ecosystem• Water• Carbon• Nitrogen• Phosphorus

THE END!

Tonight’s Homework• Review/Grade your Review Quest. Using Key from

my website. (use RED PEN and add information)• Do the following review Questions for Ch. 3 & 4:

– Pg. 83 #1-10, and #14, #17, #20, #23, and #24– Pg. 85 #1-7– Pg. 115 #1-10, and #14, #18, #23– Pg. 117 #1-9

• Look at the Key for these questions using the hyperlinked PPT. file on my website and grade you answers using a RED PEN

**Take the SELF Tests for chapters 3 & 4 using the online textbook and print out the results & attach to your packet.

Assignment Packet Ch. 3 & 4• Cover page (Name, Period, Date, & Chapters)• Text book Work (Section Assessment Q’s)

– Pg. 89 #1-5 -Pg. 65 # 1-5– Pg. 97 #1-6 -Pg. 73 # 1-5– Pg. 105 #1-6– Pg. 112 #1-5

• Videos x3– FOUR segments of “Human Factor”– Curtain Calls: Predator/Prey interactions– Biomes (min. ten statements)

• IQ’s x7• End of Chapter/Review Work (Graded w/Red PEN)

– Pgs. 83, 85, 115, & 117 (Tonight’s Homework)• Self Test for Chapter 3 & 4

Figure 19.23

Quaternary,

tertiary,

and secondary consumers

Tertiary and

secondary consumers

Secondary and

primary consumers

Primary consumers

Producers (plants)

Energy Pyramids

Visual Summary 19.3

Approximately 90% loss of energy at each trophic level

Energy