Transcript chapter 47: biosphere

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 Planet
Earth is a single living system.
It is a biosphere.
A view of
Earth from
space
A Central Park
woodland
Approaching
Central Park (the
red rectangle in
the middle of
this photo)
An eastern
gray squirrel
Figure 1.2.1
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
abiotic factors
(______________)
and living
organisms
biotic factors
(______________).
B. ECOSYSTEM STRUCTURE
nonliving components
1. abiotic factors – ____________________
water, light, heat, gases, minerals
examples: __________________________
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_____________
fishes, frogs,
_______________,
insects,
worms,snails,
amoebas, and
waterlilies.
Biotic Factors
Habitats
• the location
or
surrounding
where the
organism
lives
Community
organisms living together in an ecosystem
Niches
the behavior of organisms in their habitats.
Abiotic factors
nonliving physical
parts of an ecosystem
such as
_______________
water,
sunlight,
type,
rocks, soil
temperature,
_______________,
humidity,
elevation
and rainfall.
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
originate
from the sun.
__________________________
2. Use only 1%
______ of the total energy
Earth receives from the sun.
_________________
All energy
used by
living
organisms:
Sunlight
energy
Ecosystem
originate
from the sun
Photosynthesis
(in chloroplasts)
Glucose
Oxygen
Carbon dioxide
Water
Cellular respiration
(in mitochondria)
for cellular work
Heat energy
SUN  PLANTS 
100%
50% used immediately
Herbivores  Carnivores
or
by the plants; rest is Omnivores
stored within roots as
starch
PRODUCERS
CONSUMERS
4. Energy is _____________________
lost with each transfer
and can’t be recycled!
______________________
5. The raw materials can be recycled:
atoms/molecules
_______________________
The dynamics of
any ecosystem
depends on two
processes:
1. Cycling of
nutrients
2. Flow of
energy
Sunlight
Ecosystem
Heat
Consumers
(such as animals)
Heat
Producers
(plants and other
photosynthetic
organisms)
Chemical
energy (food)
Figure 1.3
SUMMARY OF KEY CONCEPTS
An Overview of Ecosystem Dynamics
Light
Energy
flow
Heat
Ecosystem
Producers
Consumers
Decomposers
Chemical cycling
(biotic
abiotic)
Visual Summary 19.1
a. autotrophic (self-feeding; producers) plants
are photosynthetic
b. heterotrophic (feeding on others;
consumers)
primary consumers
1. Herbivores = ___________________
2. Carnivores = ___________________
secondary consumers
3. Carnivores = ___________________
tertiary consumers
c. decomposers – mainly microscopic fungi and
bacteria that metabolize or break down organic
material into the same abiotic materials that we
started with. Yes, nature is the champion
recycler!
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 #7
1.
2.
3.
4.
What does an ecological pyramid show us? Name the three
types of pyramids discussed on pgs. 72 & 73.
Which pyramid shows us the amount of potential food
available for each trophic level in an ecosystem?
Energy is a one-way flow system while matter is _________.
(see pg. 74)
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
Autotrophs
Heterotrophs
Producer
Light
Energy and
chemicals
Herbivore
(primary
consumer)
Carnivore
(secondary
consumer)
Detritus
Detritivore
(decomposer)
Organic
and
inorganic
compounds
Visual Summary 19.2
LEVEL
NAME
KIND OF
ORGANISM
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
TYPES OF
FEEDING
ENERGY
SOURCE
Trophic Levels and Food Chains
Quaternary
consumers
A food chain:
– Is the sequence
of food transfer
from trophic level
to trophic level
– May have many
levels
Carnivore
Carnivore
Tertiary
consumers
Carnivore
Carnivore
Secondary
consumers
Carnivore
Carnivore
Primary
consumers
Zooplankton
Herbivore
Producers
Plant
Figure 19.21
A terrestrial food chain
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)
5 PPM
.5 PPM
.04 PPM
..003 PPM
.00003 PPM
Cod,
Tuna,
Marine
Mammals
Food Chain
Efficiency
0.20 BT
Squid, Sardines,
Anchovies, Herring
Zooplankton, Copepods,
Krill
10%
2 BT
10%
20 BT
10%
200 BT
Phytoplankton, Diatoms, Cyanobacteria
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)
Pyramid of Energy
• 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
Eating producers instead of consumers requires less
photosynthetic productivity (feeding the cows) and
reduces the impact on the environment
Human
meat-eaters
Secondary
consumers
Primary
consumers
Human
vegetarians
Corn
Producers
(a)
Cattle
Corn
(b)
Figure 19.27
Bioamplification
•Transfer of harmful chemicals
throughout the ecosystem
•DDT and other pesticides
•PCB’s & other endocrine
disrupter
3-3 Cycles of Matter
A. 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 Cycle
Bacteria and how it helps to from
Nitrates in soil
The Water
Cycle
Net movement of
water vapor by
wind (36)
Solar heat
Water vapor
over the sea
Precipitation
over the sea
(283)
Water vapor
over the
land
Evaporation and
transpiration (59)
Precipitation
over the land
(95)
Evaporation
from the sea
(319)
Surface
water and
groundwater
Oceans
(d) The water cycle
Flow of water
from land to sea
(36)
Figure 19.29d
The Nitrogen
Cycle
Nitrogen (N2)
in
atmosphere
Detritus
Amino
acids and
proteins in
plants and
animals
Denitrifying
bacteria
Detritivores
Assimilation
by plants
Decomposition
Nitrates
(NO3– )
Nitrogenfixing bacteria
in root
nodules of
legumes
Nitrogen
fixation
Nitrifying
bacteria
(b) The nitrogen cycle
Ammonium
(NH4+ )
Nitrogenfixing
bacteria
in soil
Figure 19.29b
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, releasing oxygen.
Respiration:
H20 is released and then
absorbed by plants
The Carbon
Cycle
CO2 in
atmosphere
Photosynthesis
Burning
Producers
Wood and
fossil fuels
Cellular respiration
Higher-level
consumers
Primary
consumers
Decomposition
Detritivores
Detritus
(a) The carbon cycle
Figure 19.29a
Oxygen Cycle
Vein
Chloroplast
Mesophyll
Inner
membrane
Outer
membrane
Stomata
Leaf cross section
Mesophyll cell
Grana
Stroma
Thylakoid
Thylakoid
space
Photosynthesis: H20 is split
releasing oxygen
Figure 7.3
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?
H 20
3. What is the limiting factor in the tropics?
Minerals in the soil and sunlight
SUMMARY OF KEY CONCEPTS
Chemical Cycling Between Photosynthesis and
Cellular Respiration
Heat
Sunlight
Photosynthesis
Cellular
respiration
Visual Summary 6.1
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
Quaternary,
tertiary,
and
secondary
consumers
Tertiary
and
secondary
consumers
Secondary
and
primary
consumers
Primary
consumers
Producers
(plants)
Figure 19.23
Energy Pyramids
Approximately 90%
loss of energy at each
trophic level
Energy
Visual Summary 19.3