semester 2, day 2 ecosystem & energy. agenda turn in cornell notes & question responses ...
TRANSCRIPT
Semester 2, Day 2
Ecosystem & Energy
Agenda Turn in Cornell Notes & Question Responses Biodiversity Quiz Ecosystem Lecture 4 Minute Break Reading/Work Time Hand Quizzes back and review
Turn in Cornell Notes and Question Responses
Order
Cornell Notes 34.1
Cornell Notes 34.2
Cornell Notes 34.3
Cornell Notes 34.4
Responses to Section 34.1-34.4 and Chapter 34 Review
Make sure that your name is on your notes/responses
Initial each following page
Keep the papers together, fold the corner if not stapled
Biodiversity Quiz
Complete the quiz silently
When you are finished, place quiz facedown
on desk
When everyone is finished, pass quizzes
forward
Ecosystem Changes
How do certain changes affect an ecosystem?
Climate Changes
Temperature, flooding, global warming, freezing
Can eliminate entire biological communities
New communities will repopulate the area NEW
ECOSYSTEM!
From natural resources (volcanoes)
Ecosystem Changes
How do certain changes affect an ecosystem?
Human Activity
Human-caused global warming, pesticides, deforestation, urban
encroachment, endangered species, acid rain, water
contamination, fossil fuels, dams for hydroelectricity, radioactive
waste, oil spills, air pollution, soil erosion, salting roads, crop
irrigation
All of these can kill populations, resulting in the entire ecosystem
being disrupted
Ecosystem Changes
How do certain changes affect an ecosystem?
Human Activity (cont.)
Spirogyra
PopulationExplodes
EFFECT
Daphnia
Kill withPesticides
CAUSE
Bluegill
Dies from Lack of Food
EFFECT
Smallmouth Bass
Dies from Lackof Food
EFFECT
Ecosystem Changes
How do certain changes affect an ecosystem?
Introduction of Non-Native / Invasive Species
Harmful
No predators
Displace native species
Carry disease
Population Size
Caused by humans
Example: Too many predators, prey die out, then predators
die, and plants the prey ate grow out of control.
Population Size in Ecosystem
PopulationSize
BIRTH
IMMIGRATION EMIGRATION
DEATH
Rates that increasepopulation size
Rates that decreasepopulation size
Organisms enter ecosystem Organisms enter ecosystem
Population Size in Ecosystem Graph of Births and Deaths. Look at the gap
between births and deaths.
Gap gets biggerTherefore, population INCREASESNumber
ofOrganisms
Time
Births
Deaths
Population Size in Ecosystem Graph of Births and Deaths. Look at the gap
between births and deaths.
Gap gets smallerTherefore, population INCREASESNumber
ofOrganisms
Time
Births
Deaths
Population Size in Ecosystem Graph of Births and Deaths. Look at the gap
between births and deaths.
Gap stays the sameTherefore, population INCREASESNumber
ofOrganisms
Time
Births
Deaths
Energy Flow in an Ecosystem Autotrophs: produce their own food. 2 types:
Autotrophs make ENERGY available for all other organisms in the ecosystem.
“self” Phototrophs Chemotrophs
•Organisms with
chlorophyll
•Chlorophyll absorbs
light energy for
photosynthesis
•Converts light energy to
food energy
•When sunlight is
unavailable
•Hydrogen sulfide (H2S)
or carbon dioxide (CO2)
converted to organic
(“life”) molecules.
“Light” “Chemical”
Energy Flow in an Ecosystem Heterotrophs: get energy by consuming other
organisms.
Note: Decomposers: secrete enzymes to break down dead matter & then absorb the nutrients (bacteria and fungi)
Herbivore Carnivore Omnivore Detritivore
•Organisms that consume only plants
•Organisms that consume only other heterotrophs
•Organisms that consume both autotrophs and heterotrophs
•Organisms that consume dead matter (any).•Tend to be bugs.
AKA “Consumers”
Energy Flow in an Ecosystem Decomposers & Detritivores are similar, BUT
DECOMPOSERS
Secrete enzymes to break down
Absorb nutrients
Bacteria, Fungi
DETRITIVORES
Eat & digest
Bugs (generally)
Dead Matte
r
*Note: Scavengers technically eat dead organisms, but will also eat live organisms
Energy Flow: Food Webs Food Chain: simple model; one-way energy
flow Primary Producer Primary Consumer Secondary Consumer Tertiary
Consumer
Arrow shows direction of
ENERGY
*Note:•All primary producers are autotrophs•All primary consumers are herbivores (a type of heterotroph)•Higher consumers can be omnivores OR carnivores
Energy Flow: Food Web Food Web: Interconnected food chains;
complex
Energy Flow: Ecological Pyramids Ecological pyramids: show relative amounts of
energy, biomass, or # of organisms.
Tertiary Consum
erSecondary Consumer
Primary Consumer
Primary Producer
Trophic Levels
Template
Energy Flow: Ecological Pyramids Pyramid of Energy
0.1%
1% Energy
10% Energy
100% Energy
Ener
gy L
ost a
s Hea
t (90
%)
AvailableEnergyDecreases
Energy Flow: Ecological Pyramids Pyramid of Biomass (total mass of life @ each
level)
1.5 g/m2
11 g/m2
37 g/m2
809 g/m2
AvailableBiomassDecreases
Note: Mass/Area
Energy Flow: Ecological Pyramids Pyramid of Numbers (# of Organisms)
10,000
90,000
200,000
1,500,000
PopulationSizeDecreases
4 Minute Break
Stay on this floor, otherwise privilege will be
revoked
Be back in the class by ______.
Reading / Work Time
Read Chapter 2
Do the Chapter 2 Assessment Questions #1-
15, 17-24
Come show me your responses when you are
finished.
If you don’t finish, it is homework!
Reminder dp.davincischools.org/staff/blarkin