Chapter 2
Section 2-1
Organisms and Their Environment
Ecology
The branch of Biology that studies the
interactions between organisms and their
environment, (living and nonliving)
Ecology
How do you use Ecology in your life?
Food- planting, hunting, fishing
Pets- fleas/ticks, cleaning, food, range
Survival- soccer team in Andes “life”
Garbage- compose, leaves, recycling
Energy- solar, hybrid, water
Ecological Questions???
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Why do birds migrate?
Why does a lizard camouflage itself?
Why might a forest fire be beneficial?
What are some affects of acid rain?
Ecology
Ecology as a science was developed in the
1960’s as man began to realize the
profound effect of his actions on the living
world.
Tropical Rainforest Example
Why is it important to us?
– ½ world’s species (loss of species)
– Deforestation for logging
• Lower O2 production, Increase CO2 production
• Global Warming caused by Greenhouse Effect
– Why don’t they just stop?
• Poor countries / Poor individuals
Ecology
Biotic vs. Abiotic Factors
Biotic – living factors in the environment
Abiotic – nonliving factors in the environment
7 abiotic factors- can you name them?
Seven abiotic factors
1.
2.
3.
4.
5.
6.
7.
Soil
Temperature
Moisture/ Water
Light
Wind
Air Composition (O2)
Natural Disasters
Abiotic vs. Biotic Factors
Ground Mole
Biotic
Abiotic
Other moles
Roots
Grubs
Predators
Humans
Soil type
Moisture
Temperature
Try these:
Bird, Deer, Street Person
Ecology
• Bird, Deer, Street Person
Ecology
Ecosystems
Area where organisms interact with one
another and the living and nonliving
environment
Ecology
Population vs. Community
Population – a group of organisms of the
same species living in an ecosystem
Community – all the populations in a given
area
Ecology
Levels of Organization
Page 40
Biosphere (all ecosystems)
Ecosystem (living and non-living)
Community (all species)
Population (one species)
Organism (individual)
Ecology
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Track a deer for one year
Role of a deer and interaction with its herd
The affects of vegetation on deer movement
Affects of a harsh winter on deer
Global population of deer
Ecology
Habitat vs. Niche
Habitat – the place where an organism lives
Niche – the role of an organism in a
community
“total way of life”
Ecology
• Habitat- where it lives
– Birds- forest tree nest
– Dead Log Habitat
• Niche- role in the community
– Food, space, conditions
• Temperature, time of feeding, type of food
• Two organisms cannot share a niche
Quiz
1. Give one biotic factor, abiotic factor, the habitat
and niche of a Lion.
2. Give the habitat and niche of a shark.
3. List the 5 levels of organization, beginning with
organism.
4. How many of the 7 abiotic factors can you list?
5. What are the 2 main reasons for saving the
rainforests?
Symbiosis- “Living Together”
A close and permanent association between
organisms of different species
1. Mutualism
2. Commensalism
3. Parasitism
Types of Symbiosis
Mutualism – both species benefit
Examples
• Legume plants and nitrogen-fixing bacteria
• Ants and acacia trees (pg.44)
• Bacteria and cow
• Bird and crocodile
• Bees and flowers
Types of Symbiosis
Commensalism – one species benefits and
the other is neither harmed or benefited
Examples
- Remora and shark
- Bird and cattle
- Orchids, mosses and ferns on a tree
Types of Symbiosis
Parasitism – one organism benefits and the
other is harmed, but usually not killed
Examples
12345
- Australian Rabbits
- Virus, bacteria, flukes, tapeworms
- Ticks, mosquitoes, leech, lamprey
* Vaccinations (prevention)
smallpox and polio
Chapter 2
Section 2-2
Pages 46-57
Autotrophs vs. Heterotrophs
Autotrophs – organisms that make their food
(self-feeder)
Photosynthesis and Chemosynthesis
(50% efficient)
Autotrophs vs. Heterotrophs
Heterotrophs – organisms that depend on
others for nutrients
(other-feeder)
They cannot make their own food,
they must consume it.
(10% efficient)
Autotrophs vs. Heterotrophs
• Why do you think autotrophs are more
efficient than heterotrophs?
Ecology
Roles of Organisms in an Ecosystem
Producers – autotroph’s that change the
sun’s energy into chemical energy in
organic molecules during photosynthesis
Examples – green plants and algae
Ecology
Consumers- heterotrophs
Herbivore – “plant-eaters” feed only on producers
Carnivore – “meat-eaters” feed only on consumers
Omnivores – eat both plants and animals
- feed on producers and consumers
- advantage or disadvantage?
Ecology
Roles of Organisms in an Ecosystem
Scavengers – animals that feed on other
dead animals
Examples – vulture, buzzard, maggots
Ecology
Roles of Organisms in an Ecosystem
Decomposers – organisms that break down
dead organic material
Examples – fungi and bacteria
Trophic Level- Feeding step
Producers
First Order Consumers – herbivores
(mouse)
Second Order Consumers – carnivores
(raccoon)
Third Order Consumers – larger carnivores
(large cats, wolf)
Food Chains
Model showing how matter and energy move
through an ecosystem.
Shows only one organism feeding on another.
Food Chain
Sun Producers 1st order consumer
 2nd order consumer
 3rd order consumer
 Decomposers
Each arrow (→) represents energy flow
Each step represents a trophic level
Food Chain
Food Web
- Model showing all possible feeding
relationships at each trophic level in a
community.
- Network of interconnected food chains
- Many options for food
Food Web
Water Cycle
Evaporation/Transpiration
→ Condensation
→ Precipitation (4 Types)
→ Runoff/Groundwater
Water Cycle
Carbon Cycle
Carbon is found in the environment as
carbon dioxide gas (CO2)
How does carbon get into the environment?
- Burning fossil fuels, forests and organic
material
- Respiration
Carbon Cycle
- CO2 is used by producers for photosynthesis
carbon dioxide + water = simple sugars.
- Sugars passed to consumers eating them.
Nitrogen Cycle
Nitrogen-fixing bacteria convert atmospheric
nitrogen into useful compounds
(legume plants- bean)
Legumes convert nitrogen into nitrates.
Nitrogen Cycle
- Herbivores convert plant proteins into
animal proteins.
- Animal proteins are then passed to
consumers
- Organisms return nitrogen to the
environment when they die or defecate
Phosphorus Cycle
Phosphorus is a mineral that come from the
breakdown of rocks.
Plants use phosphorous from the soil in their body
tissues and it passes to each consumer.
How long is this cycle?
Stranded on an island!
A small group of people are stranded
on a barren island. They have 500
bushels of wheat and one cow. What
should they do to survive for the
greatest length of time?
Stranded on an island!
a. Eat the cow and then the wheat
b. Drink the cow’s milk, eat the cow, then eat the wheat
c. Don’t feed the cow but drink the cow’s milk, eat the
cow when milk production ceases, then eat the
wheat
d. Feed the wheat to the cow and drink the milk
e. Feed the wheat to the cow, drink the milk, then eat
the cow
f. Eat the wheat and then eat the cow