Transcript Levels of Organization

Levels Within Levels
• An ecosystem is a collection of all the organisms that live in a
particular place, together with their nonliving, or physical,
environment. Within an ecosystem, there are several levels of
organization. Your school and its grounds are similar to an
ecosystem.
•1. What living things are found in and around your school?
•2. What nonliving things are found in your school?
•3. Into what large groups are the students in your school
divided?
•4. Into what smaller groups are these large groups divided?
•5. Are these groups ever divided into even smaller groups? If so,
what are these groups?
What is Ecology?
• Study of interactions
among
1. Organisms (LivingLiving)
2. Organisms and their
environment (LivingNonliving)
Species- a group of similar
organisms that can breed and
produce fertile offspring.
3-2 Ecological Levels of Organization
Section 3-1
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Section:
Levels of Organization
• Individual- one
organism (living)
• Ex a moose
Levels of Organization
• Population- groups of
individuals that belong
to the species and live
in the same area.
(living-living same
species)
• Ex many moose
Levels of Organization
• Community- groups of
different populations
(more than one
population or different
groups of species)
Ex many groups of moose
beavers, trees, grass (all
living)
Levels of Organization
• Ecosystem- all
organisms in a
particular area along
with the nonliving.
(living and nonliving)
Ex many groups of
moose beavers, trees,
grass, rocks, water,
mountains
Levels of Organization
• Biome- group of
ecosystems that have the
same climate and similar
dominant communities
• Biomes: tropical rain forest,
tropical dry forest, tropical
savannah, temperate grassland,
desert, temperate woodland and
shrubland, temperate forest,
northwestern coniferous forest,
boreal forest (taiga), tundra,
mountains and ice caps
Levels of Organization
• Biosphere- all of the
planet where life
exhists, includes land,
water, and, air
• Life extends 8 km up
and 11 km below the
surface
What shapes an ecosystem?
• Biotic factorsbiological (living)
influences on
ecosystem
• Abiotic factorsnonliving influences
on ecosystems
• Ex. Interactions
between organisms,
predation, symbiosis,
etc.
• Ex. Temperature,
precipitation, nutrient
availability, soil type,
sunlight.
Biotic- anything living
Abiotic- anything non-living
Habitat vs. Niche
• Habitat- an area where an organism lives
• Niche- full range of physical and biological
conditions in which an organism lives and the way
in which the organism uses those conditions.
Includes where in the food chain it is, where an
organism feeds
• Habitat is like an address in an ecosystem and a
niche is like an occupation in an ecosystem.
Community Interactions
• when organisms live together in an ecological community
they interact constantly.
• Three types of interactions
– Competition
– Predation
– Symbiosis
Competition- competing for
resources
• occurs due to a limited
number of resources
• Resource- any necessity
of life. water, nutrients,
light, food.
• Competitive exclusion
principle- no two species
can occupy the same niche
in the same habitat at the
same time
Predation
• Predation- when an
organism captures and
feeds on another
organism.
• Predator- hunter
• Prey- hunted
Symbiosis
• Symbiosis- any relationship where two
species live closely together. (3 types)
– Mutualism
– Commensalism
– Parasitism
Symbiosis
• Mutualism- both
species benefit from a
relationship.
• Lichens (fungus and
Algae)
One example is the lichens, little non-descript patches of stuff you see growing on rocks and tree bark. This is a symbiosis,
consisting of a fungus and an alga. The fungus provides a protective home for the algae, and gathers mineral nutrients from
rainwater and from dissolving the rock underneath. The alga gathers energy from the sun. There are thousands of species of
lichen in the world; actually thousands of species of fungi with just a few species of algae which can form a partnership with
almost any of them.
Symbiosis
• Commensalism – One
member of a symbiotic
relationship benefits and
the other is neither helped
or harmed
• Ex. Holes used by bluebirds
in a tree were chiseled out
by woodpeckers after it has
been abandoned .
Symbiosis
• Parasitism- One
creature benefits and
one creature is harmed
• Ex tapeworm. Feeds in
a humans intestines
absorbing his/her
nutrients.
Energy Flow (Trophic Levels)
• Producers- make their • Consumers- get
own food
energy from
consuming producers
or other consumers
Producers
• Producers- capture
energy from sunlight
or chemicals and use
the energy to produce
food.
• Producers are
autotrophs- they
make food from their
environment
Autotrophs
• Get energy from the
sun-by photosynthesis
• Get energy without lightby chemosynthesis
Consumers
• Consumers are heterotrophs- get energy
from other organisms
Types of Consumers
• Herbivores- eat only plants
• Carnivores- eat animals
• Omnivores- eat both plants and animals
• Detritivores- eat dead matter (plants and animals)
Feeding Relationships
• Energy flows through an ecosystem in one direction
from:
–
–
–
–
1. the sun or inorganic compounds
2. To autotrophs (producers)
3. To heterotrophs (consumers)
Decomposers get energy from decomposing dead organisms
Food Chain- a series of steps in which organisms
transfer energy by eating or being eaten.
Third Level
Consumers
Second Level
Consumers
First Level (Primary)
Consumers
Food Web- A network of feeding
relationships.
(More realistic than a food chain)
Trophic levels
• Each step in a food chain
or a food web is called a
trophic level.
– Producers are the first
trophic level
– Consumers are the second,
third, or higher trophic level
• Each trophic level depends
on the one below for
energy
Third Level
Consumers
Second Level
Consumers
First Level (Primary)
Consumers
Energy Pyramid
• Only part of the energy stored in
one level can be passed to the
next- most energy is consumed
for life processes (respiration,
movement, etc., and heat is
given off)
• Only 10% of the energy
available within one trophic
level is transferred to organisms
in the next trophic level
Biomass Pyramid
• Biomass- the total
amount of living tissue
within a given trophic
level.
• A biomass pyramid
represents the amount
of potential food
available for each
trophic level in an
ecosystem.