Transcript Ecology

EVERYTHING
IS
CONNECTED:
ECOLOGY
Ecology - the study of ecosystems.
Ecosystem - interactions among and
between organisms and their
environment.
Biotic factors are the living
organisms (animals, plants, fungi,
protists and bacteria).
Abiotic factors are the nonliving
things (water, air, soil, etc.).
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Levels of Organization:
Individuals - one of a species.
Populations - many of the same species.
Communities - different populations
together.
• Ecosystems - the community and the
environment together.
• Biomes - the ecosystem and the climate.
• Biosphere is the biotic and abiotic factors
together (the planet and the atmosphere).
Ecology and Evolution
• Evolution is a change in genetic
characteristics of a population from one
generation to the next
• Evolution of species occurs because of
natural selection
• Natural Selection happens when an
organism is better adapted to an
environment and therefore survives to
pass on it’s genes to the next generation
Natural Selection and Adaptations
• An adaptation is an inherited trait that
increases an organisms chance of survival
and reproduction in a certain environment
• Examples:
– Darwin’s Finches
– Deer’s fur thickness
– Snakes
Coevolution
• Organisms that evolve adaptations to
other organisms and to their physical
environments
• Example:
– Honeycreeper bird and Lobelia flower
• The Lobelia flower evolved a flower with a curved
shape to accommodate the curved beak of the
Honeycreeper
Natural vs. Artificial Selection
• Natural selection happens without
interference
• Artificial selection occurs when humans
control plant and animal breeding
• Examples:
– Domesticated animals
– Agriculture
Evolution of Resistance
• Animals and plants have developed ways
to tolerate the chemicals designed to kill
them – resistance
• Examples:
– Pesticide resistance in insects
– Antibiotic resistant bacteria
The Diversity of Living Things
• All living things are classified into groups.
• When classifying organisms we start with
the largest groups and narrow it down
from the largest group to the individual
• Domain  Kingdom  Phylum  Class
 Order  Family  Genus  Species
• We will focus on the KINGDOMS
Archaebacteria
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Single-celled prokaryote
No nucleus
Autotrophic – they make their own food
Archaea live in harsh environments and may
represent the first cells to have evolved
• Reproduce by dividing in half
• A decomposer of dead/waste materials
• Lacks peptidoglycan in their cell wall
Archaebacteria
• Thermophiles – “heat lovers.” Occur in hot,
acidic environments, such as deep sea
thermal vents. Oxidize sulfur to grow
• Halophiles – “salt lovers.” Can survive in
salt concentrations up to 32%. Found in
the Great Salt lake and the Dead Sea
• Methanogens – can survive without
oxygen. They convert carbon dioxide to
grow. Found in swamps and marshes
Bacteria
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Single-celled prokaryote
No nucleus
Autotrophic – they make their own food
Reproduce by dividing in half
Incredibly common
A decomposer of dead/waste materials
Their cell wall contains peptidoglycan
Bacteria
• Proteobacteria – common in soils and
animal intestines
• Cyanobacteria – also known as blue-green
algae
Fungi
• Most are multi-celled eukaryote, a few are
single-celled
• Cell contains a nucleus
• Heterotrophic – they get their food outside
of their body – “Different eater”
• Have a cell wall
• Absorb their food through their body
surface
• A decomposer of dead/waste materials
Fungi
• Single-celled:
– yeasts
• Multi-celled:
– molds
– mildew
– mushrooms
– rust
Protists
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Multi-celled and single-celled eukaryotes
Cells contain a nucleus
Have a cell wall
Can be autotrophic or heterotrophic
Mostly live in the water
Can be producers and consumers
Protists
• Examples:
– diatoms
– dinoflagellates
– amoebas
– paramecia
– Euglena
Plants
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Multi-celled eukaryotes
Cells contain a nucleus
Have a cell wall
Autotrophic – they make their own food
All plants are producers
Plants – lower plants
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1st land plants
No vascular tissues
Swimming sperm
Small in size and live in or near water
Examples:
– mosses
– ferns
Plants - gymnosperms
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1st woody plants
Produce seeds protected by cones
Needle-like leaves
Pollen producer
Examples:
– Pine trees
– Evergreens
Plants - angiosperms
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Flowering plants
Produce seeds in fruit
Pollen producer
Food and building staple for land animals
Examples:
– Wheat, rice, beans, oranges, lettuce, etc…
– Oak, cotton, etc…
Animals
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Multi-celled eukaryotes
Cells contain a nucleus
All animals are heterotrophic
All animals are consumers
Animals - Invertebrates
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Animals that lack a backbone
Several stages in their life cycle
Many have an exoskeleton
Largest group of animals on the planet
Examples:
– Jellyfish
– Arthopods:
• Insects
• Worms
• Mollusks
Animals - Vertebrates
• Animals that have a backbone
• Examples:
– Fish
– Amphibians
– Reptiles/Birds
– Mammals
Energy Flow
• Sunlight - the main source of energy for all
life on Earth. (In a few ecosystems, some
organisms obtain energy from a source
other than sunlight.)
• Producers make their own food from the
sun's energy through a process called
photosynthesis.
• Autotrophs (producers) plants, some
algae, and certain bacteria capture the
sun's energy to produce food for
themselves.
YOU MUST KNOW THE CHEMICAL
FORMULA FOR PHOTOSYNTHESIS:
Photosynthesis:
6CO2 + 6H2O
SUNLIGHT
C6H12O2 + 6O2
• Chemosynthesis occurs when organisms
use chemicals instead of sun light to make
food.
(Example =
Archaebacteria)
• Heterotrophs (consumers) are organisms
that rely on other organisms for their
energy and food supply.
• Energy is produced in the mitochondria of
the cell via “cellular respiration.”
• You must know the chemical formula
for cellular respiration:
Cellular Respiration:
C6H12O2 + 6O2
6CO2 + 6H2O + ATP
Types of Heterotrophs:
• Herbivores - eat plants.
• Carnivores - eat animals.
• Omnivores - eat both plant and animals.
• Detritivores - feed on plant and animal
remains and other dead matter
(scavengers).
• Decomposers bacteria and fungi that break
down organic matter into usable nutrients.
Flow of Energy
• Energy flows in one direction through an
ecosystem.
• Food Chain - a series of steps in which
organisms transfer energy by eating and being
eaten.
• Starts with the sun, then producer, 3
consumers, and finally, a decomposer puts
nutrients back into the system.
• Food Web links many food chains in an
ecosystem together.
• Energy flows in the
direction that the
arrow goes. So, the
arrow points to who
is doing the eating.
Practice Quiz !
Trophic Level
• One of the steps in a food chain or food pyramid
Trophic Levels
• Each time energy is transferred, some
energy is lost through work and waste.
• Less energy is available to organisms at
higher trophic levels.
Energy Loss Affects
Ecosystems
• Decreasing amounts of energy at each
trophic level affects number of:
– organisms at each level.
– trophic levels in ecosystem.
• Tertiary consumer (usually carnivores)
• Secondary consumer (omnivores and
carnivores)
• Primary consumer (herbivores)
• Producer (plants/autotrophs)
• Decomposers (fungi/bacteria)
• Each consumer depends on the trophic
level below it for energy. Energy flows
upward.
Recycling in the Biosphere
• Unlike Energy, which flows in one direction
through an Ecosystem, Matter is recycled.
• Matter cannot be created or destroyed, it
can only be re-arranged. It makes up living
and non-living things.
• Matter cycles throughout ecosystems over
and over again.
Succession
• A series of changes in a community in
which new populations of organisms
gradually replace existing ones
Primary succession
• Colonization of new sites by communities
of organisms – takes place on bare rock
Primary succession
• New bare rock comes from 2 sources:
1. volcanic lava flow cools and forms rock
2. Glaciers retreat and expose rock
Pioneer organisms
• The first organisms to colonize a new site
– Ex: lichens are the first to colonize lava rocks
Primary Succession
Climax community
• A stable, mature community that
undergoes little or no succession
Secondary succession
• Sequence of community changes that
takes place when a community is
disrupted by natural disaster or human
actions – takes place on existing soil
Secondary succession
• Examples:
• A fire levels portions
of a forest
• A farmer plows his
field
Secondary succession
Pond Succession
Pond Succession