Organisms usually favor a
of food, which is why a
simple food chain is usually
rare.
Food Web
• Food web -shows all of the different
possibilities of energy flow between different
organisms.
• Diagram that shows
the feeding
relationships
between organisms
in an ecosystem
The green arrows show how energy moves when one
organism eats another. Most consumers eat a variety of
foods and can be eaten by a variety of other consumers.
DO NOW – Match the term with
the definition.
1.
2.
3.
4.
5.
A. Organisms that eat only meat
Herbivores E
B. Another word for heterotrophs
Consumers B
C. All of the populations that live
Carnivores A
in the same habitat & interact
Community C with one another
EcosystemD D. A community of organisms and
their abiotic environment
E. Organisms that eat only
producers
Energy Pyramid
• Energy pyramid shows
an ecosystem’s loss of
energy.
• The most amount of
energy is found at the
bottom of an energy
pyramid.
Energy Pyramid
• As you travel up the pyramid there is less
energy left from the original source.
• Less energy is available at higher levels
because only energy stored in the tissues of
an organism can be transferred to next level.
Energy Pyramids
The pyramid represents energy. As you can see, more
energy is available at the base of the pyramid than at its top.
Recap Questions
• What are the 3 main groups that obtain
energy?
Producers, Consumers, Decomposers
• What are organisms that get energy by
breaking down dead organisms?
Decomposers
• What are organisms that make their own food
using sunlight during photosynthesis?
Producers
Recap Questions
• What are organisms that eat other organisms?
Consumers
• What are the 4 types of consumers?
Herbivore, Carnivore, Omnivore, Scavenger
• What is a diagram that shows how energy in
food flows from one organism to another? ]
Food Chain
• What shows all of the different possibilities of
energy flow between different organisms?
Food Web
Chapter 1, Section 3:
Types of Interactions
Habitat
• An organism’s habitat is the area in
which it lives.
•
Example: A frog lives in a pond
Niche
• The organism’s way of life, is called
their niche.
• This includes their habitat, food, and
the abiotic factors that affect them
such as temperature and weather.
Interactions with the Environment
• Populations affect every other population
• Most living things produce more offspring than
will survive (ex: frog eggs)
• Biotic and abiotic factors affect survival rate
and controls the size of the population
Interactions with the Environment
• Populations cannot grow without resources.
– There is a limited amount of resources such as
food, water, living space.
• Limiting Factors - a resource that is so
necessary that it limits the size of the
population.
• Any resource can be a limiting factor!
Limiting Factors
Carrying Capacity
• The largest population that an environment
can support at any given time.
• When a population grows
larger than carrying capacity,
limiting factors cause
individuals to leave or die off.
**The population will eventually return to a size
that the environment can support**
pd 2 starts here
Interactions between Organisms
• Four main ways that species and individuals
affect each other:
1. Competition
2. Predators and prey
3. Symbiotic Relationships
4. Co-evolution
1.) Competition
• When 2 or more individuals or populations try
to use the same resource.
• Resources have a limited supply, therefore the
use by one decreases the availability for
others.
• Happens within populations or between
populations
2.) Predators and Prey
• Prey – is an organism that is eaten
o Have methods & abilities to keep from being eaten
•
•
•
•
Run
Travel in groups
Camouflage or Coloration
Poisonous
• Predator – is an organism that eats the prey
o They have methods to catch their prey
• Speed
• Ambush
• Coloration
Camouflage
• Camouflage blending in with
the background
Defensive Chemicals
–Skunks
–Bees
–Wasps
–Frogs
Warning Colors
• Warning coloration - colors that associate with
pain or illnesses.
– Bright red, yellow, orange, black and white
3.) Symbiosis
• Relationship in which two different organisms
live in close association with each other.
• Can benefit from, be unaffected by or harmed
by the relationship.
• 3 Groups:
– Mutualism
– Commensalism
– Parasitism
Mutualism
• Symbiotic relationship in which both
organisms benefit
• ++
• Examples:
– Bacteria in your
intestines
– Coral and algae
Commensalism
• Symbiotic relationship in which one organism
benefits and the other is unaffected.
•+
0
• Example:
– Sharks and remoras
(remoras “hitch a ride”
and feed on scraps left
by sharks and sharks are
unaffected)
Parasitism
• Symbiotic relationship in which one
organism benefits and one is harmed.
(+ -)
 Parasite = organism that benefits
 Host = organism that is harmed
• Parasite gets nourishment from host while
host is weakened or sometimes killed.
• Example:
– Ticks, tapeworms, tomato hornworm, etc
4.) Coevolution
• The evolution of two species that is due
to mutual influence, often in a way that
makes the relationship more beneficial
to both species.
• Relationships between organisms change
over time and interactions can change
the organism
• Takes place between any organisms that
live close together, but happens over
long periods of time
Coevolution
&
Flowers
• Pollination is necessary for reproduction
of plants
• Pollinator- Organism that carries pollen
from one flower to another.
– Example: Bees, bats, hummingbirds, etc
• Flowers have changed to attract
pollinators
– Example: Color, odor or nectar
Recap Questions
• What is a resource that is so necessary that it
limits the size of the population?
Limiting Factor
• What is the largest population that an
environment can support at any given time?
Carrying Capacity
• What type of interaction is it when an
organism gets eaten by another organism?
Predator and Prey
Recap Questions
• What type of interaction is it when 2 or more
individuals or populations try to use the same
resource?
Competition
• Skunks, bees, frogs fend off their predators by
what?
Defensive Chemicals
• What type of interaction is it when two different
organisms live in close association with each
other?
Symbiosis