Ecology is the scientific study of the interactions between organisms and their environments. It reveals the interrelationships between living (biotic) and nonliving (abiotic) parts of the world. Key concepts in ecology include the biosphere, biotic factors, abiotic factors, levels of organization (organism, population, community, ecosystem, biome, biosphere), habitats, niches, and symbiosis (commensalism, mutualism, parasitism). Ecology combines information from various sciences to understand these relationships.

1. Chapter 2 - Principles of
Ecology

2. 2.1 Organisms &
Their Relationships

3. What is Ecology?
Scientific study of interactions between
organisms and their environments
Reveals interrelationships between living
(biotic) and nonliving (abiotic) parts of
the world
Combines information from math,
chemistry, physics, geology, other
branches of biology

4. Ecology Video

5. Biosphere
bio = life, sphere = area
the portion of Earth that supports life
extends from high in the atmosphere
to the bottom of the ocean

6. Biotic factors
bio = life, tic = relating to
all living organisms that inhabit an
environment
examples: animals (humans),
Plants, Protists, Bacteria, fungi

7. Abiotic factors
a = not
nonliving parts of the environment
that effect living things
examples: air currents, water
currents, temperature, water pressure,
rocks, sand, soil, moisture, light

8. Abiotic Factors Video

9. Levels of Organization (p. 36)
Organism
Population
Community
Ecosystem
Biome
Biosphere

10. Organisms
 an individual living thing

11. Populations
 group of organisms of one species living in
the same place at the same time that
interbreed, compete with one another for
food, water, mates, and other resources; a
change in one population will affect other
populations
No population of organisms of one
species lives independently of other
species.

12. Communities
 made up of several
populations interacting with
each other

13. Ecosystem
 all the biotic and abiotic factors in an
area
 the interactions among the
populations in a community and the
community’s physical surroundings,
or abiotic factors

14. Terrestrial Ecosystems
located on land
examples:
Forests
Meadows
Desert

15. Aquatic
Ecosystems
fresh water ecosystems
 examples: ponds, lakes, and streams
salt water (marine) ecosystems
 examples: oceans, seas, large lakes
“Great Salt Lake”

16. Biome
Ecosystems that share the
same climate and have similar
types of communities
Ex. Marine biome

17. Biosphere
the entire planet and all its living
and nonliving parts and how
everything interacts

18. Habitat
Place where an organism lives its
life
Can change or even disappear
Organisms must adapt to the
changes or they will die.

19. Niche p. 38
the role a species plays in a
community
although several species may
share a habitat, the food, shelter,
and other resources are divided
into separate niches

20. Niche examples:
coyotes in a grassland community help
keep down the rodent population
fungi in a forest helps breakdown of
organic matter contained in the bodies
of dead organisms to recycle nutrients

21. Symbiosis
“living together”
the relationship in which there is a
close and permanent association
between organisms of different
species
different kinds of symbiosis:

22. Commensalism
one species benefits and the
other species is neither harmed
nor benefited

23. Commensalism
example: large trees such as
oaks provide a habitat for
Spanish moss

24.  Remoras live very close to sharks. The shark
does not bother the remora, but the remora
eats the leftover food the shark drops or
does not eat.

25. Mutualism
both species benefit
Ants and Acacia
Tree

26. Mutualism
 An unidentified crab that carries a venomous
sea urchin for protection. The crab uses its
rear legs to hold the urchin in place. The
urchin receives transportation.

27.  The Sponge Crab is wearing a "hat"
that consists of a living sponge colony.
The sponge gains transportation while
the crab gains a disguise.

28.  The Tomato Anemone Fish lives among
the Sea Anemone. It gains protection
from predators while the anemone gains
dinner.

29. Parasitism
one species is harmed, but
usually does not kill the host
examples: tapeworms,
roundworms, ticks, fleas

30.  Isopods are crustaceans, some of which are
parasites. Isopods known as "fish lice"
attach themselves to their host and feed on
its body fluids.