ECOLOGY
Study of living & nonliving parts of an
ecosystem (environment) & how they
interact w/one another
I. 2 parts of Ecology
A. Abiotic – nonliving; ex. Sun, water,
temp., land, soil, air, humidity
B. Biotic – living; plants (producers),
animals (consumers – herbivores
(plant-eaters), omnivores (both), &
carnivores (meat-eaters) and
decomposers (bacteria, fungi)
II. Biome – large area w/
characteristic plants,
animals & conditions
A. Tropical Rainforest – warm, lots of
rain, plants/vines, insects, animals
B. Coniferous Forest – cool temps.,
conifers, (evergreens), deer, elk
C. Deciduous Forest – seasons,
deciduous trees (lose leaves in fall),
deer, raccoons; Kentucky
Deciduous & Rain Forest –
3:35
Coniferous Forest –
1:20
D. Grassland – seasons, grasses, prairie
dogs, bison
Grasslands –
1:58
E. Tundra – cold, permafrost
(permanently frozen soil), lichens,
mosses, polar bears
Tundra –
1:06
F. Desert – DRY, many are hot during day
& cold at night, cacti, reptiles,
nocturnal animals
Deserts –
1:51
G. Aquatic – marine (saltwater) &
freshwater
Marine Biomes –
2:24
III. Habitat – physical area in
which an organism lives
(smaller)
A. Niche – way of life of a species; ex.
Habitat, feeding habits, other habits,
reproductive behavior
What is the wolf’s niche?
Habitat/Niche –
2:18
B. Population – many organisms of the
same species in an area; ex. all people,
rabbits, trees, etc.
C. Community – many populations in an
area; ex. all the deer, rabbits, trees, etc.
Populations & Communities –
2:19
D. Food chains – shows energy in a
habitat; what eats what; ex. grass 
grasshopper  frog  snake  hawk
E. Food Pyramid – takes organisms from
a food chain & puts them in a pyramid
ex.
Quaternary cons.
Tertiary cons.
Secondary cons.
Primary consumer
Producer
90% energy lost at
each level due to:
Movement
Digestion
Respiration
Excretion
Reproduction
Growth
Energy
10
lost
 90
100
 900
1000
 9000
10,000
 90,000
100,000
Food Pyramid shows:
• What eats what
• Need more organisms at bottom to
support things above it
• More energy at bottom/less at top
• Lose energy (90%) at each level
Energy Pyramids –
1:05
F. Food Web – many food chains linked
together; shows interactions of all
organisms in a community
Food Web
Food Chains & Food Webs –
1:53
G. Competition – use or defense of a resource
by one individual that reduces the availability
of the resource to other individuals; ex.
Organisms compete for food, space oxygen
shelter, etc. (called limiting factors)
These two species are in
direct competition for food.
H. Relationships
1. predator – organism that feeds upon
another
2. prey – organism that is eaten
3. parasitism – one organism benefits
while the other is harmed; ex. leeches
4. commensalism – one organism
benefits & the other is unaffected; ex.
clown fish live in anemones
(remember Finding Nemo) because
other fish avoid the stinging tentacles
5. Mutualism – both benefit; ex.
flowers and bees
I. Carrying Capacity – the maximum # of
organisms an area can hold
J. Community Changes: succession –
series of changes that take place in a
community as it ages
1.Land: grasses  shrubs trees
(climax community)
2. Water: lakes ponds bogs/
swamps land
K. Biochemical Cycles
1. Water cycle: evaporation, transpiration,
precipitation, condensation
Water Cycle –
1:02
2. Oxygen/ Carbon cycle: cell respiration/
photosynthesis
Oxygen - Carbon Cycle –
1:27
3. Nitrogen cycle: Nitrogen “fixed” to
usable form (nitrogen fixation) to form
proteins
Nitrogen Cycle –
1:37