Study Guide
Ecology and Biomes Test
Ecology - The study of the interactions between living and non-living factors in an environment.
biotic - all living factors in an environment; animals, plants, bacteria
abiotic - all non-living factors in an environment; weather, sun, water, temperature
Symbiosis - a close long-term association between two or more species.
3 types of symbiotic relationships
mutualism - symbiotic relationship in which both organisms benefit ex: the clownfish and sea anemone.
Sea anemone provides protection for the fish and the fish provides scrapes of food for anemone.
parasitism – symbiotic relationship in which one organism benefits while the other is harmed ex:
heartworms in dogs, fleas and ticks on animals.
commensalism – symbiotic relationship in which one organism benefits and the other is unaffected
ex: shark and remora. Remora benefits from feeding off sharks scrapes, protection and transportation, the
shark is not affected.
Food chain – a diagram that shows how energy flows from food molecules from one organism to the next.
Energy from sun
producer
Producer
herbivore
Herbivore
carnivore
Carnivore
scavenger
Scavenger
Food web - a complex diagram showing the many energy pathways in a real ecosystem
Producers: grass and trees
Herbivores: a type of consumer that eats plants ex: rabbit, deer,
grasshopper, chipmunk
Carnivores: a type of consumer that eats animals ex: fox, owl, eagle
Omnivore: a type of consumer that eats plants and animals ex: humans
Scavenger: a type of consumer that eats remains of dead organisms ex:
vulture (not shown in picture)
Energy Pyramid - is a diagram shaped like a triangle
that shows the loss of energy at each level of the
food chain.
-Producers are the plants that convert sunlight
energy into chemical energy in sugar
-Primary Consumers or herbivores eat the producers
-Secondary consumers or carnivores eat the primary
consumers.
-Tertiary consumers eat secondary consumers. If
there were as many tertiary consumers as the
number of producers then there would not be
enough food for all the higher level consumers.
Carbon Cycle – The diagram to the left represents the carbon cycle.
Every living thing is made up of carbon and carbon plays an important
role in the cells of all living things.
Carbon enters the environment by:
 Decomposing of dead plants and animals
 Respiration of plants and animals
 Burning of fossil fuels
If too much carbon enters the atmosphere in a form that is not useable
(gas), then it accumulates and causes an imbalance in the
environment. Some scientists believe carbon emissions are the major
cause of our ocean and land temperatures increasing. Scientists call
this global warming.
The Nitrogen Cycle All living things need nitrogen. Plants get the nitrogen they
need from the ground. Nitrogen-fixing bacteria change the
nitrogen from the atmosphere into a form that plants can use.
Nitrogen gets into the environment by:
Animal waste
Fertilizers
Decaying of plants and animals
Nitrogen enters waterways and causes algae blooms. This
increase in plant growth depletes oxygen from the water and
other animals and plants die because they do not get the
oxygen they need to survive and grow.
The Water Cycle – evaporation, condensation and precipitation are three components of this cycle.
MAJOR CHARACTERISTCS OF BIOMES
Rainforest
Warm, very rainy, near equator, most biologically diverse animals include:
poison dart frog, orangutan, monkey
Tundra
Located at far Northern or Southern latitudes (or at high elevations).
Permafrost, very cold, thin soil. Animals include: caribou, arctic fox, polar bear
Coniferous forest
Evergreen (coniferous) trees, long cold winters, short cool summers. Animals
include: red fox, moose, owl, hare.
Temperate deciduous forest
Four seasons, deciduous trees, moderate temperatures. Animals include:
eagle, deer, bear, and squirrel.
Temperate grassland
Grasses, few trees, four seasons. Animals include: coyotes, bobcats, and bison.
Desert
Very hot days, cool nights, very dry, little rainfall. Animals include: lizard, snake.
Tropical savanna
Dry season and rainy season, located near the equator, tall grasses. Animals
include: hawks, lions, leopards, and zebra.
Marine
Salt water Animals include: blue whale, sea otters, fish.
Estuary
Salt and freshwater come together ex: Chesapeake bay . Animals include:
crab, salmon, heron.
Habitat – the environment where an organism lives.
Niche – an organisms way of life and its relationships with its abiotic (nonliving) and biotic (living) environments.
All organisms need food, shelter, living space, and water to survive. These resources are called limiting factors.
The availability of these limiting factors have an affect on the number of organisms that can live in an area at the
same time. The carrying capacity is the largest population that an environment can support.
Competition – two or more species or individuals trying to use the same limited resource.
Organism is a member of a species ex: a wolf
Population is a group individuals of the same
species living together in the same area at the same
time ex: pack of wolves
Community are all of the populations of
different species living together in the same area at
the same time. Ex: wolves and bears
Ecosystem all nonliving (abiotic) and living
(biotic) factors in an environment ex: bear, wolves,
ice, weather
Biomes- a large region characterized by a specific type
of climate and certain types of plant and animal
communities
Biosphere the part of the Earth on which
life exists and includes all of the different ecosystems.