Transcript Ecology Notes - Katy Independent School District

RELATIONSHIPS IN
MARINE ECOSYSTEMS
Energy Flow
•
Sunlight – main energy source for life on Earth.
•
Goes through ecosystem in one direction, from
sun or inorganic compounds, to autotrophs
(producers), and then to various heterotrophs
(consumers)
•
Producers: autotrophs (plants, some algae, and
certain bacteria) capture energy from
sunlight or chemicals and make their own food
•
Consumer- all heterotrophs: they rely on food
containing the sun’s energy (producers)
Trophic Levels
•
Each step in a food chain or web
•
Producers are on the 1st trophic level and
consumers are 2nd or higher levels. Each
consumer depends on trophic level below
it for energy.
Feeding Relationships
•
Food Chain: Simple model showing
the steps in which organisms
transfer energy by eating and being
eaten. Shows only one pathway of
energy
•
Food Web: All feeding relationships
among various organisms in an
ecosystem. Form a network of
complex interactions and show all
pathways of energy
•
Predation – one organism captures
and feeds on another organism.
(predator/prey)
• Predator – does the killing
• Prey – one that is killed
FOOD WEBS
Symbiosis: Two species live closely together
Type of relationship
Mutualism
Commensalism
Parasitism
= 1 species
Species
harmed
Species
benefit
Species
neutral
Mutualism: Beneficial to Both species
•
Examples:
•
boxing crab and sea anemone
•
cleaner shrimp
•
lichens on rocks
Commensalism: One benefits and other is not
helped nor harmed
•
Examples:
•
Pilot fish and sharks
•
Emperor shrimp and sea
cucumber
•
Polar bears and cyanobacteria
Parasitism: One organisms lives on or inside
another and harms it
•
Examples:
•
Lampreys/leaches
•
isopods
•
trematodes