AS Marine Science - Chapter 3: Interactions in Marine Ecosystems

Chlorophyll

a pigment found in plants and algae that is used to absorb sunlight for photosynthesis

photosynthesis

the process of using light energy to synthesize glucose from carbon dioxide and water to produce chemical energy

carbohydrate

organic compounds occurring in living tissues that contain carbon, hydrogen and oxygen (i.e. starch, cellulose and sugars; can be broken down in the process of respiration to release energy

consumer

an animal which feeds on other organisms to gain energy from food

algal bloom

a rapid increase in a population of algae

community

all the different interacting populations in one habitat at the same time

mutualism

a relationship between two organisms of different species where both organisms benefit

predation

a relationship between two species where a predator hunts, kills and eats a prey animal

parasitism

a relationship between two organisms where the parasite obtains benefits at the expense of the host

competition

a relationship between two organisms where both species are negatively affected as they are trying to use the same resources

symbiosis

a relationship between two or more organisms of different species which live in close proximity to each other

commensalism

a relationship between two organisms where one organism benefits and the other is neither harmed not benefitted

ectoparasite

a parasite that lives on the outside of its host

endoparasite

a parasite that lives within the body of its host

phoresis

a commensal relationship where one organism attaches itself to another in order to travel

autotroph

An organism that can capture energy from sunlight or chemicals and use it to produce carbohydrates from simple inorganic molecules like carbon dioxide; also called a producer.

chemosynthesis

the process of creating organic compounds using energy derived from reactions with inorganic compounds

heterotroph

an organism that cannot make its own food and instead relies on consuming other organisms

examples of heterotrophs

all animals, fungi and protozoans; most bacteria

primary productivity

the rate of production of new biomass through photosynthesis or chemosynthesis

food chain

series of steps displaying feeding relationships in an ecosystem in which organisms transfer energy by eating and being eaten; linear

herbivore

an animal which feeds only on producers (plants, algae, phytoplankton)

carnivore

an animals which feeds on other animals

predator

an animal which hunts, kills and eats other animals

prey

an animal which is eaten by predators

omnivore

an animal which feeds on producers and other animals

decomposer

bacteria and fungi which breakdown dead organic matter and release the nutrients back into the environment

food web

a way to show all of the different feeding relationships present in an ecosystem

biomass

the mass of living material in an area

ways of measuring biomass

as dry mass (all water removed) or wet mass (with water present)

trophic level

the position an organism occupies in the food chain or web

apex predator

an organism at the end of the food chain which has no natural predators

photoautotroph

an organism which is able to use light energy to synthesize organic compounds

grazer

Organism that eats small portions of other organisms throughout the day

planktivore

carnivorous fish that eat plankton

carnivorous fish that eat other fish

piscivores

photic zone

surface layer of the ocean that receives sunlight

chemoautotroph

organism which is able to use chemical energy to synthesize organic materials

extremophile

organism that is adapted to survive extreme temperatures, pressure, salinity or pH

respiration

the process by which all living things release energy from the food by oxidizing glucose

compensation point

the light intensity at which the rate of photosynthesis and the rate of respiration are equal

eutrophication

the process by which a body of water becomes enriches in dissolved nutrients that stimulate the growth of producers, usually resulting in the depletion of oxygen

secondary production depends on

- the biomass available in the producers

- the amount of energy lost through R by consumers

- the amount of energy lost in waste products

energy transfer formula

C = P + R + F + U

pyramid of numbers

representation of the number of individual organisms in each trophic level of an ecosystem

pyramid of biomass

illustrates the relative amount of living organic matter available at each trophic level in an ecosystem

pyramid of energy

A pyramid that shows the total amount of energy available at each trophic level.

nutrient cycles

processes that that move nutrients back and forth between the biotic and abiotic environment

nutrient

a chemical that provides what is needed for organisms to grow, repair damaged cells and tissues, release energy of for their own metabolism

assimilation

the conversion of a nutrient into a useable form that can be incorporated into the tissues of an organism

primary producers

organisms that produce biomass from inorganic compounds

polymers

A large molecule consisting of many identical or similar molecular units, called monomers, covalently joined together in a chain.

monomers

the smallest unit of a polymer

starch

a carbohydrate made from chains of glucose molecules joined together

cellulose

an important component of plant cell walls which is made from many straight chains of glucose held together by hydrogen bonds

lipid

Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.

fatty acid

lipid molecules that are a major constituent of triglycerides and phospholipids

triglyceride

a type of lipid which is made from a glycerol molecule joined to three fatty acid chains

hydrophobic

a molecule without a charge that repels water molecules

residence time

The average time a given particle will stay in a given system

excretion

the process of eliminating the waste formed from the chemical reactions within living cells

sinks

an area where there is a net loss of material (i.e. more CO2 dissolves into ocean that leaves it)

sources

an area where there is a net gain of material (i.e. more CO2 diffuses into atmosphere than dissolves into ocean)

marine snow

Particles of organic material that fall from surface waters to the deeper ocean

carbonic acid

a weak acid made of carbon dioxide dissolved in water

carbonic acid formation

H2O + CO2 →H2CO3

sedimentary rocks

rock formed by the deposition of particles on the ocean floor

marine uplift

A process by which the floor of the ocean rises, possibly to the extent that it is no longer beneath the water

fossil fuels

buried organic materials from dead plants and animals which have been converted into oil, coal or natural gas by exposure to heat and pressure in the Earth's crust