IB ESS Review
model - ANSWER...-a simplified description designed to show the structure or working
of an object, system or concept.
open system - ANSWER...-type ***** in which both matter and energy are exchanged
with its surroundings
closed system - ANSWER...-type ****** in which energy but not matter is exchanged
with its surroundings
Gaia hypothesis - ANSWER...-developed by James Lovelock, compares the Earth to a
living organism in which feedback mechanisms maintain equilibrium
isolated system - ANSWER...-type ******** in which neither energy nor matter is
exchanged with its surroundings.
system - ANSWER...-an assemblage of parts and their relationships between them,
which together constitute an entity or whole
positive feedback - ANSWER...-that tends to amplify or increase change leads to
exponential deviation away from an equilibrium
negative feedback - ANSWER...-that tends to damp down, neutralize or counteract any
deviation from an equilibrium, promoting stability
biosphere - ANSWER...-The part of the earth inhabited by organisms, that is, a narrow
zone (a few kilometers in thickness) in which plants and animals exist. It extends from
the upper part of the atmosphere down to the deepest part of the Earth's crust to which
living organisms venture.
steady state equilibrium - ANSWER...-characteristics of open systems where there are
continuous inputs and outputs of energy and matter but the system as a whole remains
more or less constant.
society - ANSWER...-arbitrary group of individuals who share some common
characteristic such as geographical location, cultural background, historical influence,
religious perspective, value system and so on.
entropy - ANSWER...-a measure of the amount of disorder, chaos or randomness in a
system the greater the disorder the higher the level of this.
, abiotic factors - ANSWER...-non living factor that may influence an ecosystem. Ex:
temperature, pH, Salinity
biotic factors - ANSWER...-living biological factors that may influence an organism or
ecosystem. Ex: Predation disease, competition
Principle of Competitive exclusion - ANSWER...-2 species competing for the same
resources cannot coexist in the same community.
Pyramid of Productivity - ANSWER...-flow of energy through a trophic level, only 10% of
pervious level available to the next level. Measured in g/m2
Gross Productivity (GP) - ANSWER...-total gain in energy or biomass per unit area per
unit time. Could be through primary producers or absorption in consumers.
Net Primary Productivity (NPP) - ANSWER...-GP-respiration= gain in energy per unit
area per unit of time after allowing for respiratory losses.
Gross Primary Productivity (GPP) - ANSWER...-total gain in energy per unit area per
unit time fixed by photosynthesis in green plants.
Net Primary Productivity - ANSWER...-Gain by producers in energy or biomass per unit
area per unit time remaining after allowing for respiratory losses (R) potentially available
to consumers. =GPP-R
Net Secondary Productivity (NSP) - ANSWER...-gain by producers in energy or
biomass per unit area per unit of time remaining after allowing for respiratory losses.
=GSP-R
Gross Secondary Productivity (GSP) - ANSWER...-the total gain in energy or biomass
per unit area per unit of time through absorption (excluding foecal loss) food eaten -
foecal loss
biome - ANSWER...-collection of ecosystems sharing similar climactic conditions for
example tundra, desert, rainforest
diversity - ANSWER...-a generic term for heterogeneity. It may refer to the
heterogeneity or a species or heterogeneity or genentic heterogeneity.
K-strategist - ANSWER...-species that concentrate their reproductive investment in
small number of offspring thus increasing their survival rate
r-strategist - ANSWER...-species that tend to spread their reproductive investment
among a large number of offspring so that they are well adapted to colonize new
habitats rapidly and make opportunistic use of short lived resources.
model - ANSWER...-a simplified description designed to show the structure or working
of an object, system or concept.
open system - ANSWER...-type ***** in which both matter and energy are exchanged
with its surroundings
closed system - ANSWER...-type ****** in which energy but not matter is exchanged
with its surroundings
Gaia hypothesis - ANSWER...-developed by James Lovelock, compares the Earth to a
living organism in which feedback mechanisms maintain equilibrium
isolated system - ANSWER...-type ******** in which neither energy nor matter is
exchanged with its surroundings.
system - ANSWER...-an assemblage of parts and their relationships between them,
which together constitute an entity or whole
positive feedback - ANSWER...-that tends to amplify or increase change leads to
exponential deviation away from an equilibrium
negative feedback - ANSWER...-that tends to damp down, neutralize or counteract any
deviation from an equilibrium, promoting stability
biosphere - ANSWER...-The part of the earth inhabited by organisms, that is, a narrow
zone (a few kilometers in thickness) in which plants and animals exist. It extends from
the upper part of the atmosphere down to the deepest part of the Earth's crust to which
living organisms venture.
steady state equilibrium - ANSWER...-characteristics of open systems where there are
continuous inputs and outputs of energy and matter but the system as a whole remains
more or less constant.
society - ANSWER...-arbitrary group of individuals who share some common
characteristic such as geographical location, cultural background, historical influence,
religious perspective, value system and so on.
entropy - ANSWER...-a measure of the amount of disorder, chaos or randomness in a
system the greater the disorder the higher the level of this.
, abiotic factors - ANSWER...-non living factor that may influence an ecosystem. Ex:
temperature, pH, Salinity
biotic factors - ANSWER...-living biological factors that may influence an organism or
ecosystem. Ex: Predation disease, competition
Principle of Competitive exclusion - ANSWER...-2 species competing for the same
resources cannot coexist in the same community.
Pyramid of Productivity - ANSWER...-flow of energy through a trophic level, only 10% of
pervious level available to the next level. Measured in g/m2
Gross Productivity (GP) - ANSWER...-total gain in energy or biomass per unit area per
unit time. Could be through primary producers or absorption in consumers.
Net Primary Productivity (NPP) - ANSWER...-GP-respiration= gain in energy per unit
area per unit of time after allowing for respiratory losses.
Gross Primary Productivity (GPP) - ANSWER...-total gain in energy per unit area per
unit time fixed by photosynthesis in green plants.
Net Primary Productivity - ANSWER...-Gain by producers in energy or biomass per unit
area per unit time remaining after allowing for respiratory losses (R) potentially available
to consumers. =GPP-R
Net Secondary Productivity (NSP) - ANSWER...-gain by producers in energy or
biomass per unit area per unit of time remaining after allowing for respiratory losses.
=GSP-R
Gross Secondary Productivity (GSP) - ANSWER...-the total gain in energy or biomass
per unit area per unit of time through absorption (excluding foecal loss) food eaten -
foecal loss
biome - ANSWER...-collection of ecosystems sharing similar climactic conditions for
example tundra, desert, rainforest
diversity - ANSWER...-a generic term for heterogeneity. It may refer to the
heterogeneity or a species or heterogeneity or genentic heterogeneity.
K-strategist - ANSWER...-species that concentrate their reproductive investment in
small number of offspring thus increasing their survival rate
r-strategist - ANSWER...-species that tend to spread their reproductive investment
among a large number of offspring so that they are well adapted to colonize new
habitats rapidly and make opportunistic use of short lived resources.
