APES Exam Study Guide best complete
solutions 2025/2025
aerobic respiration - ANSWERS a process where organic molecules (like glucose) combines with
oxygen to produce carbon dioxide and water as well as energy (ATP).
aquifer - ANSWERS porous, water-saturated layers of sand, gravel, or bedrock that can yield an
economically significant amount of water.
atmosphere - ANSWERS whole mass of air surrounding earth.
biomass - ANSWERS organic matter produced by plants and other photosynthetic producers;
total dry weight of all living organisms that can be supported to each trophic level in a food
chain or web.
biosphere - ANSWERS zone of the earth where life is found in the atmosphere, hydrosphere,
and lithosphere.
carbon cycle - ANSWERS cyclic movement of carbon in different chemical forms from the
environment to organisms and then back to the environment.
consumer (heterotroph) - ANSWERS organism that cannot synthesize the organic nutrients it
needs and gets its organic nutrients by feeding on the tissues of producers or other consumers.
,decomposer - ANSWERS organism that digests part of dead organisms and cast-off fragments
and wastes of living organisms by breaking down the complex organic molecules AND
RETURNING NUTRIENTS TO SOIL & WATER!
detritivore - ANSWERS consumer organism that feeds on detritus, parts of dead organisms, and
cast-off fragments and wastes of living organisms.
food chain - ANSWERS series of organisms in which one eats or decomposes the preceding one.
The sequence of organisms in an ecosystem through which energy is transferred.
food web - ANSWERS complex network of many interconnected food chains and feeding
relationships.
geosphere - ANSWERS the earth's immensely hot core, thick mantle comprised mostly of rock
and a thin outer crust that contains most of the earth's rock, soil, and sediment.
greenhouse effect - ANSWERS natural effect that releases heat into the atmosphere near the
earth's surface. Water vapor, carbon dioxide, ozone, and other gases in the troposphere absorb
some of the infrared radiation radiated by the earth's surface & release it as heat.
gross primary productivity - ANSWERS rate at which an ecosystem's producers capture and
store a given amount of chemical energy as biomass in a given length of time.
groundwater - ANSWERS water that sinks into the soil and is stored in slowly flowing and slowly
renewed underground reservoirs called aquifers; underground water in the zone of saturation,
below the water table.
hydrologic cycle - ANSWERS biogeochemical cycle that collects, purifies, and distributes the
earth's fixed supply of water from the environment to living organisms and then back to the
environment.
, hydrosphere - ANSWERS the earth's liquid water (lakes, rivers, ponds, ocean, underground
water), frozen water (icecaps, glaciers, permafrost), and gaseous water (water vapor in the
atmosphere).
net primary productivity - ANSWERS rate at which all plants in an ecosystem produce net useful
chemical energy; equal to the difference between the rate at which the plants in an ecosystem
produce useful chemical energy (gross primary productivity) & the rate at which they use some
of that energy through cellular respiration.
nitrogen cycle - ANSWERS cyclic movement of nitrogen in different chemical forms from the
environment to organisms and then back to the environment.
nutrient - ANSWERS any chemical an organism must take in to live, grow, and reproduce.
nutrient cycle (biogeochemical cycle) - ANSWERS natural process that recycles nutrients in
various chemical forms from the nonliving environment to living organisms & then back to the
nonliving environment.
omnivore - ANSWERS animal that can use both plants and animals as food sources.
phosphorous cycle - ANSWERS cyclic movement of phosphorous in different chemical forms
from the environment to organisms and then back to the environment.
photosynthesis - ANSWERS complex process in the cells of green plants that captures light
energy and converts it to chemical bond energy.
primary consumer (herbivore) - ANSWERS organism that feeds on some of all parts of plants or
on other producers.
solutions 2025/2025
aerobic respiration - ANSWERS a process where organic molecules (like glucose) combines with
oxygen to produce carbon dioxide and water as well as energy (ATP).
aquifer - ANSWERS porous, water-saturated layers of sand, gravel, or bedrock that can yield an
economically significant amount of water.
atmosphere - ANSWERS whole mass of air surrounding earth.
biomass - ANSWERS organic matter produced by plants and other photosynthetic producers;
total dry weight of all living organisms that can be supported to each trophic level in a food
chain or web.
biosphere - ANSWERS zone of the earth where life is found in the atmosphere, hydrosphere,
and lithosphere.
carbon cycle - ANSWERS cyclic movement of carbon in different chemical forms from the
environment to organisms and then back to the environment.
consumer (heterotroph) - ANSWERS organism that cannot synthesize the organic nutrients it
needs and gets its organic nutrients by feeding on the tissues of producers or other consumers.
,decomposer - ANSWERS organism that digests part of dead organisms and cast-off fragments
and wastes of living organisms by breaking down the complex organic molecules AND
RETURNING NUTRIENTS TO SOIL & WATER!
detritivore - ANSWERS consumer organism that feeds on detritus, parts of dead organisms, and
cast-off fragments and wastes of living organisms.
food chain - ANSWERS series of organisms in which one eats or decomposes the preceding one.
The sequence of organisms in an ecosystem through which energy is transferred.
food web - ANSWERS complex network of many interconnected food chains and feeding
relationships.
geosphere - ANSWERS the earth's immensely hot core, thick mantle comprised mostly of rock
and a thin outer crust that contains most of the earth's rock, soil, and sediment.
greenhouse effect - ANSWERS natural effect that releases heat into the atmosphere near the
earth's surface. Water vapor, carbon dioxide, ozone, and other gases in the troposphere absorb
some of the infrared radiation radiated by the earth's surface & release it as heat.
gross primary productivity - ANSWERS rate at which an ecosystem's producers capture and
store a given amount of chemical energy as biomass in a given length of time.
groundwater - ANSWERS water that sinks into the soil and is stored in slowly flowing and slowly
renewed underground reservoirs called aquifers; underground water in the zone of saturation,
below the water table.
hydrologic cycle - ANSWERS biogeochemical cycle that collects, purifies, and distributes the
earth's fixed supply of water from the environment to living organisms and then back to the
environment.
, hydrosphere - ANSWERS the earth's liquid water (lakes, rivers, ponds, ocean, underground
water), frozen water (icecaps, glaciers, permafrost), and gaseous water (water vapor in the
atmosphere).
net primary productivity - ANSWERS rate at which all plants in an ecosystem produce net useful
chemical energy; equal to the difference between the rate at which the plants in an ecosystem
produce useful chemical energy (gross primary productivity) & the rate at which they use some
of that energy through cellular respiration.
nitrogen cycle - ANSWERS cyclic movement of nitrogen in different chemical forms from the
environment to organisms and then back to the environment.
nutrient - ANSWERS any chemical an organism must take in to live, grow, and reproduce.
nutrient cycle (biogeochemical cycle) - ANSWERS natural process that recycles nutrients in
various chemical forms from the nonliving environment to living organisms & then back to the
nonliving environment.
omnivore - ANSWERS animal that can use both plants and animals as food sources.
phosphorous cycle - ANSWERS cyclic movement of phosphorous in different chemical forms
from the environment to organisms and then back to the environment.
photosynthesis - ANSWERS complex process in the cells of green plants that captures light
energy and converts it to chemical bond energy.
primary consumer (herbivore) - ANSWERS organism that feeds on some of all parts of plants or
on other producers.
