all Earth’s organisms and the nonliving environment with which they interact
The biosphere is best defined as ________.
the soil being loose and to nutrient cycling, allowing new grass roots to grow and prosper
Prairie dog activities probably contribute to ________.
In an aquatic ecosystem experiencing eutrophication, levels of dissolved macronutrients ________ and dissolved oxygen levels ________.
A system stabilized by negative feedback, with opposing processes offsetting each other, is said to be in ________.
excess nutrients from fertilizers
The eutrophication that has taken place in Chesapeake Bay, the Gulf of Mexico, and other locations appears to be due to ________.
stabilize the ecosystem
Negative feedback processes tend to function within ecosystems to ________.
sum of all the planet’s living organisms and the abiotic portions of the environment with which they interact
The biosphere consists of the ________.
are more common in natural systems altered by human actions
Positive feedback loops _______.
its role as a habitat for other organisms in the ecosystem
Which of the following would be considered an emergent property of a tree?
characteristics that are not evident in the system’s individual components but are evident only by looking at the whole operating system
What does the term emergent properties describe?
The structural sphere of Earth that is best described as the rocks and sediment is the ______.
positive feedback loops
Which of the following would destabilize an ecosystem?
are required in large amounts for organisms to survive
transitional zones between ecosystems
Ecotones are the ________.
energy flows through an ecosystem; nutrients cycle
Which best describes how energy and nutrients work in an ecosystem?
Dead zones are reversible if nutrient pollution input to a system is reduced.
Which of the following statements about dead zones is correct?
The largest pool of carbon in the carbon cycle is
in the form of ice
The majority of Earth’s fresh water exists ________.
by producing synthetic fertilizers and applying them to crops, lawns, and parks
Humans have dramatically altered the rate of nitrogen fixation into forms usable by autotrophs ________.
underground water reservoirs
Aquifers are ________.
warm temperatures and strong winds
Which two factors can speed up the process of evaporation?
Which type of feedback loop acts to resist change in natural systems, thereby enhancing system stability and promoting conditions favorable for life?
through the process of transpiration
How do plants contribute to the water cycle?
The process that makes nitrogen available to plants by mutualistic and free-living bacteria is called __________.