Energy flows through the environment in several predictable systems and chemical cycles because energy and mass cannot be created or destroyed. The water cycle underpins all of life. Water evaporates from reservoirs in the ocean to form clouds. Condensed water vapor then falls to earth and flows back into the oceans. Carbon is exchanged between the biosphere atmosphere, rocks, soil, and water in the carbon cycle. Nitrogen and phosphorous also have cycles, with nitrogen- and phosphorous-fixing plants playing a key role. Human activity has altered many of these cycles resulting in changes to the environment, such as the climate change resulting from increased CO2 in the atmosphere and the eutrophication of rivers and lakes as phosphorous and nitrogen fertilizers drain into the water supply.
An ecosystem is
all organisms and non-living components in one area (biotic and
The first law
of thermodynamics states that energy cannot be created or destroyed;
it can only be changed from one form to another.
Productivity (GPP) is the total amount of light energy converted to
Productivity (NPP) is the GPP minus the energy required for
The law of
conservation of mass dictates that mass cannot be created or
destroyed, therefore chemicals important to living organisms cycle
between parts of the ecosystem. These cycles are known as
The four most
significant biogeochemical cycles for living organisms are: the
water cycle, the carbon cycle, the nitrogen cycle and the
fuels removes carbon from the reservoirs and relocates the carbon to
the atmosphere in the form of CO2.
CO2 levels resulting from fossil fuel consumption have
contributed the increase in average global temperatures through the
Energy and Ecosystems
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
The book and CD package include two full length practice exams that are presented with all questions answered and explained. The author also presents detailed reviews of all test topics and includes multiple-choice and free-response questions with answers at the end of each topic's chapter.
This book includes a review of the AP Biology exam format and scoring, proven strategies for answering multiple-choice questions, and hints for tackling the essay questions. The practice tests include answers and explanations and there is also proven test-taking strategies for both the multiple choice and essay parts.