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The characteristic number of protons per atom of an element used as an identifying attribute.
The smallest unit of matter that has the characteristics of an element; consists of three main types of subatomic particles: protons neutrons and electrons.
The populations of plants animals and microorganisms living and interacting in a certain area at a given time.
The circulation and reutilization of carbon atoms especially via the process of photosynthesis and respiration.
Places of carbon accumulation such as in large forests (organic compounds) or ocean sediments (calcium carbonate); carbon is thus removed from the carbon cycle for moderately long to very long periods of time.
The process in which a cell breaks down sugar or other organic compounds to release energy used for cellular work; may be anaerobic or aerobic depending on the availability of oxygen.
Conservation Of Matter
In any chemical reaction matter changes form; it is neither created nor destroyed.
An organism that obtains energy and nutrients by feeding on other organisms or their remains.
The scientific study of relationships between organisms and their environment. It is concerned with the life histories distribution and behavior of individual species as well as the structure and function of natural systems at the level of populations communities and ecosystems.
A specific biological community and its physical environment interacting in an exchange of matter and energy.
A molecule composed of one kind of atom; cannot be broken into simpler units by chemical reactions.
First Law Of Thermodynamics
States that energy is conserved. It is neither created nor destroyed underneath normal conditions.
A linked feeding series; in an ecosystem the sequence of organisms through which energy and materials are transferred in the form of food from one trophic level to another.
A form of energy transferred from one body to another because of a difference in temperatures.
The natural process by which water is purified and made fresh through evaporation and precipitation. The cycle provides all the fresh water available for biological life.
Forms of a single element that differ in atomic mass due to a different number of neutrons in the nucleus.
Energy contained in moving objects such as a rock rolling down a hill the wind blowing through the trees or water flowing over a dam.
All the energy and matter exchanges that occur within a living cell or organism; collectively, the life processes.
Complex molecules organized around skeletons of carbon atoms arranged in rings or chains; includes biomolecules molecules synthesized by living organisms.
A value that indicated the acidity or alkalinity of a solution on a scale of 0-14, based on the proportion of H+ ions.
The movement of phosphorus atoms from rocks through the biosphere and hydrosphere and back to rocks.
The biochemical process by which green plants and some bacteria capture light energy and use it to produce chemical bonds. Carbon dioxide and water are consumed while oxygen and simple sugars are produced.
Stored energy that is latent but available for use. A rock poised at the top of a hill or water stored behind a dam are examples.
An organism that synthesizes food molecules from inorganic compounds by using an external energy source; most producers are photosynthesis.
The synthesis of new organic material. That done by green plants using solar energy is called primary productivity.
Second Law of Thermodynamics
States that with each successive energy transfer or transformation in a system, less energy is available to do work.
A population of morphologically similar organisms that can reproduce sexually among themselves but that cannot produce fertile offspring when mated with other organisms.
The chemical and physical reactions by which sulfur moves into or out of storage and through the environment.
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