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Glossary of Chemical Oceanography Terms
Porphyrins: Consist of four nitrogen- containing pyrrole rings linked by methane groups
to form a resonating ring system. This ring system can stabilize a central metal
ion. Important in the biochemistry of living systems. Account for less than 1% of
the DOC in the water column because of their extremely low solubilities.
Proteins: Polymeric amino acids linked by amide bonds.
Purines: A type of nucleotide. Adenine and guanine are the purines.
Pyridines: Same as purines, but pyridine base instead of purine. Cytosine, thymine, and
uracil are the pyridines.
Saturated Hydrocarbons: Hydrocarbons with no double or triple bonds. Saturated hydrocarbons are primarily isoprenoids, normal paraffins, and steranes.
Steroids: Closely related structurally and biochemically to terpenes. All have the same
basic carbon skeleton and are unique in the position of double bonds and functional groups. Cholesterol is the most abundant animal sterol, while ergosterol is
the principal plant sterol.
Terpenoids: Natural products built of five- carbon atom isoprene units. Most are biosynthesized by plants. Characterized by a wide variety of oxygen- containing
functional groups; may either be found as oxygen- deficient hydrocarbons or as
oxygen- containing esters, aldehydes, ketones, alcohols, carboxylic acids, etc.
Wax Esters: Formed by the reaction of a carboxylic acid with an alcohol. They are simple
esters of long- chain fatty alcohols with long- chain fatty acids. They are important
cell wall components of many higher plants and comprise a significant fraction of
soil lipids.
X.
Processes in the Oceans
Photochemical Processes
Absorption: The loss of energy from radiation by the medium through which the radiation is passing.
Chromophore: An atom or molecule that can absorb light.
Competitive Reactions: When two or more reactions may take place at the same time.
Dark Reaction: A reaction that occurs in the dark to reverse the reaction that takes place
in the presence of light.
Electromagnetic Radiation: Electromagnetic waves and, especially, the associated electromagnetic energy (i.e., the energy associated with electric or magnetic fields).
Emission: The loss of radiation of energy by means of electromagnetic waves.
Excitation: The process in which an atom or molecule gains energy from electromagnetic
radiation or by collision, raising it to an excited state.
Excited State: When the light energy absorbed by an atom or molecule raises the electrons
to a higher rotational or vibrational energy state.
Fluorescence: The emission of electromagnetic radiation from an excited molecule from a
singlet state to the ground state.
Grotthus–Draper Law: Only light that is absorbed can cause a photochemical effect.
Ground State: The stationary state of lowest energy of an atom or molecule.
Hydrogen Peroxide (H 2 O 2 ): Unstable, colorless, heavy liquid. Soluble in water and alcohol. Used as a bleach.
Glossary of Chemical Oceanography Terms
Porphyrins: Consist of four nitrogen- containing pyrrole rings linked by methane groups
to form a resonating ring system. This ring system can stabilize a central metal
ion. Important in the biochemistry of living systems. Account for less than 1% of
the DOC in the water column because of their extremely low solubilities.
Proteins: Polymeric amino acids linked by amide bonds.
Purines: A type of nucleotide. Adenine and guanine are the purines.
Pyridines: Same as purines, but pyridine base instead of purine. Cytosine, thymine, and
uracil are the pyridines.
Saturated Hydrocarbons: Hydrocarbons with no double or triple bonds. Saturated hydrocarbons are primarily isoprenoids, normal paraffins, and steranes.
Steroids: Closely related structurally and biochemically to terpenes. All have the same
basic carbon skeleton and are unique in the position of double bonds and functional groups. Cholesterol is the most abundant animal sterol, while ergosterol is
the principal plant sterol.
Terpenoids: Natural products built of five- carbon atom isoprene units. Most are biosynthesized by plants. Characterized by a wide variety of oxygen- containing
functional groups; may either be found as oxygen- deficient hydrocarbons or as
oxygen- containing esters, aldehydes, ketones, alcohols, carboxylic acids, etc.
Wax Esters: Formed by the reaction of a carboxylic acid with an alcohol. They are simple
esters of long- chain fatty alcohols with long- chain fatty acids. They are important
cell wall components of many higher plants and comprise a significant fraction of
soil lipids.
X.
Processes in the Oceans
Photochemical Processes
Absorption: The loss of energy from radiation by the medium through which the radiation is passing.
Chromophore: An atom or molecule that can absorb light.
Competitive Reactions: When two or more reactions may take place at the same time.
Dark Reaction: A reaction that occurs in the dark to reverse the reaction that takes place
in the presence of light.
Electromagnetic Radiation: Electromagnetic waves and, especially, the associated electromagnetic energy (i.e., the energy associated with electric or magnetic fields).
Emission: The loss of radiation of energy by means of electromagnetic waves.
Excitation: The process in which an atom or molecule gains energy from electromagnetic
radiation or by collision, raising it to an excited state.
Excited State: When the light energy absorbed by an atom or molecule raises the electrons
to a higher rotational or vibrational energy state.
Fluorescence: The emission of electromagnetic radiation from an excited molecule from a
singlet state to the ground state.
Grotthus–Draper Law: Only light that is absorbed can cause a photochemical effect.
Ground State: The stationary state of lowest energy of an atom or molecule.
Hydrogen Peroxide (H 2 O 2 ): Unstable, colorless, heavy liquid. Soluble in water and alcohol. Used as a bleach.