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Alkaloids A class
of over 3,000 nitrogen-containing chemicals (such as caffeine and cocaine)
that are produced by plants but have effects in humans and animals.
Amino acids A class of 20 chemical
units that are the building blocks of peptides and proteins.
Amylase An enzyme found in saliva
that breaks down starch into simple sugars.
Anabolic A type of reaction or series
of reactions in which complex molecules are synthesized from simpler ones;
the opposite of catabolic.
Aquaculture The underwater cultivation
of animals and plants for food or for other purposes.
-ase A suffix common to many, but not
all, enzymes.
Atom The smallest particle of matter
that maintains the property of an element in the periodic table; atoms are
composed of subatomic particles called electrons, neutrons, and protons,
which themselves are composed of even tinier subatomic particles such as
quarks.
ATP Adenosine triphosphate; the energy
currency of metabolism in all organisms.
ATP synthase An enzyme in mitochondria
that produces ATP by adding a phosphate group to the molecule ADP.
Base A nitrogen-containing
building block of DNA; the two types are the purines adenine (A) and guanine
(G), and the pyrimidines thymine (T)and cytosine (C).
Bi A prefix meaning two.
Biochemistry The scientific
study of the chemistry of living cells, tissues, organs, and organisms.
Biochip An electronic device containing
organic materials.
Biopolymer In a living organism,
any large molecule (such as a protein, nucleic acid, lipid, or polysaccharide)
made from smaller parts.
Biosensor A system or device that
detects a chemical or chemicals in a biological material.
Biotechnology The industrial
use of living organisms or biological methods derived through basic research;
examples range from genetic engineering to making cheese or bread.
Bond Physical forces holding together
two atoms in a molecule.
Carbohydrate
A chemical compound made up of a chain or ring of carbon atoms to which
hydrogen and oxygen atoms are attached in a defined ratio (2:1); includes
simple sugars like glucose and complex sugars like chitin (the exoskeleton
of crabs).
Carbohydrate biology
A branch of chemistry dedicated to the study of the many types of carbohydrate
molecules.
Catabolic A type of reaction or
series of reactions in which complex molecules are broken down into simpler
ones; the opposite of anabolic.
Catalyst A substance that speeds
up a chemical or biochemical reaction that would have occurred anyway (without
help), but at a much slower rate; enzymes are biological catalysts.
Catalytic antibody An
antibody that speeds up a chemical reaction; also called "abzymes," these
antibodies use a molecule called a hapten to mimic the middle, "transition"
state of a reaction.
Chaperone Any of a class of proteins
that helps proteins fold or escorts proteins or other molecules throughout
the cell.
Chirality The ability of a chemical
substance to exist in two mirror-image forms, each of which rotates polarized
light in opposite directions.
Cholesterol A lipid unique to
animal cells that is used in the construction of cell membranes and as a
building block for some hormones.
Clinical trial A scientific
study in which physician-researchers study the effects of potential medicines
on people; usually conducted in three phases (I, II, and III) that determine
safety, whether the treatment works, and if it's better than current therapies,
respectively.
Cofactor A helper molecule (either
inorganic, such as a metal ion, or organic, such as a vitamin) required
by an enzyme.
Combinatorial chemistry
The random assembly of various chemical units into large so-called "libraries"
of new synthetic compounds.
Coprophile A feces-loving organism.
Covalent bond A force that
holds together two or more atoms, formed when electrons travel between the
atoms' nuclei (and are thus "shared").
Cyanobacteria A type of bacteria
living in damp soil or rocks, or fresh or salt water, that performs photosynthesis,
a process in which light, energy, water, and carbon dioxide are converted
into oxygen and carbohydrates (sugars).
Di- A prefix
meaning two.
DNA (deoxyribonucleic acid) A double-stranded molecule that encodes genetic information; composed of four nucleotides containing the bases adenine (A), cytosine (C), guanine (G), and thymine (T).
DNA polymerase An enzyme that copies, and sometimes repairs, DNA.
Double bond A type of covalent bond in which a pair of atoms shares two pairs of electrons.
Electrolyte A charged molecule (such as a sodium or potassium ion) that is present in body fluids.
Element A component of the periodic table; a pure substance that cannot be separated into simpler substances by chemical means.
Enantiomer One of two "mirror images" of a chiral molecule.
Endotoxin Any of a class of lipids found in the outer membranes of gram-negative bacteria; in people, the toxins cause diarrhea and/or septic shock.
Enterococci Intestinal bacteria that are often resistant to the antibiotic vancomycin.
Enzyme A molecule that acts as a catalyst, speeding up biochemical reactions.
Fluorescence The property of giving off light at a particular wavelength (emission wavelength) when illuminated by light of a different wavelength (excitation wavelength).
Forensic science The application of scientific knowledge to questions of civil and criminal law.
Genetic engineering The manipulation of an organism's genes—introducing, eliminating, or changing them—using modern molecular biology techniques.
Glycolipid A lipid covalently linked to a sugar.
Glycoprotein A protein covalently linked to a sugar.
Glycosaminoglycan A large molecule found on the surface of membrane-encased cells that consists of a network of long, branched chains of sugars and smaller, nitrogen-containing molecules.
Host-guest chemistry A branch of chemistry in which researchers study the interactions between two molecules (natural or synthetic) with the goal of either mimicking or blocking a biological effect caused by the molecules' interaction.
Hydrocarbon An organic molecule consisting of hydrogen and carbon atoms only.
-ine A suffix common to many of the amino acids.
Inflammation The body's reaction to noxious stimuli or foreign particles, resulting in swelling, redness, and pain.
Inorganic Describing a substance not derived from a living organism and/or not composed of carbon and hydrogen (a hydrocarbon).
In silico Literally "within silicon"; refers to modeling research conducted with computers only.
Ion An electrically charged atom.
Ionic bond A force that holds together two electrically charged atoms (called ions).
Lipid A fatty, waxy, or oily compound that will not dissolve in water; it contains hydrogen, carbon, and oxygen, but proportionally far less oxygen than carbohydrates.
Lipid A A key component of lipopolysaccharide.
Lipo- A prefix meaning "lipid," or fat.
Lipopolysaccharide An integral part of the outer cell membrane of certain types of bacteria (so-called gram-negative strains).
Mass spectrometry A technique used to determine the composition and abundance of the atoms in a molecular substance, starting with a very small amount of sample.
Metabolic engineering The targeted and purposeful alteration (using genetic engineering techniques) of an organism's metabolic pathways in order to better understand how the pathways work or to redesign them to produce a different set of products.
Metabolism A set of enzyme-catalyzed reactions in a living organism that builds and breaks down organic molecules, producing or consuming energy in the process.
Metabolite A chemical intermediate in metabolic reactions.
Model organism A bacterium, animal, or plant used by scientists to study basic research questions; common model organisms include yeast, flies, worms, frogs, and fish.
Nano- A prefix meaning one-billionth.
Nanotechnology A branch of science and engineering devoted to the design and production of extremely small electronic devices and circuits built from individual atoms and molecules.
Neoglycopolymer A glycoprotein mimic; a synthetic molecule consisting of polymers with carbohydrates attached.
Nuclear magnetic resonance spectroscopy A technique used to study the physical, chemical, and biological properties of matter; in this method, scientists subject a molecule to a strong magnet and watch what happens to the atoms that make up the molecule, which provides information about the molecule's composition.
Nucleic acid A large molecule composed of units of nucleotides; includes both RNA and DNA.
Nucleotide A subunit of RNA or DNA containing a base, a phosphate, and a sugar; thousands of nucleotides link up to form a molecule of DNA or RNA.
Olefin metathesis A chemical reaction in which all of the double bonds in a hydrocarbon molecule are broken and then rearranged.
Oligosaccharide A molecule made up of several simple sugars linked together.
Organic chemistry A branch of chemistry dedicated to the study of the structures, synthesis, and reactions of carbon-containing compounds.
Organophosphate A class of toxic organic molecules containing phosphate, and often fluoride, that are used as insecticides and nerve gases (such as sarin); many of these molecules block the action of an enzyme (acetylcholinesterase) that recycles an important brain chemical called acetylcholine.
-ose A suffix common to many carbohydrates.
Oxo-or oxy- Prefixes meaning oxygen-containing.
Peptide A molecule consisting of a chain of amino acids; a small protein fragment.
Peptide bond The chemical link joining amino acids in peptides and proteins.
Peptidomimetic A chemical compound that mimics the ability of a peptide to recognize certain physiological molecules, such as proteins and DNA.
Pharmacogenetics The study of how people's genetic make-up affects their response to medicines.
Phenylketonuria A genetic disorder in which the body cannot break down the amino acid phenylalanine; abbreviated PKU.
Phosphate group A chemical unit consisting of an atom of phosphate bound to four oxygen atoms; often attached to other biological molecules, such as proteins, sugars, and lipids.
Phospho- A prefix meaning phosphate-containing.
Phospholipid A lipid made up of glycerol and fatty acids, with a phosphate group attached.
Phosphotriesterase A bacterially produced enzyme that breaks down organophosphates like sarin.
Physiology The study of how living organisms function.
Plasma membrane The membrane that separates the contents of a cell from its outside environment; it consists of a double layer of phospholipids with embedded proteins.
Polymer A large molecule formed by combining many similar, smaller molecules.
Polysaccharide Any of a class of carbohydrates consisting of chains of simple sugars.
Product A substance formed as the result of a chemical reaction.
Protecting group A removable chemical unit used by synthetic chemists to purposefully cover up certain regions of a molecule so they do not react with other compounds during a reaction.
Protein A large molecule composed of one or more chains of amino acids in a specific order and folded shape determined by the sequence of nucleotides in the gene encoding the protein.
Protein synthesis The process in which the genetic code carried by messenger RNA directs cellular organelles called ribosomes to produce proteins from amino acids.
Reaction rate A measure of how fast a chemical reaction occurs.
Ribonucleotide reductase The enzyme in all organisms that catalyzes the conversion of nucleosides to deoxynucleosides.
RNA (ribonucleic acid) A chemical found in cells that serves as an intermediate in the synthesis of proteins.
Structural biology A branch of biology dedicated to the study of the three-dimensional structures of proteins and other molecules to help understand the function of these molecules in the cell.
Substrate A molecule acted upon by an enzyme.
Suicide substrate An enzyme substrate that itself is not toxic but that produces a toxic metabolic product.
Superoxide dismutase A copper-and zinc-containing enzyme present in all oxygen-using organisms that scavenges free radicals and converts them into hydrogen peroxide and oxygen.
Synthetic chemistry A branch of chemistry in which chemists devise ways to make specific compounds of interest and/or develop new chemical reactions for this purpose.
Transition state The activated form of a molecule that has partly undergone a chemical reaction.
van der Waals force A weak physical force that holds together two molecules or two different parts of the same molecule.