A spiral shape constituting one form of the secondary structure of proteins, arising from a specific hydrogen-bonding structure.
An organic molecule possessing both carboxyl and amino groups. monomers of proteins.
An arrangement found In DNA, where two sugar-phosphate backbones run in opposite 5' - 3' directions from each other. Bk
beta (b) pleated sheet
One form of the secondary structure of proteins in which the polypeptide chain folds back and forth, or where two regions of the chain lie parallel to each other and are held together by hydrogen bonds.
A chemical agent that changes the rate of a reaction without being consumed by the reaction.
A structural polysaccharide of cell walls, consisting of glucose monomers joined by b-1, 4-glycosidic linkages.
Protein molecules that assist the proper folding of other proteins.
A structural polysaccharide of an amino sugar found in many fungi and in the exoskeletons of all arthropods.
A steroid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steroids.
A glycoprotein in the extracellular matrix of animal cells that forms strong fibers, found extensively in connective tissue and bone; the most abundant protein in the animal kingdom.
A reaction in which two molecules become covalently bonded to each other through the loss of a small molecule, usually water; also called dehydration reaction.
A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.
For proteins, a process in which a protein unravels and loses its native conformation, thereby becoming biologically inactive. For DNA, the separation of the two strands of the double helix. occurs under extreme conditions of pH, salt concentration, and temperature.
deoxyribonucleic acid (DNA)
A double-stranded, helical nucleic acid molecule capable of replicating and determining the inherited structure of a cell's proteins.
The sugar component of DNA, having one less hydroxyl group than ribose, the sugar component of RNA.
A double sugar, consisting of two monosaccharides joined by dehydration synthesis.
Strong covalent bonds formed when the sulfur of one cysteine monomer bonds to the sulfur of another cysteine monomer.
The form of native DNA, referring to its two adjacent polynucleotide strands wound into a spiral shape.
A protein serving as a catalyst, a chemical agent that changes the rate of a reaction without being consumed by the reaction.
Large molecules, not polymers, Assembled from glycerol and fatty acids, by dehydration reactions. Also called triacylglycerol. Bk
A long carbon chain carboxylic acid. vary in length, & number and location of double bonds; three ___ linked to a glycerol molecule form fat.
An amino acid that functions as a CNS neurotransmitter.
An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch.
A covalent bond formed between two monosaccharides by a dehydration reaction.
An iron-containing protein in red blood cells that reversibly binds oxygen.
A type of weak chemical bond formed when the slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule.
A chemical process that lyses, or splits, molecules by the addition of water; an essential process in digestion.
A type of weak chemical bond formed when molecules that do not mix with water coalesce to exclude the water.
One of a family of compounds, including fats, phospholipids, and steroids, that are insoluble in water.
A giant molecule formed by the joining of smaller molecules, usually by a condensation reaction. Polysaccharides, proteins, and nucleic acids are macromolecules.
A polymer consisting of many nucleotide monomers; serves as a blueprint for proteins.There are two types.
An organic molecule consisting of a nitrogenous base joined to a five-carbon sugar.
The building block of a nucleic acid, consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group.
The covalent bond between two amino acid units, formed by a dehydration reaction.
A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail.
A polymer consisting of many nucleotide monomers; serves as a blueprint for proteins. There are two types.
A polymer of many amino acids linked together by peptide bonds.
A polymer of up to over a thousand monosaccharides, formed by dehydration reactions.
The level of protein structure referring to the specific sequence of amino acids.
A three-dimensional biological polymer constructed from a set of 20 different monomers called amino acids.
One of two families of nitrogenous bases found in nucleotides. Adenine (A) and guanine (G) are ___..
One of two families of nitrogenous bases found in nucleotides. Cytosine (C), thymine (T), and uracil (U) are ___.
The particular shape of a complex, aggregate protein, defined by the characteristic three-dimensional arrangement of its constituent subunits, each a polypeptide.
ribonucleic acid (RNA)
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.
The sugar component of RNA.
saturated fatty acid
A fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds, thus maximizing the number of hydrogen atoms that can attach to the carbon skeleton.
The localized, repetitive coiling or folding of the polypeptide backbone of a protein due to hydrogen bond formation between peptide linkages.
A storage polysaccharide in plants consisting entirely of glucose.
A type of lipid characterized by a carbon skeleton consisting of four rings with various functional groups attached.
Irregular contortions of a protein molecule due to interactions of side chains involved in hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges.
Three fatty acids linked to one glycerol molecule.
unsaturated fatty acid
A fatty acid possessing one or more double bonds between the carbons in the hydrocarbon tail which reduces the number of hydrogen atoms attached to the carbon skeleton.
A technique that depends on the diffraction of an ___ beam by the individual atoms of a molecule to study the three-dimensional structure of a molecule.