covalent bond

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bond

 [bond]
the linkage between atoms or radicals of a chemical compound, or the symbol representing this linkage and indicating the number and attachment of the valencies of an atom in constitutional formulas, represented by a pair of dots or a line between atoms, e.g., H—O—H, H—C≡C—H or H:O:H, H:C:::C:H.
coordinate covalent bond a covalent bond in which one of the bonded atoms furnishes both of the shared electrons.
covalent bond a chemical bond between two atoms or radicals formed by the sharing of a pair (single bond), two pairs (double bond), or three pairs of electrons (triple bond).
disulfide bond a strong covalent bond, —S—S—, important in linking polypeptide chains in proteins, the linkage arising as a result of the oxidation of the sulfhydryl (SH) groups of two molecules of cysteine.
high-energy phosphate bond an energy-rich phosphate linkage present in adenosine triphosphate (ATP), phosphocreatine, and certain other biological molecules. On hydrolysis at pH 7 it yields about 8000 calories per mole, in contrast to the 3000 calories yielded by phosphate esters. The bond stores energy that is used to drive biochemical processes, such as the synthesis of macromolecules, contraction of muscles, and the production of the electrical potentials for nerve conduction.
high-energy sulfur bond an energy-rich sulfur linkage, the most important of which occurs in the acetyl-CoA molecule, the main source of energy in fatty acid biosynthesis.
hydrogen bond a weak, primarily electrostatic, bond between a hydrogen atom bound to a highly electronegative element (such as oxygen or nitrogen) in a given molecule, or part of a molecule, and a second highly electronegative atom in another molecule or in a different part of the same molecule.
ionic bond a chemical bond in which electrons are transferred from one atom to another so that one bears a positive and the other a negative charge, the attraction between these opposite charges forming the bond.
peptide bond the —CO—NH— linkage formed between the carboxyl group of one amino acid and the amino group of another; it is an amide linkage joining amino acids to form peptides.

covalent bond

a chemical bond that forms by the sharing of two electrons between atoms. A double bond is formed when four electrons are shared between two atoms; a triple bond is formed when six electrons are shared between two atoms.

covalent bond (kō·vāˑ·lnt bnd),

n chemical bond that involves sharing of electrons between atoms of the same element to give a molecule of that element (e.g., nitrogen) or atoms of two or more elements to give a molecule of a compound (e.g., carbon dioxide); the predominant type of bonding in organic chemistry.

bond

the linkage between atoms or radicals of a chemical compound, or the symbol representing this linkage and indicating the number and attachment of the valencies of an atom in constitutional formulas, e.g. H−O−H, H−C= C−H and can be represented by a pair of dots between atoms, e.g. H:O:H, H:C:::C:H.

coordinate covalent bond
a covalent bond in which one of the bonded atoms furnishes both of the shared electrons.
covalent bond
a chemical bond between two atoms or radicals formed by the sharing of a pair (single bond), two pairs (double bond) or three pairs of electrons (triple bond).
disulfide bond
a strong covalent bond, −S−S−, important in linking polypeptide chains in proteins, the linkage arising as a result of the oxidation of the sulfhydryl (SH) groups of two molecules of cysteine.
high-energy phosphate bond
an energy-rich phosphate linkage present in adenosine triphosphate (ATP), phosphocreatine and certain other biological molecules. On hydrolysis at pH 7 it yields about 8000 calories per mole, in contrast to the 3000 calories yielded by phosphate esters. The bond stores energy that is used to drive biochemical processes, such as the synthesis of macromolecules, contraction of muscles, and the production of the electrical potentials for nerve conduction.
high-energy sulfur bond
an energy-rich sulfur linkage, the most important of which occurs in the acetyl-CoA molecule, the main source of energy in fatty acid biosynthesis.
human-animal bond
the psychological interdependence between humans and companion animals.
hydrogen bond
a weak, primarily electrostatic, bond between a hydrogen atom bound to a highly electronegative element (such as oxygen or nitrogen) in a given molecule, or part of a molecule, and a second highly electronegative atom in another molecule or in a different part of the same molecule.
ionic bond
a chemical bond in which electrons are transferred from one atom to another so that one bears a positive and the other a negative charge, the attraction between these opposite charges forming the bond.
peptide bond
the −CO−NH− linkage formed between the carboxyl group of one amino acid and the amino group of another; it is an amide linkage joining amino acids to form peptides.
phosphoanhydride bond
a high energy bond present in ATP.
phosphodiester bond
links between nucleotides in nucleic acids.