# Covalent Bond --- A **covalent bond** is a [[chemical bond]] between two [[element#Nonmetals|nonmetals]] where two atoms are connected to each other because they share one or more [[atom|electrons]]. Depending on how many electrons are shared this can be a single, double, or even triple bond. ## Polar Bonds Electrons are not necessarily shared evenly between the two bonded atoms, in which case they are [[polar and nonpolar|polar]]. This happens because electrons spend more of their time near the atom with the higher [[electronegativity]], which gives that end of the molecule a slightly negative charge. ## Special Covalent Bonds A **peptide bond** is a type of covalent bond that is formed between [[amino acids]] in a protein chain. These bonds are made through a [[hydrolysis and condensation reactions|condensation reaction]]. ![[peptide bond.png]] A **glycosidic bond** is a [[covalent bond]] that occurs between two [[monosaccharide|sugar]] molecules. It is formed from a [[hydrolysis and condensation reactions|dehydration reaction]] between the two [[functional group|hydroxyl]] groups. The process of forming a glycosidic bond is called "glycosylation". Breaking down the glycosidic bonds between polysaccharides and disaccharides is what drives [[metabolism]], which does whatever it can to get that [[glucose]]. ___