Federal Home Loan Mortgage Corporation: FRM: fixed-rate mortgage: GAAP: generally accepted accounting principles: GSE: government-sponsored enterprise: HCLTV: home equity combined loan-to-value: HELOC: home equity line of credit: HFA: Housing Finance Agency: HOA: homeownersâ association: HOEPA: Home Ownership and Equity Protection Act of 1994
Hydrogen bonds, as well as the other types of noncovalent interactions, are very important in terms of the binding of a ligand to a protein. In section 1.3, we saw a 'space-filling' picture of an enzyme with its substrate bound in its active site.
NaCl (common salt) is an example of an ionic substance. Covalent bonding occurs when atoms share electrons with each other. This gives rise to two types of structures: molecules and covalent network solids. Methane (CH4) is a covalent molecule and glass is a covalent network solid. In molecules we can distinguish individual covalent bonds between pairs of atoms.