Are the individual sections of the genome that encode for a particular protein and/or effect a given action (regulation, inhibition, etc.) The section of the mRNA that gets translated into a Protein. A given (gene) sequence can (and several do) have more than one ORF, which will be used for translation depending on a set of interacting variables: age, sex, other genes, presence or absence of one or more biomolecules, stress factors (radiation, free radicals, etc.), and many others.