When defining a medical term, one usually begins the defintion with the definition of the:

Suffix

When defining a medical term, one begin the definition with the definition of SUFFIX.

Explanation:

Suffix refers to words added to the end of words to add meaning to the words or change the word functions.

When defining a medical term, one begin the definition with the definition of SUFFIX or you define at the end because the suffix of medical terms signifies procedures, diseases, conditions which is added to prefix( word that begin) which signify the meaning of term and give anatomical location or function.

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.

answer: 45

explanationyou have to add as well to be it could be