Final answer:
In nucleic acids like DNA and RNA, phosphate groups are typically attached to the 5' carbon of the sugar molecule, either deoxyribose in DNA or ribose in RNA, forming the sugar-phosphate backbone.
Step-by-step explanation:
Phosphate groups in the body's biomolecules, specifically nucleotides, are typically attached to the sugar component of the nucleic acids DNA and RNA. In DNA and RNA structures, the phosphate group is connected to the 5' carbon of the sugar molecule deoxyribose in DNA and ribose in RNA. The attachment of the phosphate group to the 5' carbon establishes the sugar-phosphate backbone of the nucleic acid strands, which is vital for the structural integrity of DNA and RNA.
The carbon atoms of the sugar molecule in nucleotides are numbered as follows: 1', 2', 3', 4', and 5' (1' is read as "one prime"). The phosphate group attachment forms a 5'-3' phosphodiester linkage between the sugars of adjacent nucleotides when nucleic acids are formed. This linkage is crucial for the polymerization of nucleic acids, generating a directional chain that extends from the 5' to 3' end.