Transcription of two genes. (a) RNA polymerase moves from the 3â² end of the template strand, creating an RNA strand that grows in a 5â² â 3â² direction (because it must be antiparallel to the template strand).
The atoms in sugar do not form ions; instead, they share their electrons. The type of bond that forms from the sharing of electrons between the atoms of the table sugar is a covalent bond. Table sugar has a much more complex chemical structure than salt.
The sugar in DNA is 2-deoxyribose, which is a pentose (five-carbon) sugar. The sugars are joined together by phosphate groups that form phosphodiester bonds between the third and fifth carbon atoms of adjacent sugar rings. These asymmetric bonds mean a strand of DNA has a direction.