In essence, DNA is a thin and very, very long organic molecule. It is a polymer, and each of the monomers that constitute it are called

nucleotides

Explanation:

DNAs are long-chain, helical macromolecules that store genetic information They are made up of varying sequences of covalently bonded monomers called nucleotides. Four types of nucleotides make up the nucleic acid DNA, these include Adenine, Guanine, Cytosine and Thymine.

Unlike other macromolecules,  these are typically not used as an energy source and only encode protein synthesis. They comprise a 5-Carbon deoxyribose sugar, one nitrogenous base (adenine, guanine thymine, and cytosine) and a phosphate group.

Nitrogenous bases encourage base-pair formation through hydrogen bonding. Adenine forms double bonds with thymine, while cytosine forms triple bonds with guanine.

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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a. the production of carbon dioxide through the process of photosynthesis