Question

(01.02 mc)
which of the following best compares the structure of carbohydrates and nucleic acids?
○ a carbohydrates consist of monomers of carbon, hydrogen, and oxygen, while nucleic acids consist of monomers of a sugar, a phosphate group, and a nitrogenous base.
○ b carbohydrates have four rings containing carbon, hydrogen, and oxygen, while nucleic acids have subunits containing an amino acid and a phosphate group.
○ c carbohydrates contain carbon, hydrogen, and oxygen and have a hydrophobic end and a hydrophilic end, while nucleic acids contain a carbon backbone, a side change, and an amino group.
○ d carbohydrates are made up carbon, hydrogen, and oxygen but have no repeating units, while nucleic acids have repeating units of phospholipids, carbon, and an amino group.

Explanation:

Carbohydrates are made of monomers (monosaccharides) composed of carbon, hydrogen, and oxygen. Nucleic acids (like DNA and RNA) are made of nucleotides, which are monomers consisting of a sugar (ribose or deoxyribose), a phosphate group, and a nitrogenous base. Option b is wrong as steroids (a type of lipid) have four - ring structures, not carbohydrates. Option c is incorrect because the description of having a hydrophobic and hydrophilic end is for phospholipids (lipids), and the description of carbon backbone, side chain, and amino group is for amino acids (proteins). Option d is wrong as carbohydrates have repeating units (e.g., polysaccharides are made of monosaccharide repeats), and nucleic acids' repeating units are nucleotides (not phospholipids, carbon, and amino group).

Answer:

A. Carbohydrates consist of monomers of carbon, hydrogen, and oxygen, while nucleic acids consist of monomers of a sugar, a phosphate group, and a nitrogenous base.