Look at the structure below.
Structure X includes a deoxyribose sugar, a phosphate group, and a nitrogenous base. What is this structure called?
a
nucleotide
b
hydrogen bond
c
sugar-phosphate backbone
d
complementary base pair
The structure described in the question consists of a deoxyribose sugar, a phosphate group, and a nitrogenous base. This structure is called a nucleotide.
To arrive at this answer, let's break down the options and see which one fits the description.
a) Nucleotide - The description matches the components of a nucleotide, which consists of a sugar (in this case, deoxyribose), a phosphate group, and a nitrogenous base. Therefore, option "a" is a potential answer.
b) Hydrogen bond - A hydrogen bond is a type of chemical bond that forms between the nitrogenous bases in the DNA double helix structure, but it does not specifically describe the structure mentioned in the question. Thus, option "b" can be eliminated.
c) Sugar-phosphate backbone - The sugar-phosphate backbone refers to the repeating pattern of sugar molecules and phosphate groups that make up the outer edges or sides of the DNA double helix. It does not include the nitrogenous bases. Therefore, option "c" does not match the description provided.
d) Complementary base pair - Complementary base pairs refer to the specific pairing between the nitrogenous bases in DNA. While they are important for DNA structure and replication, they do not capture the complete structure described in the question. Hence, option "d" can be dismissed.
Considering this analysis, the correct answer is indeed option "a" - nucleotide.