Multiple Choice
In terms of overall electrical charge at physiological pH, what net charge does DNA typically carry and what structural feature is primarily responsible?
34
views
7. DNA and Chromosome Structure
DNA Structure
Multiple Choice
In DNA structure, what is the five-carbon (pentose) sugar found in the nucleotide backbone?
A
2-deoxyribose
B
glucose
C
ribose
D
fructose
Verified step by step guidance1
Recall that DNA (deoxyribonucleic acid) is composed of nucleotides, each containing three components: a phosphate group, a nitrogenous base, and a five-carbon sugar (pentose).
Understand that the sugar in the nucleotide backbone of DNA differs from that in RNA (ribonucleic acid). DNA contains a sugar that lacks one oxygen atom compared to RNA's sugar.
Identify the sugar in RNA as ribose, which has a hydroxyl group (-OH) attached to the 2' carbon of the sugar ring.
Recognize that the sugar in DNA is 2-deoxyribose, meaning it is ribose missing the oxygen atom on the 2' carbon (hence 'deoxy').
Conclude that among the options given, 2-deoxyribose is the correct five-carbon sugar found in the DNA nucleotide backbone.
Related Videos
Related Practice
