AP BIOLOGY

THE MOLECULAR BASIS OF INHERITANCE

STRUCTURE OF NUCLEIC ACIDS

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which of the following is NOT a component of a DNA nucleotide?
A
phosphate
B
nitrogen base
C
deoxyribose sugar
D
ribose sugar
Explanation: 

Detailed explanation-1: -Ribose sugar is not a component of DNA. RNA constitutes ribose sugar which is a carbon sugar and is a monosaccharide. DNA consists of deoxyribose sugar which is linked to a nitrogenous base at the first carbon through a glycosidic bond. It is a pentose sugar.

Detailed explanation-2: -Nucleotides that make the DNA strands contain deoxyribose sugar, phospate molecule and one nitrogenous base out of adenine, guanine, thymine and cytosine. Uracil is never a part of nucleotide of DNA.

Detailed explanation-3: -A nucleotide consists of a sugar molecule (either ribose in RNA or deoxyribose in DNA) attached to a phosphate group and a nitrogen-containing base. The bases used in DNA are adenine (A), cytosine (C), guanine (G) and thymine (T).

Detailed explanation-4: -DNA is made up of four building blocks called nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C). The nucleotides attach to each other (A with T, and G with C) to form chemical bonds called base pairs, which connect the two DNA strands.

There is 1 question to complete.