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 element(s) are found in nucleic acids?
A
carbon/hydrogen
B
oxygen
C
phosphorus
D
nitrogen
E
sulfur
Explanation: 

Detailed explanation-1: -Nucleic acids contain the same elements as proteins: carbon, hydrogen, oxygen, nitrogen; plus phosphorous (C, H, O, N, and P). Nucleic acids are very large macromolecules composed of repetitive units of the same building blocks, nucleotides, similar to a pearl necklace made of many pearls.

Detailed explanation-2: -The five-carbon sugar ring and the content of the nitrogenous base between DNA and RNA are slightly different from each other. Four different types of nitrogenous bases are found in DNA: adenine (A), thymine (T), cytosine (C), and guanine (G). In RNA, the thymine is replaced by uracil (U).

Detailed explanation-3: -In the 1920’s nucleic acids were found to be major components of chromosomes, small gene-carrying bodies in the nuclei of complex cells. Elemental analysis of nucleic acids showed the presence of phosphorus, in addition to the usual C, H, N & O. Unlike proteins, nucleic acids contained no sulfur.

Detailed explanation-4: -Nitrogen is in all amino acids and nucleotides, and therefore in all proteins and nucleic acids.

There is 1 question to complete.