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Copyright © 2017 Pearson Education, Inc.
CHAPTER 26
The Chemistry of the Nucleic Acids
Important Terms
anticodon
the three bases at the bottom of the middle loop in tRNA.
base
a nitrogen-containing heterocyclic compound (a purine or a pyrimidine) found in
DNA and RNA.
codon
a sequence of three bases in mRNA that specifies the amino acid to be
incorporated into a protein.
deamination
a hydrolysis reaction that results in the removal of ammonia.
deoxyribonucleic acid (DNA)
a polymer of deoxyribonucleotides containing all the genetic information of an
organism.
deoxyribonucleotide
a nucleotide where the sugar component is d-2-deoxyribose.
dinucleotide
two nucleotides linked by a phosphodiester bond.
double helix
the term used to describe the secondary structure of DNA.
exon
a stretch of bases in DNA that are a portion of a gene.
gene
a segment of DNA that encodes a protein.
gene therapy
a technique that inserts a synthetic gene into the DNA of an organism that is
defective in that gene.
genetic code
the amino acid specified by each three-base sequence of mRNA.
genetic engineering
recombinant DNA technology where DNA segments are inserted into DNA in a
host cell and allowed to replicate.
human genome
the total DNA of a human cell.
major groove
the wider and deeper of the two alternating grooves in DNA.
minor groove
the narrower and more shallow of the two alternating grooves in DNA.
nucleic acid
a chain of five-membered ring sugars linked by phosphodiester groups with each
sugar bearing a heterocyclic amine at the anomeric carbon in the
b
-position.
The two kinds of nucleic acids are DNA and RNA.
nucleoside
a heterocyclic base (purine or pyrimidine) bonded to the anomeric carbon of a
sugar (d-ribose or d-2-deoxyribose) in the
b
-position.
nucleotide
a nucleoside with one of its OH groups bonded to a phosphate group via a
phosphoester linkage.