nucleic acid Flashcards
An individual gets the information from its parents through
_____, the transfer of characteristics, anatomical or
biochemical, from generation to generation
heredity
Biologists suspected that the transmission of hereditary
information took place in the ____, more specifically in
structures called _____
nucleus. chromosomes.
Chemical analysis of nuclei showed chromosomes are made
up largely of proteins called ________
histones and nucleic acids.
- Are informational molecules made up of
polymers of nucleotides linked together
by phosphodiester bonds.
NUCLEIC ACIDS
-They act as repositories and
transmitters of genetic information
NUCLEIC ACIDS
Both RNA and DNA are polymers built from monomers
called
nucleotides.
A nucleotide is composed of:
a base (nitrogenous or amine bases)
a monosaccharide (pentose sugar)
and a phosphate group
Are heterocyclic ring compounds which consist of
nitrogen in addition to carbon and hydrogen.
AMINE BASES
D-ribose is found in _ nucleotides,
RNA
while 2’-deoxy-D-ribose is found in ___ nucleotides.
DNA
The _______are
numbered to facilitate identification and naming of
many derivative compounds.
pentose sugar and the nitrogenous bases
a nucleic acid constituent
consisting of a sugar residue bonded to a
heterocyclic purine or pyrimidine base
NUCLEOSIDE –
a nucleic acid constituent
consisting of a sugar residue bonded to
both a heterocyclic purine or pyrimidine
base and to a phosphate group
NUCLEOTIDE –
serves regulatory functions outside
the cell, such as in glycogen metabolism.
regulates the break down of glycogen.
Cyclic AMP (cAMP)
2 important features of all polynucleotide
. A polynucleotide has a sense of
directionality
DNA structure
b. A polynucleotide has individuality,
determined by the sequence of its
bases (the nucleotide sequence)
– small proteins that participate
in forming the nucleosomal structure of
the chromatin
HISTONES
– the total genetic information contained in a cell,
an organism or virus.
Genome
MRNA contains a sequence of three bases specifying for
an amino acid. This sequence is called a ___
codon.
: Formed directly by
DNA transcription and converted to mRNA at posttranscription processing
Heterogeneous nuclear RNA (hnRNA)
Facilitates the conversion of hnRNA to
mRNA.
Small nuclear RNA
– the transfer of
information to DNA for its conservation
from cell to cell
REPLICATION
A section of DNA that, when
transcribed, codes for a protein or RNA.
Known as the coding sequences,
short for “expressed sequences”.
Exon:
A section of DNA that does not code
for anything functional.
Known as the noncoding sequences,
short for “intervening sequences”.
Intron:
Enzymes called __ catalyze
transcription
polymerases (poly)
poly I for - formation, poly II for
- formation, and poly III for - formation
rRNA mRNA tRNA
A eukaryotic gene has
two parts:
A structural gene
regulatory gene
A ____ that
is transcribed into
RNA; the structural
gene is made of
exons and introns.
structural gene
A _____
that controls
transcription; it is not
transcribed but has
control elements, one
of which is the
promoter.
regulatory gene
Termination takes place when any of the stop codons are
encountered: _______The release factors are
involved, and the ribosomes dissociate into the large and small
subunits, releasing the polypeptide chain and mRNA.
UAG, UGA and UAA.
An error in the copying of a sequence of bases.
Mutation:
– structural isomers that differ
in the location of their hydrogens and
double bonds
Tautomers
: a chemical or physical agents
that causes a base change or mutation
in DNA.
Mutagen
