RNA, DNA Flashcards
M RNA
Messenger RNA (mRNA) is a large family of RNA molecules that convey genetic information from DNA to the ribosome, where they specify the amino acid sequence of the protein products of gene expression
RNA
ribonucleic acid, a nucleic acid present in all living cells. Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins, although in some viruses RNA rather than DNA carries the genetic information.
R RNA
Ribosomal RNA is a basic building block for ribosomes Together with protein they make up ribosomes.
T RNA
A Transfer RNA is an adaptor molecule composed of RNA, typically 73 to 94 nucleotides in length, that serves as the physical link between the nucleotide sequence of nucleic acids and the amino acid sequence of proteins.
Uracil
a compound found in living tissue as a constituent base of RNA. In DNA its place is taken by thymine.
Ribose
A sugar of the pentose class that occurs widely in nature as a constituent of nucleosides and several vitamins and enzymes.
Replication
the action of copying or reproducing something.
Replication fork
a Y-shaped part of a chromosome that is the site for DNA strand separation and then duplication
Helicase
Helicases are a class of enzymes vital to all living organisms. Their main function is to unpackage an organism’s genes.
Polymerase
an enzyme that brings about the formation of a particular polymer, esp. DNA or RNA.
Protein Synthesis
The creation of proteins by cells that uses DNA, RNA and various enzymes.
Codon
a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule.
Translation
A step in protein biosynthesis wherein the genetic code carried by mRNA is decoded to produce the specific sequence of amino acids in a polypeptide chain. The process follows transcription in which the DNA sequence is copied (or transcribed) into an mRNA.
Transcription
Transcription is the first step of gene expression, in which a particular segment of DNA is copied into RNA by the enzyme RNA polymerase. Both RNA and DNA are nucleic acids, which use base pairs of nucleotides as a complementary language that can be converted back and forth from DNA to RNA by the action of the correct enzymes. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. As opposed to DNA replication, transcription results in an RNA complement that includes the nucleotide uracil (U) in all instances where thymine (T) would have occurred in a DNA complement. Also unlike DNA replication where DNA is synthesized, transcription does not involve an RNA primer to initiate RNA synthesis.Although Transcription is nice.
Promoter
A site in a DNA molecule at which RNA polymerase and transcription factors bind to initiate transcription of mRNA.
Termination signal
A termination signal is found at the end of the part of the chromosome being transcribed during transcription of mRNA. It is needed because only parts of the chromosome are transcribed. The beginning part is started at the promoter and then ended at the termination signal.
Anticodon
a sequence of three nucleotides forming a unit of genetic code in a transfer RNA molecule, corresponding to a complementary codon in messenger RNA.
Introns
a segment of a DNA or RNA molecule that does not code for proteins and interrupts the sequence of genes.