Chapter 17 Gene Expression: From Gene To Protein Flashcards
What is Transcription
The synthesis (production) of RNA using information in the DNA.
The 2 nucleic acids are written in different forms of the same language, and the info is simply transcribed, or “rewritten,” from DNA to RNA
What is mRNA (messenger RNA)
It carries a genetic message from the DNA to the protein-synthesizing machinery of the cell (ribosomes) and specifies the primary structure of a protein.
What is Translation
The synthesis of a polypeptide using the information in the mRNA.
During this stage, there is a change in language: The cell must translate the nucleotide sequence of an mRNA molecule into the amino acid sequence of a polypeptide.
Where is the sites of translation?
Happens in the ribosomes, molecular complexes that facilitate the orderly linking of amino acids into polypeptide chains.
What is a primary transcript?
An initial RNA transcript from any gene; also called pre-mRNA when transcribed from a protein-coding gene.
What is triplet code?
A genetic information system in which a series of three-nucleotide-long words specifies a sequence of amino acids for a polypeptide chain. They are nonoverlapping
Template strand
Provides the pattern, or template, for the sequence of nucleotides in an RNA transcript.
What are codons?
A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code.
Coding strand
The nontemplate DNA strand. The sequence of the coding strand is used when a gene’s sequence is reported.
RNA polymerase
An enzyme that links ribonucleotides into a growing RNA chain during transcription, based on complementary bindings to nucleotides on a DNA template strand
