CHapter 17 - Gene Espression Flashcards
Gene Expression
The process by which DNA directs the synthesis of proteins or RNA’s
What are the stages of gene expression?
Transcription and translation
Transcription
The synthesis (production) of RNA using information in DNA.
messenger rRNA (mRNA)
Carries genetic messages from the DNA to the ribosomes of a cell
Translation
The synthesis of a polypeptide using the information in mRNA. The cell must translate the nucleotide sequence of mRNA into the amino acid sequences of a polypeptide
Completes that facilitate the orderly linking of amino acids into polypeptide chains.
Ribosomes
Do prokaryotes differ from eukaryotes in transcription and translation in the flow of genetic information?
They do. Prokaryotes do not have a nucleus, so transcription and translation are not compartmentalized as they are in eukaryotes. DNA, RNA and ribosomes share the same space. This means that transcription and translation can occur simultaneously in prokaryotes. In eukaryotes, transcription occurs in the nucleus. Translation occurs in the cytoplasm.
mRNA which has not been fully processed for shipment out of the nucleus
pre-mRNA
primary transcript
The initial RNA transcript of any gene before it is processed for shipment out of the nucleus
A triple of nucleotides
Codon
The strand of DNA which provides the pattern for nucleotide synthesis
Template strand
The DNA strand which is not used as a pattern for nucleotide synthesis.
Coding strand
What is usually the starting codon for protein synthesis
AUG
Where is messenger RNA synthesized?
The template strand of a gene.
Enzyme which separates strands of DNA and joins together complementary nucleotides on the RNA strand
RNA polymerase
