Transcription, Translation, and Mutations

These flashcards cover key concepts related to transcription, translation, operons, and mutations as discussed in the provided lecture notes.

Transcription

The process of converting DNA to RNA using RNA polymerase.

RNA polymerase

The enzyme responsible for synthesizing RNA from a DNA template.

Codon

A sequence of three nucleotides in mRNA that codes for a specific amino acid.

Start codon

The codon (AUG) that signals the start of translation.

Stop codon

A codon that signals the termination of translation.

Operon

A cluster of genes under the control of a single promoter, found in prokaryotic cells.

Lac operon

An example of an operon responsible for lactose metabolism in bacteria.

Tryptophan operon

An operon involved in the biosynthesis of the amino acid tryptophan.

Point mutation

A genetic mutation where a single nucleotide change results in a different codon.

Frameshift mutation

A mutation that results from the insertion or deletion of nucleotides, altering the reading frame.

Silent mutation

A mutation that does not change the amino acid sequence of a protein.

Missense mutation

A mutation that changes one amino acid in a protein sequence.

Nonsense mutation

A mutation that introduces a premature stop codon in a protein sequence.

Polycistronic mRNA

mRNA that encodes multiple proteins, characteristic of prokaryotic operons.

Ribosomal binding site (RBS)

A sequence on mRNA that is recognized by the small ribosomal subunit to initiate translation.

Peptide bond

A covalent bond that links amino acids together in a protein.

Anabolism

The metabolic process of building complex molecules from simpler ones.

Catabolism

The metabolic process of breaking down complex molecules into simpler ones.

Inducer

A molecule that initiates gene expression by disabling a repressor.

Corepressor

A small molecule that binds to a repressor and activates it, thus inhibiting gene expression.

Antiparallel

Referring to the opposite orientation of two strands of DNA or RNA.