Flashcard terms chp 14

Gene Expression

The process by which genetic information in a gene is used to produce a functional product, typically a protein.

Transcription

The synthesis of RNA from a DNA template, where RNA polymerase links RNA nucleotides complementary to the DNA template strand.

Messenger RNA (mRNA)

The RNA molecule that carries genetic information from DNA to the ribosome, specifying the amino acid sequence of the protein.

Translation

The process where the sequence of an mRNA is decoded to produce a polypeptide, which folds into a functional protein.

Ribosomes

Cellular structures where translation occurs, facilitating the binding of tRNA and mRNA to synthesize proteins.

Primary Transcript

The initial RNA transcript synthesized from the DNA template, which undergoes processing to become mRNA.

Triplet Code

The genetic code where three nucleotide bases (codon) in mRNA specify an amino acid.

Template Strand

The DNA strand that serves as the template for RNA synthesis during transcription.

Codons

Triplets of nucleotides in mRNA that specify particular amino acids or stop signals during translation.

Reading Frame

The way nucleotides in mRNA are grouped into codons for translation, starting from a specific nucleotide.

RNA Polymerase

The enzyme that synthesizes RNA by linking RNA nucleotides complementary to the DNA template.

Promoter

A DNA sequence where RNA polymerase binds to initiate transcription.

Terminator

A DNA sequence that signals the end of transcription.

Transcription Unit

The stretch of DNA transcribed into an RNA molecule.

Start Point

The nucleotide where RNA polymerase begins RNA synthesis.

Transcription Factors

Proteins that help RNA polymerase bind to the promoter and initiate transcription.

Transfer RNA (tRNA)

RNA molecules that carry amino acids to the ribosome and match them to the coded mRNA message.

Ribosomal RNA (rRNA)

RNA molecules that form the core of ribosome’s structure and catalyze protein synthesis.

Mutation

A change in the nucleotide sequence of DNA.

Point Mutation

A mutation affecting a single nucleotide pair.

Nucleotide Pair Substitution

Replacement of one nucleotide pair with another.

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.

Nonsense Mutation

A mutation that creates a stop codon, leading to a truncated protein.

Insertion

Addition of one or more nucleotide pairs in a gene.

Deletion

Loss of one or more nucleotide pairs in a gene.

Frameshift Mutation

Insertions or deletions that alter the reading frame of the gene.

Mutagen

An agent that causes mutations.