The Genetic Code and Transcription

These flashcards cover key concepts related to the genetic code and transcription as presented in Dr. Cindy Malone's lecture.

What does the central dogma of molecular genetics describe?

The directional flow of genetic information from DNA to RNA to protein.

What is a codon?

A triplet of ribonucleotides that specifies an amino acid.

What does it mean that the genetic code is unambiguous?

Each triplet specifies only one amino acid.

How is the genetic code described as degenerate?

A given amino acid can be specified by more than one triplet codon.

What are the roles of the start and stop codons in genetic translation?

Start codons initiate translation, while stop codons terminate translation.

What is a frameshift mutation?

A change in the reading frame of a gene due to insertions or deletions in the nucleotide sequence.

Describe the nonoverlapping nature of the genetic code.

The genetic code reads three nucleotides at a time in a continuous, linear manner without overlapping.

What is the triplet binding assay used for?

To determine specific codon assignments by binding ribosomes to single codons and amino acid-charged tRNA.

What amino acid is encoded by the start codon AUG?

Methionine.

What are termination codons and what do they signify?

Termination codons (UAG, UAA, UGA) do not code for any amino acids and signal the end of translation.

What effect do nonsense mutations have on protein synthesis?

They produce a stop codon internally in a gene, leading to premature termination of translation.

What is the role of mRNA in protein synthesis?

mRNA serves as the intermediate that carries genetic information from DNA to the ribosomes for protein synthesis.

List one feature of the genetic code.

The genetic code is nearly universal, used by viruses, prokaryotes, archaea, and eukaryotes.