Quick recap of translation basics and transformation, conjugation and transduction

BIOL 116

Transfer RNA (tRNA)

Molecule that carries amino acids to ribosomes.

Cloverleaf structure

Secondary structure of tRNA formed by intrachain bonds.

Anticodon

Three-nucleotide sequence on tRNA complementary to mRNA codon.

Messenger RNA (mRNA)

Single-stranded RNA that carries genetic information.

Phosphate-ribose backbone

Structural framework of RNA consisting of alternating phosphate and ribose.

Uracil

Nitrogen base in RNA replacing thymine found in DNA.

Ribosomes

Cellular structures that synthesize proteins from mRNA.

Polypeptide

Chain of amino acids formed during translation.

E site

Exit site on ribosome where tRNA leaves.

P site

Peptidyl site on ribosome where tRNA holds growing polypeptide.

A site

Aminoacyl site on ribosome where new tRNA binds.

Start codon

AUG, signals beginning of translation process.

Stop codons

UAA, UAG, UGA, signal termination of translation.

Codon redundancy

Multiple codons can code for the same amino acid.

Prokaryotic translation

Occurs simultaneously with transcription, no introns present.

Exons

Coding regions of DNA that are expressed as proteins.

Introns

Non-coding regions of DNA that are spliced out.

Lariat structure

Loop formed during splicing of introns from RNA.

Operon

A cluster of genes regulated together for a function.

Operon Off

Transcription suppression prevents unnecessary enzyme synthesis.

Operon On

Substrate induces transcription by releasing repressor from promoter.

Mutations

Heritable changes in DNA sequence of an organism.

Transformation

Uptake of DNA from the environment by a cell.

Conjugation

Direct transfer of DNA between bacteria via pilus.

Transduction

DNA transfer between bacteria via bacteriophages.