1.2 RNA and protein synthesis

Gene

A unique sequence of DNA nucleotides that codes for a polypeptide chain, protein, or RNA molecule.

Genome

The total number of genes in an organism.

RNA

Ribonucleic acid, made up of repeating nucleotides containing a 5-carbon sugar, phosphate group, and one of four bases (A, C, G, U).

Introns

Non-coding sequences of DNA that can be transcribed into RNA but are spliced out before translation.

Exons

Coding sequences of DNA that are translated into polypeptides/proteins.

mRNA

Messenger RNA, synthesized using DNA as a template during transcription in the nucleus, which codes for specific amino acids.

tRNA

Transfer RNA, which contains an anti-codon complementary to an mRNA codon and carries a specific amino acid.

rRNA

Ribosomal RNA, which, along with proteins, makes up ribosomes and is involved in protein synthesis.

Transcription

The process that occurs in the nucleus where mRNA is synthesized from a gene on DNA.

Translation

The process that occurs in ribosomes where a polypeptide chain is built using the sequence of codons in a mature mRNA molecule.

Codon

A sequence of three bases on mRNA that codes for a specific amino acid.

Peptide bond

A bond that links amino acids together in a polypeptide chain.

RNA splicing

The process of removing introns and joining exons to form a mature mRNA strand.

Start codon

The specific codon (AUG) that signals the beginning of protein synthesis.

Stop codon

A codon that signals the termination of protein synthesis.

Amino acids

The building blocks of polypeptides and proteins linked together by peptide bonds.