mRNA & tRNA

01mRNA & tRNA

mRNA

This section covers the structure of mRNA and its role in carrying genetic information from DNA to ribosomes.

Messenger RNA (mRNA) is a single-stranded RNA transcript formed from a gene.

Structure and role

mRNA consists of a single polynucleotide strand. Alternating ribose sugars and phosphate groups form its sugar–phosphate backbone, while the nitrogenous bases project from the strand.

Its RNA nucleotides contain adenine, cytosine, guanine and uracil, with uracil present instead of thymine.

The sequence of bases in mRNA is complementary to the DNA template strand from which it is transcribed.

mRNA carries genetic information from DNA in the nucleus to a ribosome, where its sequence is used during translation to produce a polypeptide.

The bases on mRNA are read in groups of three called codons.

AUGCACUGcodonsugar{phosphate backbonesingle-stranded mRNA with exposed bases

Create a free account to continue

Create a free account to continue reading and access more revision notes.