CENTRAL DOGMA

The flow of genetic information

from DNA to RNA to protein

Initially, the central dogma of biology was simply thought

of as

DNA mRNA protein

What do all those nitrogenous

bases mean?

On the RNA strand, each bracket contains 3 nucleotides.

3 nucleotides are called a codon, each codon represents an amino acid.

There are 64 (43) possible code words which is more than enough to code for the 20 amino acids

DNA Transcription

Transcription occurs in the nucleus of the cell.

The gene sequence is copied into messenger RNA (mRNA).

mRNA has 4 nucleotide bases like DNA, but instead of Thymine (T) it has Uracil (U).

Transcription produces a single strand of mRNA.

DNA Transcription

mRNA strand

DNA Transcription

The completed mRNA strand leaves the nucleus via a nuclear pore and goes into the cytoplasm.