Use the
SUMMARY OF PROTEIN SYNTHESIS
handout during this section of notes.
The part of the DNA molecule that holds the
code for the future protein unwinds and unzips
1.

Nucleotides used in the synthesis of mRNA begin
moving towards the coding strand of DNA
The mRNA chain is synthesized and is
complementary to the coding DNA strand
2.

TRANSCRIPTION
The mRNA code moves to a ribosome in the
cytoplasm
tRNA molecules each possess an anti-codon that
aligns opposite the complementary codons on
the mRNA strand
3.
4.

Each tRNA brings with it a specific amino acid.
5.
The ribosome moves down the mRNA strand
 The ribosome begins to read the
mRNA in 3 nucleotide chunks
(TRANSLATION)


Once it finds the sequence AUG it will
begin calling for tRNA molecules to
bring amino acids.

AUG is called the initiator codon

UGA, UAA, UAG
This will continue until the ribosome
reads a terminator codon
The ribosome moves down the mRNA strand
5.




tRNA molecules align in the sequence dictated by
the triplet codon on the mRNA
Amino acids from tRNA’s bond together
Empty tRNA returns to cytoplasm to pick up
another amino acid
When ribosome reaches the end of the mRNA
strand, it falls off leaving behind a number of
amino acids that are linked together to form a
protein.