Warm up
1. Highlight all of the proteins listed on your
visual.
2. Underline what proteins provide for your
body?
Protein Synthesis
What does the word synthesis mean?
Synthesis means “to make”.
Therefore, protein synthesis means what?
to make proteins
Amino Acids
___________
are the monomers
(small units) which make up the
polymer Proteins.
DNA’s role in Protein synthesis
•DNA is in the nucleus and
has the instructions (genetic
code) for making the protein
•The organelle that proteins
are made on is the ribosome
• However, DNA cannot leave
the nucleus to get the
instructions to the ribosome.
•Therefore, it has to send a
messenger called
messenger RNA (mRNA)
ribosome
DNA
There are two steps in protein synthesis:
Step 1: Transcription
Step 2: Translation
TRANSCRIPTION
“writing the instructions”
• During Transcription,
mRNA makes a copy of
DNA in it’s own language
• mRNA’s language does
not include the nitrogen
base, thymine (T) instead
it has uracil (U)
• Transcription takes place
in the nucleus of the cell
Transcription Practice
Transcribe the following DNA strand to an RNA strand:
DNA: T A C G G A G T G C T C G C A C G C G A T A C T
mRNA: A U G C C U C A C G A G C G U G C G C U A U G A
Codons and anticodons consist of 3 nucleotides.
How many codons are on the above mRNA strand? 8
Now mRNA can take it’s copy of the DNA code to the
ribosome
________________
where proteins are made
mRNA travels from nucleus
to the ribosome in the cytoplasm
preparing for Translation.
Nucleus
mRNA
Summarize the
Transcription Process
Translation
“read the instructions”
Translation involves
transfer RNA (tRNA)
which transfers the
amino acid to the
ribosome where
mRNA awaits
The key components
of the tRNA molecule
that are important
during translation are
amino acids and
anticodons
TRANSLATION
• In order for this process
to take place, the
anticodons of the tRNA
must read and bind to
the codons on the mRNA
strand
• When the anticodons and
codons bind together,
the tRNA releases it’s
amino acid
TRANSLATION
• Each released amino acid is
held together by a peptide
bond therefore making
polypeptides.
• The sequence of amino
acids determine the shape
and type of polypeptide or
protein being made.
• Proteins are made of one
or more polypeptides.
Polypeptide / Protein
Peptide
Bond
In order to simulate the process of Translation,
you must correctly read the following mRNA
genetic code chart
Translation Practice
Using the mRNA genetic code chart, translate the
following mRNA strand
mRNA: A U G C C U C A C G A G C G U G C G C U A U G A
Protein: met - pro - his - glu - arg - ala - leu - stop
Summarize the
Translation Process
Are you ready to interpret which
process is taking place in the
following diagrams?
Transcription or Translation
Transcription or Translation
Transcription or Translation
Transcription or Translation
Transcription or Translation
Transcription or Translation
Transcription or Translation
Think Pair Share
Tell your neighbor what happens
during the process of protein synthesis
using the visual summary
Protein Synthesis Animations
http://www.wisc-online.com/objects/index_tj.asp?objID=AP1302
http://www.lew-port.com/10712041113402793/lib/10712041113402793/Animations/Protein%20Synthesis%20%20long.swf
\\centraldata\ETSD\Intro to Human Genetics (D)
Practice Question
The diagram shows how a section of protein containing the amino acid
sequence QYWQ is formed. What is the nucleotide sequence of the mRNA
section shown?
A.
B.
C.
D.
5′UCGGAUACUACU3′
5′CCACCACCACCA3′
5′ACUUCGGAUACU3′
5′CAGUAUUGGCAA3′