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TRANSCRIPTION AND
TRANSLATION
Bell Ringer (5 MINUTES)
1. Have your homework out on your
desk and ready to turn in
2. Draw and label a nucleotide.
3. Summarize the steps of DNA
replication.
TURN AND TALK
 If
DNA is universal,
then why do we as
humans look
different from other
living things?
PART 1: TRANSCRIPTION
To transcribe means to
put information into a
written form
What are we learning today?
Benchmark
Objectives
SC.912.L.16.5 – Explain
the basic processes
of transcription and
translation, and how they
result in the expression of
genes.
 Compare and
contrast RNA and
DNA.
 Describe the
processes of
transcription and
translation.
Introduction
• From DNA to protein
• https://www.youtube.com/watch?v=gG7uCsk
UOrA
What is the essential vocabulary?

RNA polymerase – enzyme that binds to DNA
and separates the DNA strands during
transcription.

Transcription – Process during
which RNA molecules are produced
by copying part of the nucleotide
sequence of DNA.

Intron – sequence of DNA that is not
involved in coding for a protein.

Exon – sequence of DNA that is
involved in coding for a protein.
How is DNA like or not like RNA?



RNA and DNA are nucleic acids.
RNA, like DNA consist of a
long chain of nucleotides.
There are three main
differences between RNA
and DNA:
 The sugar in RNA is
ribose, the sugar in DNA
is deoxyribose.
 RNA is single stranded,
DNA is double stranded.
 RNA contains uracil (U)
DNA contains thymine (T)
What are the three types of RNA?
Abbrev.
mRNA
tRNA
rRNA
Name
Function
Carries instructions for
Messenger
making proteins from DNA
RNA
to ribosomes.
Transfer
RNA
Structure
Singlestranded
Reads mRNA sequence and
transfers each amino acid to A clover leaf
the ribosome.
Binds amino acids together
Ribosomal
to make a peptide chain
RNA
(protein)
Complex,
with
proteins
How does transcription works?
1.
Initiation: RNA polymerase binds to DNA
and separates the DNA strands.
1.
Elongation: RNA polymerase uses one
strand of DNA as a template to add
nucleotides, making a strand of RNA.
1.
Termination: When RNA polymerase
reaches a stop signal in the DNA, the
DNA and new mRNA are released.
How does transcription work?
A certain gene has the following sequence of
nucleotides. From left to right, write the sequence of
the mRNA molecule transcribed from this gene.
DNA
mRNA
3’
GACAAGTCCA CAA TC
5’
Draw in your notebook what Mrs.
Franklin draws on the white board
PART 2:
TRANSLATION
To translate is to express
meaning in a different
language or to move
something from one place
to another
What is the essential vocabulary?

Genetic code – Instructions needed to convert
DNA into proteins.

Codon – Three consecutive nucleotides
that in mRNA that specify a single amino
acid.

Anticodon – Three adjacent nucleotides
located on tRNA that binds to
the mRNA codon

Translation – Protein
synthesis using mRNA as a template.
What is the essential vocabulary?

Amino acid – building block, or monomer,
of all proteins.

Ribosome – organelle in the cell that is in charge
of producing proteins

Polypeptide chain – a group of amino acids
joined together that form proteins
How do proteins function?

Proteins are made by joining amino acids together into long
chains, called polypeptides chains.
 Each polypeptide contains a combination of any or all of
the 20 different amino acids.
 The properties of a protein are determined by the specific
amino acids in a polypeptide chain and the order in which
different amino acids are joined together.
amino acid + amino acid
Protein
What is the genetic code?




The “language” of mRNA instructions is called the
genetic code.
RNA contains four different bases:
A, U, G, C.
The genetic code is read three
letters at a time, each three-letter
word is known as a codon.
There are 64 possible three-base codons.
Genetic Code Chart
How does a cell interpret DNA?

Consider the following
RNA sequence:
5’

3’
UCGCACGGU
This sequence will be read
three bases at a time as:
UCG – CAC – GGU

The codons represent the
following amino-acids.
Serine – Histidine – Glycine
How does a cell interpret DNA?
Consider the following RNA
sequence and identify the amino
acids it will code for.
5’
AUGCGCUUCUAA
Consider the following DNA
sequence and identify the
amino acids it will code for.
3’
CTTGGAATG
5’
3’
What is translation?




The decoding of an mRNA
message into a polypeptide
chain is known as translation.
Translation takes place on
ribosomes.
During translation, or
protein synthesis, the cell
uses information from
mRNA to produce proteins.
The cell uses all three main
forms of RNA during
translation.
How does translation work?

Messenger RNA is transcribed in the nucleus and
then enters the cytoplasm for translation.
How does translation work?
1. INITIATION
A ribosome attaches to an
mRNA molecule in the
cytoplasm and a tRNA
molecule carrying
methionine (start codon =
AUG) binds to ribosome.
How does translation work?
2. ELONGATION
As the ribosome reads each
codon of mRNA, it directs
tRNA with the matching
anticodon to bring the specific
amino acid into the ribosome.
One at a time, the ribosome
attaches each amino acid to
the growing chain.
How does translation work?
3. TERMINATION
The polypeptide chain
continues to grow until the
ribosome reaches a “stop”
codon (UGA, UAA, UAG) on
the mRNA molecule.
How does translation work?
4. DISASSEMBLY
Ribosome falls apart,
releasing both the newly
formed polypeptide and the
mRNA molecule, completing
the process of translation
Draw in your notebook what Mrs.
Franklin draws on the white board
Let’s Recap What We Learned
• https://www.youtube.com/watch?v=gG7uCsk
UOrA
Partner Work 30 MIN.
•
•
•
READ ALL THE INSTRUCTIONS!!!
Stay with your partner at your lab table and
DO NOT walk around the room
Before you ask for help, try to find the
answer on your own by looking in your
notes
Independent Practice 15 MIN.
Exit Ticket
Home Learning
• Make Frayer Models for
the processes of
transcription and
translation (one Frayer
Model for each)
• For each process
include:
1. Definition
2. Illustration
3. Steps
4. Importance in living
things