Transcription and translation workbook
A great place to start: What makes a firefly glow? http://learn.genetics.utah.edu/content/begin/dna/firefly/
1.
State the central dogma of genetics.

2.
Transcription and translation is also known as protein synthesis, and is the expression of genes. The genetic code
determines the amino acid sequence of a polypeptide, and the properties of the amino acids give the final structure
and function of the protein.
Other than membrane proteins, state four functions of proteins in the cell.



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3.
Protein synthesis relies on RNA as a messenger and translating molecule.
Compare the structures of DNA and RNA.
DNA
Similarities:
RNA
Differences:
4.
Compare the processes of transcription and translation.
Transcription
Begins with…
mRNA
Ends with…
Location
Uses…
Translation
RNA polymerase
5.
Describe the genetic code:
Molecule used
Function
Codon
A set of three bases, complementary to the DNA triplet
Start codon
Stop codon
6.
Distinguish between triplets and codons.
 Triplets:

Codons:
Transcription Review
7.
How many different kinds of bases can be found on DNA ?
8.
What base is found on RNA but not on DNA?
9.
How many bases are in a codon?
10. In an anticodon?
11. The process of making mRNA from DNA is called ___________________ and it occurs in the __________________
12. When messenger RNA (mRNA) is being made the RNA base________ always pairs with which DNA base__________
13. What is the product of transcription?
14. To what part of the cell do the products of transcription travel?
15. Consider the following DNA strand:
TAC CGT TCT GCT AAA TAT ACC ACT
Write the sequence of bases for the product of transcription here: Remember! transcription produces RNA using
the DNA strand as a template!
16. What is the third codon in the mRNA you produced in?
Translation
17. Distinguish between mRNA and tRNA.
 mRNA
 tRNA
18. Transcribe and translate this DNA sequence.
DNA T A C G G G C C
C
G
T
G
A
C
A
G
C
C
mRNA
Amino acid
19. Quick mathematical questions:
a. An mRNA strand has 76 codons. How many amino acids will be in the polypeptide?

b. A polypeptide contains 103 amino acids. What is the length of the gene (unit = base pairs)?

20. Deduce the amino acids translated from these mRNA codons, using the table. Start in the middle.
AUG =
CAG =
UCA =
GAC =
AAA =
21. Explain the significance of the following:
The genetic code is universal.



The genetic code is degenerate.




A
C
T
Translation Review
22. The process of assembling a protein from mRNA is called _________________ and it occurs in the
___________________
23. Which organelle is involved in translation?
24. How many bases are in an anticodon?
25. How many amino acids are attached to a single transfer RNA?
26. Distinguish between the term codon and anitcodon.
Tip: Remember that the sequence of codons specifies the sequence of amino acids. Thus always translate the codons
which are only on mRNA.
Transcription & Translation Colouring
Transcription
RNA, Ribonucleic Acid is very similar to DNA. RNA normally exists as a single strand (and not the double stranded double
helix of DNA). It contains the same bases, adenine, guanine and cytosine. However, there is no thymine found in RNA,
instead there is a similar compound called uracil.
Transcription is the process by which RNA is made from DNA. It occurs in the nucleus. Label the box with the x in it near
the nucleus with the word TRANSCRIPTION and proceed to color the bases according to the key below
Thymine = orange
Uracil = brown
Cytosine = yellow
Adenine = dark green
Guanine = purple
Color the strand of DNA dark blue (D) and the strand of RNA light blue (R).
Color the nuclear membrane (E) gray.
Translation
Translation occurs in the cytoplasm, specifically on the ribosomes. The mRNA made in the nucleus travels out to the
ribosome to carry the "message" of the DNA. Here at the ribosome, that message will be translated into an amino acid
sequence.
Color the ribosome light green (Y)
Note how the RNA strand threads through the ribsosome like a tape measure and the amino acids are assembled. The RNA
strand in the translation area should also be colored light blue, as it was colored in the nucleus.
Label the box with the X in the translation area with the word TRANSLATION.
Important to the process of translation is another type of RNA called Transfer RNA (F) which function to carry the amino
acids to the site of protein synthesis on the ribosome.
Color the tRNA red.
A tRNA has two important areas. The anticodon, which matches the codon on the RNA strand. Remember that codons are
sets of three bases that code for a single amino acid.
Make sure you color the bases of the anticodon the same color as the bases on your DNA and RNA strand - they are
the same molecules!
At the top of the tRNA is the amino acids. There are twenty amino acids that can combine together to form proteins of all
kinds, these are the proteins that are used in life processes. When you digest your food for instance, you are using enzymes
that were originally proteins that were assembled from amino acids. Each tRNA has a different amino acid which link
together to form a polypeptide.
Color all the amino acids (M) pink.
From DNA to protein
DNA is copied by a process called ______________ which occurs in the _____________ of
the cell. Only _____________ strand of DNA is copied, which contains the relevant gene.
The copied strand is called ___________________ . Transcription requires two enzymes_________ and _________. In mRNA, the base T is replaced by ______.
HIGHER LEVEL
The pre-mRNA is then ________ to remove non-coding sequences called ________. This
requires a complex of enzymes called the ______________. The resulting mature mRNA
exits the nucleus via the _______ ______.
The copied strand leaves the nucleus and is decoded at a ____________ which are found
in the cytoplasm. This process is known as ____________. Each sequence of three bases,
known as a __________, codes for a particular _________________ which is brought to
the ribosome by _________________________ molecules.
The _________on tRNA binds to the complementary codon on mRNA to ensure the correct
amino acid is bought over. The amino acids are joined together using energy from ATP and
an __________. When a _________codon is reached, translation is terminated and the
resulting amino acid chain folds in to a _________.
Spliced
Nucleus
Protein
Translation
One
Nuclear pore
Spliceosome
Amino acid
Transcription
Intron
Ribosome
Anticodon
Codon
Enzyme
pre- mRNA
Stop
Uracil
Transfer RNA
RNA polymerase
DNA helicase
Glossary of Key Terms for Protein Synthesis
1.
4.
a sequence of three ribonucleotides on a tRNA that are complementary to a codon on the
mRNA; codon-anticodon binding results in the tRNA bringing the correct amino acid to the site
of protein synthesis.
a term describing the polarities of the two strands of the DNA double helix; on one strand,
the sugar-phosphate backbone advances in the 5’  3’ direction while on the opposite,
complementary strand, the sugar phosphate backbone advances in the 3’  5’ direction.
a hydrogen-bonded pair of bases within the DNA double helix; the standard base pairs always
involve a purine and a pyrimidine; in particular, adenine always base pairs with thymine and
cytosine with guanine.
The form in which eukaryotic cells store their DNA
5.
DNA  RNA  Protein.
6.
a piece of DNA that carries all the genetic instructions for a protein
7.
a group of three ribonucleotides on the mRNA that specifies the addition of a specific amino
acid onto the growing peptide chain.
8.
the opposite strands of the double helix are hydrogen bonded to one another such that
adenine and thymine or guanine and cytosine are always paired.
9.
a term used to describe the fact that different triplet codons may be used to specify a single
amino acid.
10.
the nucleic acid molecule that carries all of the genetic information of an organism; the
molecule is a double helix composed of two strands, each of which is composed of phosphate
groups, 2’-deoxyribose, and the nitrogenous bases thymine, cytosine, adenine, and guanine.
a nucleotide composed of a nitrogenous base in glycosidic linkage to the carbon of the sugar
2’-deoxyribose and with one phosphoryl groups
2.
3.
11.
12.
the enzyme that catalyzes the polymerization of daughter DNA strands using the parental
strand as template.
13.
the spiral staircase-like structure of the DNA molecule characterized by two sugar-phosphate
backbones wound around the outside and nitrogenous bases extending into the center
14.
the complete set of genetic information in all the chromosomes of an organism
15.
the DNA strand that is replicated discontinuously
16.
the DNA strand that is replicated continuously
17.
an RNA species produced by transcription, which specifies the amino acid sequence for a
protein.
18.
a molecule composed of a nitrogenous base, a five-carbon sugar, and one, two, or three
phosphoryl groups.
19.
(single-stranded nucleic acid molecules that are composed of phosphate groups, ribose, and
the nitrogenous bases uracil, cytosine, adenine, and guanine.
20.
a nucleotide composed of a nitrogenous base in -N-glycosidic linkage to the 1' carbon of the
sugar ribose and with one, two, or three phosphoryl groups esterified at the hydroxyl of the 5'
carbon of the ribose.
an organelle composed of a large and a small subunit, each of which is made up of ribosomal
RNA and proteins; it functions as a platform on which translation can occur and has the
enzymatic activity that forms peptide bonds.
the enzyme that catalyzes the synthesis of RNA molecules using DNA as a template.
21.
22.
23.
24.
25.
26.
DNA polymerase reads each parental strand of DNA and produces a complementary daughter
strand; thus, all newly synthesized DNA molecules consist of one parental and one daughter
strand.
the synthesis of mRNA from a DNA template.
small RNAs that bind to a specific amino acid at the 3' end and mediate its addition at the
appropriate site in a growing peptide chain; this is accomplished by recognition of the correct
codon on the mRNA by the complementary anticodon on the tRNA.
the synthesis of a protein from the genetic code carried on the mRNA; the process occurs on
ribosomes and the code of the mRNA is decoded by the anticodon of the tRNA.
gene
tRNA
nucleotide
codon
ribonucleotide
mRNA
translation
RNA polymerase
anti-parallel strands
genome
transcription
lagging strand
base pair
ribonucleic acid (RNA)
DNA polymerase
double helix
complementary strands
central dogma
degenerate code
leading strand
chromosome
deoxyribonucleotide
ribosome
deoxyribonucleic acid (DNA)
semi-conservative replication
anti-codon