Name:
SBI4U: 3-4 Central Dogma Assignment
(25 Marks)
Knowledge/Understanding
(K/U)
Thinking/Inquiry
(T/I)
Application (A)
Communication (C)
/25
Instructions: For questions 1-5 write your answers on the “Central Dogma Answer Page”. For
Questions 6-9 answer on a separate piece of paper.
The following is the base sequence on the coding strand of a DNA molecule.
AAT GCC AGT GGT TCG CAC
1. Rewrite the base sequence and underneath write the base sequence for the template
DNA strand. (1 mark)
2. Write the base sequence for the strand of mRNA transcribed from the original strand of
DNA. (1 mark)
3. Write the amino acid sequence translated from this mRNA. (1 mark)
a) If the fourth nucleotide in the coding DNA strand was changed from a G to a C, what
would be the base sequence of the new strand of mRNA? (1 mark)
b) What would the resulting amino acid fragment be? (1 mark)
4. Analyze the result of an addition mutation:
a) If a G were added to the coding DNA strand after the third nucleotide, what would
be the base sequence of the resulting coding DNA strand, Template strand and
mRNA? (3 marks)
b) What would the resulting amino acid fragment be? (2 mark)
5. Analyze the result of a substitution mutation:
a) If the eighth nucleotide in the coding DNA strand was changed from G
to C, what would the resulting mRNA be? (1 mark)
b) What would the resulting amino acid sequence be? (2 marks)
6. Make a drawing of the coding strand of mRNA using these symbols: (3 marks)
A
C
U
G
SBI4U: 3-4 Central Dogma Assignment
R
P
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Name:
7. The image below shows the amino acid sequence for the human insulin protein.
a) Decode Chain A for human insulin shown below. List the RNA bases required to make
insulin. Print clearly and in large letters. Leave a space between each triplet for ease of
reading. Note: Many amino acids have more than one triplet combination. You may
choose which triplet to use for these amino acids.
(2 marks)
Example:
Gly - GGU
Ile - AUU
Val - GUG
8. On the diagram below, what do the capital S’s with lines between them represent? (1
mark)
9. Apply your understanding of the central dogma of genetics to create an analogy that
compares the transcription and translation process of real-life processes. (6 marks)
INSULIN – Amino acid sequences for A & B Chains
SBI4U: 3-4 Central Dogma Assignment
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Name:
ANSWERS – SBI4U Central Dogma Assignment
1. Coding DNA:
AAT GCC AGT GGT TCG CAC
Template DNA:
TTA CGG TCA CCA AGC GTG
2. mRNA:
AAU GCC AGU GGU UCG CAC
3. amino acids:
AAC GCC AGU GGU UCG CAC
(1 mark)
(1 mark)
Asn Ala Ser Gly Ser His
3a. mRNA:
AAT CCC AGT GGT TCG CAC
AAU CCC AGU GGU UCG CAC
3b. amino acids
AAU CCC AGU GGU UCG CAC
Asn Pro Ser Gly Ser His
4. Mutation 1 (Addition Mutation)
a) Coding DNA:
(1 mark)
Template DNA:
(1 mark)
mRNA:
(1 mark)
b) amino acids:
(2 marks)
5. Mutation 2 (Substitution Mutation)
a) mRNA
SBI4U: 3-4 Central Dogma Assignment
(1 mark)
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Name:
b) amino acids:
(2 marks)
9. Central Dogma using the Chef:
Recipe (DNA): A recipe is similar to DNA in the culinary arts. It includes all of the directions
required to prepare a dish. In a similar vein, the genetic instructions needed to create and
maintain living things are found in DNA.
Cookbook (Genome): An assortment of recipes is called a cookbook. The genome, which has
all the genes (recipes) required for an organism, is compared to a cookbook in the field of
genetics.
TRANSCRIPTION
1. Preparation (Initiation): A chef must first prepare the ingredients before beginning to
cook. When it comes to transcribing, commencement is similar to a chef assembling the
elements for a dish.
2. Cooking (Elongation): The chef (RNA polymerase) follows the DNA recipe during
transcription to produce a temporary copy (mRNA). This procedure is similar to a chef
preparing a dish as directed by the recipe.
3. Finishing (Termination): The meal is ready when the chef is done preparing it. When the
mRNA copy is finished and detached, transcription is said to have terminated.
TRANSLATION;
1. Recipe Review; after the chef has prepared a dish, someone else needs review the recipe
(initiation). In translation, initiation is similar to the ribosome, or reviewer, beginning to
read the recipe (mRNA).
2. Assembly Line (Elongation): To recreate the chef's food on a wider scale, several cooks
are arranged in an assembly line, all of them using the same recipe. In a similar manner,
the ribosome reads the mRNA and puts together amino acids to form proteins during
translation.
3. Final Dish (Termination): Translation yields a full protein; much like an assembly line
yields a final dish. Termination in translation is similar to the cook completing and serving
the meal.
To sum everything up, the flow of genetic information is displayed by the chef's routine.
Just as a chef follows a recipe to produce a dish, the recipe (DNA) is transcribed into a
temporary copy (mRNA), and this copy is then translated into a final product (protein).
SBI4U: 3-4 Central Dogma Assignment
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