Download Central Dogma Activity Worksheet

Name:_______________________________________ Date:________________ Period:_____
Central Dogma Lab Activity
Introduction:
Every cell in your body has the same "blueprint" or the same DNA. Like the blueprints of a house tell the builders how to
construct a house, the DNA "blueprint" tells the cell how to build the organism. Yet, how can a heart be so different
from a brain if all the cells contain the same instructions? A cell has the ability to turn off most genes and only work
with the genes necessary to do a job. Remember, a gene is section of DNA that codes for a specific trait.
Pre-Lab Questions:
1. What is a gene? _____________________________________________________________________
2. Where are chromosomes/chromatin located in a eukaryotic cell? _________________
3. What nitrogen bases are found in DNA? ____, ____, ____, ____ In RNA? ____, ____, ____, ____
4. How many strands does DNA have? ______ RNA? ______
Circle the underlined words below that correctly completes the sentence.
5. mRNA is synthesized in transcription / translation.
6. mRNA has codons / anti-codons.
7. tRNA brings amino acids to the nucleus / ribosomes.
8. tRNA has codons / anti-codons.
9. tRNA transfers amino acids during transcription / translation.
10. Ribosomes are the site of where transcription / translation takes place.
Objective:
In this lab activity, you will explore the flow of information from DNA to Gene Expression and practice
transcription and translation.
Procedure:
1. Place the cards in the appropriate boxes on the CENTRAL DOGMA mat on the lab table.
2. Record you answers below. You only need to write the letters of the cards in the boxes below.
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3. In the simulation below, you will examine the DNA sequence of a fictitious organism: the Snork. Snorks
were discovered on the planet Dee Enae. Snorks only have one chromosome with 3 genes. Your job is
to analyze the genes of its DNA and determine the traits.
Snork DNA and Traits
Amino Acid
Number
20
16
2
4
11
5
8
9
12
13
Codon
AUG
UCG
AAC
UUG
GGG
CCC
UUU
AAA
CCA
AUA
Amino Acid
Sequence
20-11-13
20-12-13
16-2-5
16-4-5
9-8-8
9-4-8
Trait
Hairless
Hairy
4-legged
2-legged
Round Body
Square Body
4. Below you will find the chromosome from a Snork. Each gene has only 3 amino acids that code for it.
Your job is to determine the sequence of amino acids for your specimen. In the chart below, write
down the complimentary mRNA, the amino acid sequence mRNA codes for, and the related trait.
*Be sure to use the mRNA on the codon chart above.*
Draw your Snork. Be creative!
DNA
TACGGTTAT
- AGCAACGGG -
mRNA
-
-
Amino
Acids
-
-
Trait
-
-
TTTAACAAA
STAAR Practice Questions:
_____ 1 Which of the following describes the function of DNA?
A encoding genetic information
B storing energy in chemical bonds
C speeding up biochemical reactions
D destroying substances that enter the cell
_____ 2 Which of these best describes the correct sequence in the expression of a trait?
A trait  gene enzyme
B gene  protein  trait
C protein  gene  trait
D gene  trait  DNA
_____ 3 Transfer RNA molecules pick up amino acids which are free in the cytoplasm and carry them to? [NY EOC]
A lysosomes
B chromosomes
C nuclei
D ribosomes
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_____ 4 Which factor most affects the order of amino acids in a protein?
A the DNA located in the nucleus of the cell
B the cell in which the protein is located
C the amount of ATP available for the cell’s use
D the area in a cell where proteins are produced
_____ 5 Looking at the diagram above, which label represents the coding part of DNA?
A 1
B 2
C 3
D all of the above
_____ 6 Which molecule is paired with its correct role in protein synthesis?
A nucleus – forms peptide bonds
B ribosome – carries DNA instructions
C mRNA – joins amino acids
D tRNA – transfers amino acids
E DNA – leaves the nucleus
[TN09 EOC]
_____ 7 How do the functions of DNA and RNA differ? [AR08 EOC]
A DNA directs protein transport, while RNA aids in energy production.
B DNA aids in energy production, while RNA directs protein transport.
C DNA stores genetic information, while RNA relays genetic information for protein synthesis.
D DNA relays genetic information for protein synthesis, while RNA stores genetic information.
_____ 8 Which relationship is most similar to the relationship below?
tRNA : ribosome
A book : publisher
B truck : factory
C key : lock
D baker : pie
E boss : workers
[NC08 EOC]
_____ 9 Carol and her mom have similar noses, eyes, and hands. Which of the following explains why
Carol and her mom have similar traits?
A Carol inherited DNA from her mom only
B Carol inherited chromosomes from her mom only
C Carol inherited the genes that code for these traits from her mom
D Carol inherited the proteins that code for these traits from her mom
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Transcription – Translation Practice
Directions: This is a gene, a section of DNA. Fill in the missing DNA & RNA nitrogen bases using the base pairing rules.
When filling in mRNA, use the coding strand of DNA. Translate the mRNA codons and find the amino acids using the
Genetic Code chart.
coding
strand
The Genetic Code
Remember: *
Use mRNA
when reading
the Genetic
Code chart.
Fill in the sequence of the Central Dogma below:
___________ → ___________ → amino acids → _________________ → ________________________________
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