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Name _____________________________________________ Period ______
Mitosis Lab
Introduction
Mitosis can be observed in cells that are in a state of growth. In this lab, you will observe both plant and
animal cells, identify which stage of cell division the cells are in. You will also determine how much time is
spent in each stage of the cell cycle.
Procedure
1) Go to my Online Classroom and click on the Mitosis Lab link.
2) Click on “Click to View Whitefish Embryo.” Then click on the first image to enlarge it.
3) Draw an illustration of highlighted cell in Data Table 1.
4) Using the reference images, label your drawing as either interphase, prophase, metaphase, anaphase, or
telophase.
5) Repeat step 3 and 4 for the second, third, and fourth images.
6) Click on “Start Page.” Then choose “Click to View Onion Root Tip.”
7) Click on the first image.
8) Draw an illustration of the highlighted cell in Data Table 1 and label your drawing as either interphase,
prophase, metaphase, anaphase, or telophase. Then click the Back button.
9) Repeat step 8 for the second, third, fourth, and fifth images.
10) A wider sample of the onion root tip was looked at and the total number of each phase was counted.
These values are in Data Table 2. Using the formula below, calculate the percentage of cells in each
phase and these numbers in Data Table 2:
𝑃𝑒𝑟𝑐𝑒𝑛𝑡𝑎𝑔𝑒 𝑜𝑓 𝑐𝑒𝑙𝑙𝑠 𝑖𝑛 𝑝ℎ𝑎𝑠𝑒 = 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑐𝑒𝑙𝑙𝑠 𝑖𝑛 𝑝ℎ𝑎𝑠𝑒
𝑡𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑐𝑒𝑙𝑙𝑠 𝑥 100
Data/Results
Data Table 1:
Onion Root-tip Whitefish Blastula
Image 1
Image 2
Image 3
Image 4
Image 5
Data Table 2:
Phases Number of Cells Percentage
Interphase 20
Prophase 10
Metaphase 3
Anaphase 2
Telophase 1
Total 36 100%
Postlab Questions
1) Which stage of mitosis is the easiest (in your opinion) to identify? Why?
2) Which stage of mitosis is the hardest (in your opinion) to identify? Why?
3) How does mitosis differ from a plant cell to an animal cell?
4) Based on your data, which phase had the largest percentage of cells? The smallest percentage?
5) A chemical company is testing a new product that it believes will increase the growth rate of food
plants. Suppose you are able to view the slides of onion root tips that have been treated with the product.
If the product is successful, how might the slides look different from the slides you viewed in this lab?
DNA & Its Replication
Deoxyribonucleic Acid
o Deoxyribonucleic acid (DNA)—molecule that stores
________________________________________ in all organisms
o Composed of _______________________, which has three parts:
Phosphate group
Deoxyribose sugar
Nitrogen-containing base
Nucleotides
o ______________ different nucleotides
Differ based on the __________________________________
Discovery of Genetic Material
o Frederick Griffin
Concluded mystery material is “________________________________”
o Oswald Avery
Isolated “transforming principle”
Tests showed that DNA is genetic material
o Alfred Hershey & Martha Chase
Clarified Avery’s experiment
Showed that genetic material is _________________________________
Discovery of DNA’s Structure
o Erwin Chargaff
Relationship between nitrogen bases
o Rosalind Franklin
X-ray evidence of double helix
o Watson & Crick
Double Helix
o Double helix—model of DNA in which two strands wind around each other like a
twisted ladder
“Sides” are made up of alternating _______________________________
(sugar) molecules
“Rungs” are made up of _________________________________
Pairing of Nitrogen Bases
o ______________ (A) pairs with thymine (T)
o Cytosine (C) pairs with ________________ (G)
DNA Replication
o DNA Replication—the process by which _____________________ during the
cell cycle
Copy needed for cell reproduction
Each new cell will have an _______________ of the original DNA
Occurs during _____________ of cell cycle
o Enzymes unzip the double helix so that two strands of DNA are separated and
individual nucleotides are exposed
Area known as origin of replication
o DNA polymerase—a group of enzymes that
_______________________________________________________________
Adds free floating nucleotides to create new strand of DNA
____________________________ to original strand
o Two identical DNA molecules are created
Each molecule has
____________________________________________________________
Considered ____________________________________
Name ________________________________________________ Period ______
DNA Stations
In this activity you will work through three different stations to learn about the structure of DNA,
simulate how DNA replicates, and isolate your own DNA.
Station #1: DNA Structure Coloring
Complete the DNA sequence on the molecule below (remember A pairs with T and G pairs with
C). Then color the following components of the structure:
Phosphates (P)
Deoxyriboses (D)
Adenine (A)
Thymine (T)
Guanine (G)
Cytosine (C)
Hydrogen bonds
A
C
T
G
A
G
G
A
C
C
G
Station #2: DNA Replication Simulation
Using the sample of DNA on the left,
(a) Rewrite the Original Strand 1 in the middle column.
(b) Rewrite the Original Strand 2 in the right column.
(c) Write the new strand in each the middle and right columns (remember A pairs with T and
G pairs with C).
Original
DNA
Strand 1
Original
DNA
Strand 2
→
Original
DNA Strand
1
New DNA
Strand
+
New DNA
Strand
Original
DNA
Strand 2
T A
A T
A T
T A
G C
T A
C G
G C
A T
C G
C G
G C
C G
T A
G C
G C
T A
C G
C G
A T
A T
G C
T A
C G
C G
T A
T A
T A
G C
A T
Using the above model of DNA replication, explain why DNA replication is described as
semiconservative.
Station #3: Isolating Your DNA
1) Get about 5 mL of clear Gatorade in a dixie cup. Then swish the clear Gatorade around in
your mouth for about 30 seconds.
2) Spit the solution back into the Dixie cup.
3) Add ~2 mL of soap (two squirts of the plastic pipet) into the cup carefully. Try not to
make any bubbles.
4) Gently mix the Gatorade-soap solution for 2-3 minutes. Again try not to make any
bubbles. What do your solution look like?
5) Tilt your Dixie cup slightly and carefully add ~8 mL of cold rubbing alcohol. There
should be two layers in the Dixie cup. Make sure not to mix these layers.
6) Let the solution sit for 1-2 minutes.
7) While the solution is sitting, get a microcentrifuge tube and fill it about ½ full with cold
rubbing alcohol.
8) You should see a white substance on the top layer; this is your DNA. Use a toothpick to
spool the DNA.
9) Once you have gotten most of the DNA around the toothpick, gently swirl the toothpick
in the microcentrifuge tube filled with rubbing alcohol to transfer the DNA.
10) Close the lid of the microcentrifuge tube. Get a piece of string and tie it around the lid of
the microcentrifuge tube. You now have a necklace of your own DNA.
11) Answer the following questions:
(a) Are you looking at a single strand of DNA? Why or why not?
(b) Soap was used to break apart the cell membrane of your cheek cells. Why does this
need to be done?
(c) Why would you need to extract human DNA? Give at least two reasons and/or
examples.
Deoxyribonucleic acid molecule that stores genetic
information in all organisms
DNA replication the process by which DNA is
copied during the cell cycle
DNA polymerase a group of enzymes that bound
the new nucleotides together
Gene
a piece of DNA that provides a
set of instructions to a cell to
make a certain protein
Ribonucleic acid
nucleic acid molecule that allows
for the transmission of genetic
material information and protein
synthesis
Messenger RNA
form of RNA that carries genetic
information from the nucleus to
the ribosome, serving as a
template
Transfer RNA form of RNA that brings amino
acids to ribosomes
Ribosomal RNA
RNA in the ribosome which helps
join mRNA and tRNA to make
proteins
Transcription
the process of copying a sequence
of DNA to produce a
complementary strand of RNA
RNA polymerase
enzymes that bond nucleotides
together in a chain to make a new
RNA molecule
Translation process that converts an mRNA
message into a protein
Codon a three-nucleotide sequence that
codes for an amino acid
Anticodon a set of three nucleotides that is
complementary to an mRNA
codon
Exon nucleotide segments that code for
parts of a protein
Intron nucleotide segments that
intervene between exons
Biotechnology use and application of living
things and biological processes
Genetic engineering
the changing of an organism’s
DNA to give an organism new
traits
Recombinant DNA DNA that contains genes from
more than one organism
Restriction enzyme
an enzyme that cuts DNA
molecules at a specific nucleotide
sequence
Plasmid
closed loops of DNA that are
separate from the bacterial
chromosome and that replicate on
their own within the cell
Clone a genetically identical copy of a
gene or of an organism
Polymerase chain reaction
a technique that produces millions
or billions of copies of a specific
DNA sequence in just hours
DNA fingerprint
a representation of parts of an
individual’s DNA that can be
used to identify a person at the
molecular level
Gene sequencing
determining the order of DNA
nucleotides in genes or in
genomes
Gene therapy
the replacement of a defective or
missing gene, or the addition of a
new gene, into a person’s genome
to treat a disease
Name _____________________________________________________ Period ______
From DNA to Protein Vocabulary Preview
Matching
Match the following terms with the appropriate definitions:
(a) Anticodon
(b) Biotechnology
(c) Clone
(d) Codon
(e) Deoxyribonucleic acid
(f) DNA fingerprint
(g) DNA polymerase
(h) DNA Replication
(i) Exon
(j) Gene
(k) Gene sequencing
(l) Gene therapy
(m) Genetic engineering
(n) Intron
(o) Messenger RNA
(p) Plasmid
(q) Polymerase chain reaction
(r) Restriction enzyme
(s) Ribonucleic acid
(t) Ribosomal RNA
(u) RNA polymerase
(v) Transcription
(w) Transfer RNA
(x) Translation
1) closed loops of DNA that are separate from the bacterial chromosome and that replicate on their own
within the cell
2) a genetically identical copy of a gene or of an organism
3) a technique that produces millions or billions of copies of a specific DNA sequence in just hours
4) a representation of parts of an individual’s DNA that can be used to identify a person at the molecular
level
5) molecule that stores genetic information in all organisms
6) RNA in the ribosome which helps join mRNA and tRNA to make proteins
7) the process of copying a sequence of DNA to produce a complementary strand of RNA
8) an enzyme that cuts DNA molecules at a specific nucleotide sequence
9) determining the order of DNA nucleotides in genes or in genomes
10) the process by which DNA is copied during the cell cycle
11) a group of enzymes that bound the new nucleotides together
12) a piece of DNA that provides a set of instructions to a cell to make a certain protein
13) nucleic acid molecule that allows for the transmission of genetic material information and protein
synthesis
14) enzymes that bond nucleotides together in a chain to make a new RNA molecule
15) process that converts an mRNA message into a protein
16) a three-nucleotide sequence that codes for an amino acid
17) a set of three nucleotides that is complementary to an mRNA codon
18) nucleotide segments that code for parts of a protein
19) nucleotide segments that intervene between exons
20) use and application of living things and biological processes
21) the changing of an organism’s DNA to give an organism new traits
22) DNA that contains genes from more than one organism
23) form of RNA that carries genetic information from the nucleus to the ribosome, serving as a template
24) form of RNA that brings amino acids to ribosomes
25) the replacement of a defective or missing gene, or the addition of a new gene, into a person’s genome to
treat a disease
Crossword
Using the words and definitions from the
previous page, complete the following
crossword.
Across
2) determining the order of DNA
nucleotides in genes or in genomes
4) DNA that contains genes from more than
one organism
8) a set of three nucleotides that is
complementary to an mRNA codon
14) a technique that produces millions or
billions of copies of a specific DNA
sequence in just hours
15) a genetically identical copy of a gene or
of an organism
16) use and application of living things and
biological processes
18) a group of enzymes that bound the new
nucleotides together
19) nucleic acid molecule that allows for
the transmission of genetic material
information and protein synthesis
22) the process by which DNA is copied
during the cell cycle
23) form of RNA that carries genetic
information from the nucleus to the
ribosome, serving as a template
24) a three-nucleotide sequence that codes
for an amino acid
25) process that converts an mRNA
message into a protein
Down
1) an enzyme that cuts DNA molecules at a specific nucleotide sequence
3) nucleotide segments that code for parts of a protein
5) a representation of parts of an individual’s DNA that can be used to identify a person at the molecular level
6) form of RNA that brings amino acids to ribosomes
7) molecule that stores genetic information in all organisms
9) nucleotide segments that intervene between exons
10) the changing of an organism’s DNA to give an organism new traits
11) the process of copying a sequence of DNA to produce a complementary strand of RNA
12) enzymes that bond nucleotides together in a chain to make a new RNA molecule
13) a piece of DNA that provides a set of instructions to a cell to make a certain protein
17) RNA in the ribosome which helps join mRNA and tRNA to make proteins
20) closed loops of DNA that are separate from the bacterial chromosome and that replicate on their own within the cell
21) the replacement of a defective or missing gene, or the addition of a new gene, into a person’s genome to treat a
disease
Protein Synthesis & Regulation
Central Dogma
o Central dogma—theory that states information flows in one direction from
_________________________________________________
Overview of Protein Synthesis
o Function: _____________________________
Proteins have many functions (support structure, enzymes)
Workhorse of cell
Gene—a piece of DNA that provides a set of instructions to a cell to make a certain
protein
o Two steps:
Transcription (_____________________)
Translation (______________________)
RNA
o Ribonucleic acid (RNA)—nucleic acid molecule that allows for the transmission of genetic
material information and protein synthesis
Assists with protein synthesis
Three differences from DNA:
Has ______________ instead of deoxyribose as sugar
_____________________ (instead of double-stranded)
Contains _______________ (U) instead of thymine
o
Types of RNA
o Three different types involved in protein synthesis
Messenger RNA (mRNA)—form of RNA that
_____________________________________ from the nucleus to the ribosome, serving
as a template
Transfer RNA (tRNA)—form of RNA that ________________________________ to
ribosomes
Ribosomal RNA (rRNA)—RNA in the ribosome which helps join mRNA and tRNA to
make proteins
Transcription
o Transcription—the process of copying a sequence of DNA to produce a complementary strand of
RNA
Similar to DNA replication
Enzymes using complementary base pairing
o RNA polymerase—enzymes that ____________________________________ in a chain to
make a new RNA molecule
Attaches to DNA at start of gene
o Starts to unzip DNA to expose nucleotides
o Complement RNA nucleotides are added together as RNA polymerase moves down one strand
of DNA
o RNA polymerases reaches the stop codon (stopping point)
____________________________, moving to cytoplasm
Translation
o Translation—process that converts an mRNA message into a protein
o
o Three steps
mRNA Sequence & Amino Acids
o Codon—a three-nucleotide sequence that _______________________________________
Found in DNA, which is than transcribed into mRNA (transcription)
o Two special codons:
Start codon—codon that signals the ________________________________; codes for
methionine
Stop codon—codon that ____________________________ of the amino acid chain
Genetic Code
o Sequence of codons dictates the order of amino acids in a protein
Genetic code chart ________________________________________________________
Translation Machinery
o Made up of three parts:
Ribosome → _____________________________________; three binding sites for tRNA
tRNA → brings the amino acid; contains anticodons to match mRNA
Anticodon—a set of three nucleotides that is
_________________________________________________________
mRNA → __________________________________________
Step #1: Initiation
o _____________________________________________ in the cytoplasm, forming translation
complex
o 1st tRNA (carrying Met) binds to mRNA in middle binding site
o Another tRNA matches up with exposed mRNA through anticodon in the last binding site
o _____________________________________ between two amino acids
Step #2: Elongation
o tRNA without amino acid leaves
o Another tRNA (matching next codon) comes in and process continues,
________________________________________________________________
o mRNA moves through ribosome (_______________________)
Step #3: Termination
o Stop codon is reached
o _________________________________, releasing mRNA and newly created protein
Gene Regulation
o Need for _______________ of what genes are _____________________ and when they are
______________
o Two methods:
Controlling transcription
Protein binds to DNA near gene, preventing transcription
Protein is released when that gene needs to be transcribed
o mRNA processing
Exon—nucleotide segments that _________________________________________
Intron—nucleotide segments that ________________________________________
All introns are removed
A cap and tail are added to mRNA before leaving nucleus
Name _________________________________________________ Period ______
Simulating Protein Synthesis
Genes are the units that determine inherited characteristics, such as hair color and blood type, along with
the structure of proteins that our cells make. The sequence of the amino acids in these proteins is decided by the
sequence of nucleotides in the DNA. In a process called transcription, which takes place in the nucleus of the
cell, messenger RNA (mRNA) reads and copies the DNA’s nucleotides sequences in the form of a
complementary RNA molecule. Then the mRNA carries this information in the form of a code to the ribosomes,
where protein synthesis takes place. The code words in mRNA, however, are not directly recognized by the
corresponding amino acids. Another type of RNA called transfer RNA (tRNA) is needed to bring the proper
amino acids; tRNAs arrive in turn and give up the amino acids they carry to the growing protein. The process
by which the information from DNA is transferred into the language of proteins is known as translation. In this
investigation, you will simulate the mechanism of protein synthesis and thereby determine the traits inherited by
fictitious organism called CHNOPS. CHNOPS, whose cells contain only one chromosome, are members of the
kingdom Animalia. A CHNOPS chromosome is made up of six genes (A, B, C, D, E, and F), each of which is
responsible for a certain trait. Then you will decipher a code in a DNA sequence to figure out the sentence in
this sequence.
CHNOPS Characteristics
Using the table below, determine the trait for each gene by:
Create the mRNA sequence using the complement base pairs (remember G pairs with C, A pairs with T,
and U pairs with A).
Then using the information in the left side of the table, figure out the amino acid sequence, based on the
mRNA sequence.
Finally identify the trait for that gene using the information in the right side of the table.
tRNA Triple Amino Acid Number Amino Acid
Sequence
Trait
UGG 20 20-11-13 Hairless
UCG 16 20-12-13 Hairy
GCU 2 20-21-21 Plump
UUG 4 13-14-15 Skinny
GCG 3 16-2 Four-legged
CCC 5 12-7-8-1 Long-nose
UCC 7 5-7-8-1 Short-nose
UUU 8 9-8 No freckles
AAA 9 9-4 Freckles
CCA 12 11-3-2 Blue skin
AUA 13 11-3-3 Orange skin
GGG 1 6-6-10 Male
UAG 6 6-6-14 Female
GAU 10
CCU 11
Gene A Gene B Gene C Gene D
DNA
Sequence ACC GGT TAT AGC CGA TTT AAC GGA CGC CGA
mRNA
Sequence
Amino Acid
Sequence
Trait
Gene E Gene F Sketch of CHNOPS
DNA
Sequence GGG AGG AAA CCC ATC ATC CTA
mRNA
Sequence
Amino Acid
Sequence
Trait
Now draw a sketch of your CHNOPS creature in the space above.
DNA Code Breaking
Pick one of the following sentences below. Using your genetic code chart, figure out the amino acid for each
codon (every group of three letters). Then use the table below to use the one letter abbreviation for the amino
acid. In the end, each DNA sequence will create a full sentence.
Amino Acid One Letter
Abbreviation Amino Acid
One Letter
Abbreviation Amino Acid
One Letter
Abbreviation
Alanine A Isoleucine I Arginine R
Cysteine C Lysine K Serine S
Aspartate D Leucine L Threonine T
Glutamate E Methionine M Valine V
Phenylalanine F Asparagine N Tryptophan W
Glycine G Proline P Tyrosine Y
Histidine H Glutamine Q Stop Space (-)
1) AGA TAC TAG GAC CTT ACT CGA TTG CTG ATT GCG CGA CTA TAA CGG TGC CTC ACT
CGG ATT AAC TAG TGC TGA AAT CTT ATT ACG GTA CTT CTC GCC ATC
2) TGC CTT TTA ATT CTF CGA ATA AGG ACT GAA CTC AAA TGT ATC TGG TAA GAC ATT
ACC CTT ACT CGG GCC CTT ATT AAG TCC CTC CTT
Name ________________________________________________ Period _____
Protein Synthesis Graphic Organizer
Protein synthesis is a complicated process that can be thought of as a story. In this story, there are two acts,
transcription and translation, with many characters. In this graphic organizer you are going to identify the major
characters and important events of both transcription and translation. Then you will color and label an
illustration of the entire process.
Major Characters: In the table below, identify what each molecule/enzyme does in protein synthesis.
DNA Sequence
RNA Polymerase
mRNA
tRNA
rRNA/Ribosome
Protein Synthesis Acts: Fill out the following information about the two stages of protein synthesis.
Act I: Transcription
Purpose
Location
Major Characters
What Happens
Act II: Translation
Purpose
Location
Major Characters
What Happens
Scene 1: Initiation
Scene 2: Elongation
Scene 3: Termination
Illustration
Write Transcription in the box on the left side of the image (X) and then write Translation in the box on the
right side of the image (X). Color the following important components of the protein synthesis process:
Thymine =
Adenine =
Guanine =
Cytosine =
Uracil =
the strand of DNA (D)
the strand of RNA (R)
the nuclear membrane
(E)
Ribosome (Y)
Transfer RNA (F)
Amino acids (M)
Biotechnology
Biotechnology
o Biotechnology—use and application of living things and biological processes
o Found in many fields: ___________________________________________________________
o Five major applications
Genetic Engineering
o Genetic engineering—the changing of an organism’s DNA to give an organism new traits
o Uses recombinant DNA (DNA that contains
________________________________________________________)
Created from the use of restriction enzymes and plasmids
Restriction Enzymes
o Restriction enzyme—an enzyme that cuts DNA molecules at a
_________________________________________________
o Cut different DNA in different places
o Can leave either “_____________” ends (which are straight) or “____________” ends (which
creates pieces hanging over)
Creation of Recombinant DNA
o Plasmid—closed loops of DNA that are separate from the bacterial chromosome and that
replicate on their own within the cell
o Both ______________________________ cut by restriction enzyme, leaving sticky ends
o Sticky ends connect together
Application of Genetic Engineering
o Recombinant DNA placed in bacteria ____________________________________________
(i.e. insulin, human growth hormone)
o Bacteria containing recombinant DNA infect plants, which then express new gene
Considered ______________________________
o Transgenic—an organism that has one or more genes from another organism inserted into its
genome
Bacteria & plants
o Concerns
Possible long-term side effects of eating genetically modified food
Cloning
o Clone—a __________________________________________ of a gene or of an organism
o Common in nature:
o Artificial cloning
o Benefits
Organs for transplant into humans
Save endangered species
o Concerns
Low success rate
Clones “imperfect” and less
healthy
Decreased biodiversity
PCR
o Polymerase chain reaction (PCR)—a technique that ____________________________________
of a specific DNA sequence in just hours
Models _____________________________
o Uses primers (short segment of DNA that acts as the __________________________________)
o Needs DNA polymerase, DNA sequence, nucleotides and two primers
DNA Fingerprinting
o DNA fingerprint—a representation of parts of an individual’s DNA that can be used to identify a
person at the molecular level
o DNA digested with restriction enzyme and then run on a gel
o Fragments create ___________________________________________
Gel Electrophoresis
o Gel electrophoresis—a separation technique where an ____________________________ is used
to separate a mixture of DNA fragments from each other
o Smaller fragments ________________________________________ than larger fragments
Application of DNA Fingerprinting
o Used mostly for identification
Studying biodiversity
Tracking genetically
modified crops
o Based on probability of someone have similar sequence
Often 1 in millions
Gene Sequencing & Gene Therapy
o Gene sequencing—determining the ______________________________ in genes or in genomes
o Human Genome Project
Wanted to sequence all of the nucleotides in the human genome
Wished to identify all the genes in the human genome
o Gene therapy—the replacement of a defective or missing gene, or the addition of a new gene,
into a person’s genome to treat a disease
o Uses
Genetically engineered virus to “infect” cell with gene
Insert gene to stimulate immune system to attack cancer cells
o Challenges
Assessing effect of gene on target cell
Name _____________________________________________________ Period ______
Biotechnology Summary Chart
Using your Biotechnology notes, fill out the following information in the chart to summarize all
of the biotechnology techniques:
Biotechnology
Technique Definition/Purpose Application/Usage Concerns/Challenges
Genetic Engineering
Cloning
PCR
DNA Fingerprinting
Gene
Sequencing/Gene
Therapy
Name __________________________________________________ Period ______
Who Ate the Cheese?
Introduction
DNA isolation from blood, hair, skin cells, or other genetic evidence left at the scene of a crime can be compared
with the DNA of a criminal suspect to determine guilt or innocence. This is due to the fact that every person has a
different sequence. Scientists use a small number of sequences of DNA that are known to vary among individuals, and
analyze those to get a possibility of a match. DNA is isolated, amplified through PCR, cut using restriction enzymes, and
sorted by size by gel electrophoresis. Then the DNA can be analyzed through comparing it with other samples.
In this activity, you will examine crime scene evidence to determine who is responsible for eating the Queen's
special imported Lindbergher Cheese. You will amplify the collected DNA using PCR. Then you will use gel
electrophoresis to make a DNA fingerprint of each suspect, the Queen, and the DNA collected at the crime scene. Finally
to determine whom the DNA belongs to, you will then compare the DNA fingerprints.
Incident Report
Incident Data
Incident Type: Theft Complaint Status: Pending DNA results
Processed by: Chief Wiggam Other Officers: Officer Li Gase
Property
Property Code: Rare cheese Owner's Name: Queen Elizabeth
Name: Lindbergher Value: $12,000
Burglary Data
Method of Entry: Unknown, no evidence of force on doors or windows.
Narrative: The cheese was allegedly stolen from the Queen's sitting room the night before the grand ball. The cheese was
listed as a gift from the Manchurian diplomat. Officer Li Gase dusted for fingerprints and found none on the table or
doors, the maid claimed that they had been wiped clean earlier. The wheel of cheese was on a platform in the sitting room,
and half of it had been eaten. We took pictures of the half eaten cheese and sent it to the lab for further tests. Edna N.
Zime, the lab technician said that saliva samples could be taken from the teeth imprints of the cheese that was left behind.
Suspect Data
Suspect Number 1
Name: Electra Foresis
Description of Suspicion: Electra was recently involved in a relationship with the Manchurian diplomat that sources say
ended badly. Her motive may have been to sabotage the diplomat's gift to the Queen.
Suspect Number 2
Name: Gene Tics
Description of Suspicion: Gene is the leader of the local Cheese-Makers Guild, he may not have wished for Queen
Elizabeth to have cheese from anywhere but his own guild.
Polymerase Chain Reaction (PCR)
Using the PCR simulation (http://learn.genetics.utah.edu/content/labs/pcr/), you will investigate the process
of PCR. Then answer the following questions, using information you have learned from the simulation.
1) What does PCR do?
2) Explain at least one advantage of PCR.
3) What are the ingredients needed for PCR?
4) What is the purpose of a primer?
5) What is the purpose of DNA polymerase?
6) What role does the Thermal Cycler play in PCR?
7) PCR has three steps. Describe what happens at each temperature in cycle #1:
(a) 95°C →
(b) 50°C →
(c) 72°C →
8) What happens in the Thermal Cycler moves from cycle #1 to cycle #30?
Gel Electrophoresis
In gel electrophoresis, DNA is placed in a gel and an electrical charge is applied to the gel. The positive charge is
at the top and the negative charge is at the bottom. Because DNA has a slightly negative charge, the pieces of DNA will
be attracted to the bottom. The smaller pieces move more quickly towards the bottom than the larger pieces. Using the Gel
Electrophoresis virtual lab (http://www.classzone.com/cz/books/bio_07/ book_home.htm?state=GA), you will creates a
DNA fingerprint of each DNA sample, which can be used to identify the suspect.
http://learn.genetics.utah.edu/content/labs/pcr/http://www.classzone.com/cz/books/bio_07/%20book_home.htm?state=GA
1) Draw the gel below with the different size bands labeled.
2) Using the information in the gel and in the introduction, identify the suspect and give a possible
motive.
3) Why is the largest DNA fragment band found closest to the positive end of the gel?
4) What would happen if the electrodes were plugged into the wrong outlets?
5) Why is DNA fingerprinting more conclusive when proving a person’s innocence rather than their
guilt?
Name __________________________________________________________ Period ____
From DNA to Protein Review Questions
1) Draw a nucleotide and label the three parts.
2) What are the four different nucleotides found in DNA?
3) What nucleotides pairs with T? With C?
4) Draw a DNA double helix and label the sugar-phosphate backbone, the bases, and the hydrogen bonds.
5) Explain how the DNA double helix is similar to a ladder or a spiral staircase.
6) What is DNA replication? Where does it take place?
7) When is DNA replicated during the cell cycle? Why does DNA replication need to occur?
8) Summarize the key points of DNA replication. What role does DNA polymerase play in DNA
replication?
9) If one strand of DNA has the sequence TAGGTAC, what would be the sequence of the complementary
DNA strand?
10) What must be broken for the DNA strand to separate?
11) Why is DNA replication called
semiconservative?
12) The diagram on the right shows the
central dogma:
(a) What does the diagram show?
(b) Label where the following
belong on the diagram:
translation, DNA replication,
transcription.
13) Fill in the table below to contrast
DNA and RNA:
DNA RNA
Contains the sugar deoxyribose
Has the bases A, C, G, and U
Typically double-stranded
14) Give the basic function of each type of RNA:
(a) mRNA
(b) rRNA
(c) tRNA
15) What is the purpose of transcription? Where does it take place?
16) Summarize the key points of transcription. What enzyme helps make a strand of mRNA?
17) List two ways that transcription and DNA replication are similar and two ways they are different.
18) What is the purpose of translation? Where does it take place?
19) What happens in each stage of translation: initiation, elongation, and termination?
20) What is a codon? What are the two special types of codon?
21) Give the amino acid or codon for each of the following:
(a) AGA
(b) UAG
DNA
RNA
Protein
(c) Tryptophan (Trp)
(d) Methionine (Met)
22) What is a set of three nucleotides on a tRNA molecule that is complementary to an mRNA codon?
23) For the DNA sequence (ATG CCA GTC ATC), give the mRNA strand and amino acid sequence.
24) What is the difference between an exon and an intron?
25) The diagram below represents unprocessed and processed mRNA in a eukaryotic cell.
(a) Using the diagram as a reference, fill in the legend with the corresponding element: cap, exon,
intron, and tail.
(b) Explain the difference between the unprocessed and processed mRNA.
26) What is a restriction enzyme? What is the difference between blunt ends and sticky ends?
27) What is the purpose of gel electrophoresis? How is it used with the results of restriction enzymes?
28) What is the purpose of polymerase chain reaction? What four materials are needed for PCR?
29) What is a DNA fingerprint?
30) Local police have collected evidence from a recent crime
scene and three suspects. Based on the image at the right,
identify who the suspect is and explain why.
31) What is genetic engineering?
32) What is recombinant DNA and how is it made using
restriction enzymes and plasmids?
33) What is gene therapy and how might it be used as a
treatment for cancer or for genetic disorders?
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