Interactive Notebook Table of Contents
Page
Date
Std Learning Goal
Homework
Mastery/
Effort
9/30/13
10/1/13
10/2/13
10/3/13
10/4/13
10/7/13
10/8/13
10/9/13
10/10/13
10/11/13
10/14/13
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10/15/13
10/16/13
10/17/13
10/18/13
10/21/13
10/22/13
10/23/13
10/24/13
10/25/13
10/28/13
10/29/13
10/30/13
10/31/13
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Genetics - DNA Unit 2– Overview (5 weeks)
Schedule – September 30 through October 31, 2011; Unit Exam Thursday October 31, 2013
Key Standards
The genetic composition of cells can be altered by incorporation of exogenous DNA into the cells.
Students will describe the processes of genetic engineering and biotechnology and analyze the
ethical implications. (5c, 5d) Key Elements:
1. Define the following concepts: genetic
engineering, biotechnology, ethical implication
2. Describe the processes of genetic
engineering and biotechnology.
3. Analyze the ethical implications of genetic
engineering and biotechnology.
Genes are a set of instructions encoded in the DNA
sequence of each organism that specify the sequence
of amino acids in proteins characteristic of that
organism
Students will demonstrate the role of DNA and RNA
in the processes of replication, transcription, and
translation. (1a, 4a, 4b, 4c, 5a, 5b) Key Elements:
1. Define DNA, RNA (mRNA, tRNA, rRNA),
replication, transcription, translation, genetic
code, codon, anticodon, amino acid, mutation, base
pairing, protein, complement, template.
2. Transcribe DNA into mRNA.
3. Translate mRNA into an amino acid sequence.
4. Explain the role of DNA in each of the following processes: replication, transcription, and
translation.
5. Explain the role of RNA in each of the following processes: replication, transcription, and
translation.
6. Explain the steps of each of the following processes: replication, transcription, and translation.
Textbook – Chapters 12 (pg 324 – 357) 13 (pg 358-387). Class Website –
www.marric.us/teaching;
Resources - http://www.phschool.com/science/biology_place/glossary/index.html
Tentative Schedule
9/30 – 10/4 – Chapter 12 – Chemical Structure of DNA, RNA, and Protein
10/7 - 10/11 – Chapter 12 – Transcription/Translation Process Diagrams
10/14 - 10/18 – Replication and Mutations and Processing
10/21 – 10/25 - Chapter 13 – Biotechnology – DNA Extraction Lab
10/27 - 10/31 – Review
3
Interactive Notebook Score Sheet
Quizzes/Formatives
Date
Name of Scored Assignment
Score/Max
Score
Date Due
Retake Needed
(yes or no)
Score/Max
Histogram – graphic representation of grouped data.
Peer
Initial
Peer Initials
Parent Initial
Level of Effort
Histograms are also called bar graphs. To
monitor progress we are going to track how well problems are solved on a daily basis. Each column
will represent a day (x axis) and the row progress solving problems with 5 advanced, 4 proficient, 3
basic, 2 below basis, and 1 incomplete (y axis)
4
5
The nucleus is a
membranebound
organelle that
contains the
hereditary
material in
eukaryotic
cells. This
hereditary
material is
DNA whose
information is
found in DNA’s
nitrogen bases:
adenine,
guanine,
cytosine, and
thymine. Each
DNA monomer
or subunit is a
nucleotide
which is made
of a phosphate
group, a
dexoyribose
sugar, and a
nitrogen base.
DNA is a double stranded helix (ladder) and is complementary in that one strands thymine (T) pairs
with the other strands adenine (A). Likewise cytosine (C) pairs with guanine (G) in accordance
with Chargaff’s Rule.
6
DNA is transcribed (transcription) as messenger RNA that is transferred from the nucleus to the
cytoplasm by exiting the nuclear pores. DNA needs messenger RNA because DNA is double
stranded and cannot exit the nuclear pores whereas RNA is single stranded and can do so.
RNA is made from DNA by an enzyme called RNA polymerase (an enzyme that makes a polymer of
RNA). Additionally RNA (made of ribose sugar) does not have a thymine base instead RNA has the
base uracil (U) which pairs with adenine (A). The hereditary information must get into the
cytoplasm where ribosomes are located because ribosomes are the structures where messenger
RNA is translated (translation) into a protein (polypeptide with the help of transfer RNA (tRNA).
Ribosomes along with tRNA translate the genetic information into a protein by adding one amino
acid per three mRNA bases (codons). Both prokaryotic and eukaryotic cells have ribosomes and
tRNA to make proteins –remember viruses do not have ribosomes and cannot make their own
proteins.
DNA must also replicate itself when a new cell is needed. The process involves several other
enzymes including DNA helicase (opens the helix), DNA polymerase, RNA primase, and DNA ligase.
With so many steps and enzymes involved it is a miracle that there are so few errors in the
replication process.
Especially when you consider that a human genome has about 30,000 genes and 3.5 billion base
pairs. Nevertheless, mutations do occur: insertions, deletions, substitutions as point mutations or
frameshift mutations (insertion or deletion mutations) which can affect the type of protein that is
produced. Besides having great repair enzymes the code has a redundancy that helps maintain
integrity in that there are multiple codons that code for the same amino acid: 20 amino acids per
64 possible base combinations in a codon (4x4x4). When a mutation does occur the three most
common outcomes are cancer, birth defects, or no problem at all. The regulation of gene
expression is very complicated and most is known about prokaryote (bacteria) gene regulation. You
will learn about two operons or regulatory units called the trp operon and the lac operon. Onward
molecular biologists.
7
1. Adenine_________________________________________________________________
2. Amino acid_______________________________________________________________
3. Anticodon________________________________________________________________
4. Base pairing _____________________________________________________________
5. Birth defect_____________________________________________________________
6. Cancer__________________________________________________________________
7. Chromosome______________________________________________________________
8. Codon___________________________________________________________________
9. Complementary strand ______________________________________________________
10. Cytosine_________________________________________________________________
11. Deletion mutation _________________________________________________________
12. Deoxyribose _____________________________________________________________
13. Double helix _____________________________________________________________
14. Enzyme _________________________________________________________________
15. Expressed gene ___________________________________________________________
16. Exon ___________________________________________________________________
17. Frameshift mutation________________________________________________________
18. Gene ___________________________________________________________________
19. Genetic code _____________________________________________________________
20. Genome _________________________________________________________________
21. Genotype ________________________________________________________________
22. Guanine _________________________________________________________________
23. Hemoglobin______________________________________________________________
24. Heredity ________________________________________________________________
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25. Heterozygous_____________________________________________________________
26. Homozygous _____________________________________________________________
27. Intron __________________________________________________________________
28. Insertion mutation _________________________________________________________
29. Inversion mutation _________________________________________________________
30. Ligase __________________________________________________________________
31. Mutation(s) _____________________________________________________________
32. Nitrogen bases____________________________________________________________
33. Nucleotide ______________________________________________________________
34. Okasaki Fragment__________________________________________________________
35. Plasmid__________________________________________________________________
36. Phosphate group___________________________________________________________
37. Polymerase_______________________________________________________________
38. Probability_______________________________________________________________
39. Promoter ________________________________________________________________
40. Protein__________________________________________________________________
41. Purine __________________________________________________________________
42. Pyrimidine _______________________________________________________________
43. Recessive________________________________________________________________
44. Regulatory site ___________________________________________________________
45. Replication ______________________________________________________________
46. Repressor _______________________________________________________________
47. Ribose _________________________________________________________________
48. Template ________________________________________________________________
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49. Thymine ________________________________________________________________
50. Trait __________________________________________________________________
51. Transcription ____________________________________________________________
52. Translation (protein synthesis) _______________________________________________
53. Translocation ____________________________________________________________
54. tryptophan ______________________________________________________________
55. Uracil __________________________________________________________________
56. DNA __________________________________________________________________
57. RNA ___________________________________________________________________
58. tRNA (transfer RNA) ______________________________________________________
59. mRNA (messenger RNA) ____________________________________________________
60. rRNA (ribosomal RNA) ______________________________________________________
61. Biotechnology_____________________________________________________________
62. Clone ___________________________________________________________________
63. Genetic engineering _______________________________________________________
64. Variation ________________________________________________________________
65. 3’ (three-prime) ___________________________________________________________
66. 5’ (five-prime) ____________________________________________________________
67. Catalyzing_______________________________________________________________
68. Tay-Sacs________________________________________________________________
69. Sickle-Cell Anemia_________________________________________________________
70. Cistic Fibrosis____________________________________________________________
71. Muscular Dystrophy________________________________________________________
10
Unit 2 Genetics – DNA
1. What are the building blocks of DNA?
Name:______________________________
Date:________________ Period:________
2. Arrange the following in order from largest to smallest in size?
Nucleus, DNA, Chromosome, nucleotide, cell
3. What are the purine bases and what are the pyrimidine bases for DNA:
a) Purine bases =
b) Pyrimidine bases =
4. A particular sequence of parent DNA has four purine bases and two pyrimidine bases.
According to base-pairing rules what are the possible sequences formed during replication:
Represent Purine as Pu and Pyrimidine as Py
5. In which part of the cell does this process shown above take place?
6. Structure I in the figure above represents a(n) __________________________________.
7. Structure II in the figure above represents a(n) _________________________________.
8. Structure III in the figure above represents a(n) ________________________________.
9. Structure IV in the figure above represents a(n) _________________________________.
10. Structure IV in the figure above represents a(n)__________________________________.
11. The process illustrated in the figure above is called _______________________________.
12. Which of the structures in the figure above are composed of RNA?
11
13. X-ray evidence was used to discover that the shape of DNA was a
14. In 1962 a Nobel Prize for Medicine/Physiology was awarded to whom?
_______
.
15. The information that directs replication, transcription and translation is found in DNA’s
___________________
16. What is Chargaff’s Rule and how was it important for determining DNA’s structure?
17. This segment of DNA has undergone a mutation in
which six nucleotides have been deleted. A repair enzyme
would replace them. Which series of bases will complete
the strand of DNA?
The messenger RNA codes for six different amino acids are shown in the table below.
18. In one type of mutated gene for hemoglobin, CAC has
replaced the normal CTC in the DNA code. What amino
acid substitution has taken place in the mutated
hemoglobin?
19. Process 1 in the diagram above is known as
20. Process 2 in the diagram above is known as
21. Process 3 in the diagram above is known as
22. What is the product of process 3 as shown in the diagram above,?
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______
23. Which process in the diagram above occurs in the
nucleus?____________________________
24. Which process in the diagram above occurs in the cytoplasm? _________________________
25. How many bases are needed to specify four amino acids?
26. What is the difference between the lagging strand and the leading strand?
27. A DNA segment is changed from-AAGTAG- to -AAATAG-. This is a
________________mutation.
28. A DNA segment is changed from -AATTAGAAATAG- to -ATTAGAAATAG-. This is a(n)
__________________________ mutation.
29. Here are two related mRNA sequences: 5'UUUAGCGAGCAU3' and
5'UUUAGCCAUAAAAAAAA3'. How was the second sequence formed?
30. Use the amino acid code chart to sequence the following messenger RNA strand into an amino
acid strand.
a. AUG
b. UUA
c. CCC
d. CAA
e. UUU
f.
f. What are the 3 stop codons
13
Help Wanted
Positions Available in the genetics industry. Hundreds of entry-level openings for
tireless workers. No previous experience necessary. Must be able to transcribe
code in a nuclear environment.
Accuracy and Speed vital for this job in the field of translation. Applicants must
demonstrate skills in transporting and positioning amino acids. Salary
commensurate with experience.
Executive Position available. Must be able to maintain genetic continuity through
replication and control cellular activity by regulation of enzyme production.
Limited number of openings. All benefits.
Supervisor of production of proteins—all shifts. Must be able to follow exact
directions from double-stranded template. Travel from nucleus to the cytoplasm
is additional job benefit.
31. Applicants for the first job of the Help Wanted ad in the table above "Position Available,"
could qualify if they were ______________________________.
32. Applicants for the second job of the Help Wanted ad in the table above "Accuracy and Speed
vital," could qualify if they were ______________________________.
33. Applicants for the third job of the Help Wanted ad in table above "Executive Position," could
qualify if they were _________________________.
34. Applicants for the fourth job of the Help Wanted ad in the table above "Supervisor," could
qualify if they were ______________________________.
35. What is the mRNA sequence for a strand of DNA reading CACGTAC?
36. The template strand of a piece of DNA being replicated reads: 5'-ATAGGCCGT-3'. A partially
synthesized Okazaki fragment is 5'CCTA3'. If the next fragment is four bases long, what is
its first base?
37. What type of mutation has occurred in
the figure?
38. What will be the result of the mutation in
the figure above?
14
39. This is a template DNA sequence: 3' AATCGCA 5'. This is a partially-completed mRNA strand
transcribed from the DNA template: 3'GCGA5'. What is the next nucleotide that RNA
polymerase will attach?
40. Using DNA sequencing, you discover that a bacterium has experienced a deletion mutation that
removed three nucleotides. The bacterium appears completely unaffected in all its functions.
Where is the mostly likely location for the mutation?
41. Three samples of DNA contain the
percentages of nitrogenous bases listed in
Table 12-2. According to Chargaff’s law,
which two samples probably belong to the
same species? Explain why.
42. You have a building toy set consisting of parts that can be connected together. You are
going to use it to model a piece of DNA. You have decided that each part of DNA will be
represented by a different type of toy piece. You have chosen the following four pieces so
far: adenine = large red cube; guanine = large green cube, thymine = small orange cube;
cytosine = small blue cube. How many other types of pieces do you need to represent the
remaining parts both the 3-prime and the 5-prime strands of a section of DNA?
43. Describe the parts which are found in each nucleotide found in DNA?
a. ____________________________________________________________
b. ____________________________________________________________
c. ____________________________________________________________
44. Because of base pairing in DNA, the percentage of ______________________ in DNA is
about equal to the percentage of _________________________.
45.
DNA is copied during a process called ________________________
46.
How is RNA different from DNA?
15
47.
Which type(s) of RNA is(are) involved in protein synthesis?
48. What is produced during transcription?
49. During transcription, an RNA molecule is formed:
a. Inside the ____________________
b. Is _____________-stranded
c. Is ___________________ to one of the strands of DNA
50. Why is it possible for an amino acid to be specified by more than one kind of codon?
51. Which type of RNA functions as a blueprint of the genetic code?
52. What happens during the process of translation?
53. The cell uses information from messenger RNA to produce _____________.
54. During translation, the type of amino acid that is added to the growing polypeptide depends
on the ___________________on the mRNA and the _________________ on the tRNA
to which the amino acid is attached.
55. Explain the following types of gene mutations:
a. Insertion b. Deletion c. Substitution d. Point mutation –
e. Frame-shift mutation 56. What is a promoter?
57. RNA polymerase is used to ________________________________________________.
58. An expressed gene is turned ___________.
59. Proteins that bind to ____________________________ on DNA determine whether a
gene is expressed.
60. If a specific kind of protein is not continually used by a cell, the gene for that protein is
______________________________________
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61. A bacterium that was once able survive in a tryptophan-free environment is now unable to
synthesize its own tryptophan. The bacterium is otherwise unaffected. Where is the most
likely location for the mutation causing the change?
62. What can result when a mutation to DNA occurs?
63. Under certain conditions RNA can perform additional functions which include?
64. Describe the following enzymes:
a. DNA helicase –
b. DNA ligase –
c. DNA polymerase d. RNA primase e. RNA polymerase 65. What are introns and exons?
66. Compare and contrast the trp operon and the lac operon
67. What are plasmids and how are they used in biotechnology
17
DNA - The Double Helix
Recall that the nucleus is a small spherical, dense body in a cell. It is often called the "control center" because it controls all the
activities of the cell including cell reproduction, and heredity. Chromosomes are microscopic, threadlike strands composed of
the chemical DNA (short for deoxyribonucleic acid) and proteins (histones). This DNA is called chromosomes when the DNA
molecule is condensed (moving during mitosis or meiosis) or chromatin when the DNA is relaxed (working). In simple terms,
DNA controls the production of proteins within the cell. These proteins in turn, form the structural units of cells and control all
chemical processes within the cell. Think of proteins as the building blocks for an organism, proteins make up your skin, your
hair, parts of individual cells. How you look is largely determined by the proteins that are made. The proteins that are made are
determined by the sequence of DNA in the nucleus.
Chromosomes are composed of genes, which is a segment of DNA that codes for a particular protein which in turn codes for a
trait. Hence you hear it commonly referred to as the gene for baldness or the gene for blue eyes. Meanwhile, DNA is the
chemical that genes and chromosomes are made of. DNA is called a nucleic acid because it was first found in the nucleus. We
now know that DNA is also found in organelles, the mitochondria and chloroplasts, though it is the DNA in the nucleus that
actually controls the cell's workings.
In 1953, James Watson and Francis Crick established the structure of DNA. The shape of DNA is a double helix (color the title
black), which is like a twisted ladder. The sides of the ladder are made of alternating sugar and phosphate molecules. The
sugar is deoxyribose. Color all the phosphates pink (one is labeled with a "p"). Color all the deoxyriboses blue (one is labeled
with a "D").
The rungs of the ladder are pairs of 4 types of nitrogen bases. The bases are known by their coded letters A, G, T, C. These
bases always bond in a certain way. Adenine will only bond to thymine. Guanine will only bond with cytosine. This is known as
the "Base-Pair Rule". The bases can occur in any order along a strand of DNA. The order of these bases is the code that
contains the instructions. For instance ATGCACATA would code for a different gene than AATTACGGA. A strand of DNA
contains millions of bases. (For simplicity, the image only contains a few.)
Color the thymines orange.
Color the guanines purple.
Color the adenines green.
Color the cytosines yellow.
Note that that the bases attach to the sides of the ladder at the sugars and not the phosphate.
The DNA helix is actually made of repeating units called nucleotides. Each nucleotide consists of three molecules: a sugar
(deoxyribose), a phosphate which links the sugars together, and then one of the four bases. Two of the bases are purines adenine and guanine. The pyrimidines are thymine and cytosine. Note that the pyrimidines are single ringed and the purines
are double ringed. Color the nucleotides using the same colors as you colored them in the double helix.
The two sides of the DNA ladder are held together loosely by hydrogen bonds. The DNA can actually "unzip" when it needs to
replicate - or make a copy of itself as it does during interphase in a cell’s life cycle prior to mitosis. DNA needs to copy itself
when a cell divides, so that the new cells each contain an exact copy of the DNA. Without these instructions, the new cells
wouldn't have the correct information. When an alteration occurs uncontrolled cell growth can occur as does in cancerous cells.
The hydrogen bonds are represented by small circles. Color the hydrogen bonds grey.
Messenger RNA
So, now, we know the nucleus controls the cell's activities through the chemical DNA, but how? It is the sequence of bases that
determine which protein is to be made. The sequence is like a code that we can now interpret. The sequence determines
which proteins are made and the proteins determine which activities will be performed. And that is how the nucleus is the
control center of the cell. The only problem is that the DNA is too big to go through the nuclear pores in the nuclear membrane.
So a chemical is used to read the DNA in the nucleus. That chemical is messenger RNA. The messenger RNA (mRNA) is
small enough to go through the nuclear pores. It takes the "message" of the DNA to the ribosomes and "tells them" what
proteins are to be made. Recall that proteins are the body's building blocks. Imagine that the code taken to the ribosomes is
telling the ribosome what is needed - like a recipe. Messenger RNA is similar to DNA, except that it is a single strand, and it
has no thymine. Instead of thymine, mRNA contains the base Uracil. In addition to that difference, mRNA has the sugar ribose
instead of deoxyribose. RNA stands for Ribonucleic Acid. Color the mRNA as you did the DNA, except:Color the
ribose a DARKER BLUE, and the uracil brown.
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The Blueprint of Life
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? Although much work remains in genetics, it has become apparent that a cell
has the ability to turn off most genes and only work with the genes necessary to do a job. We also know that a lot of DNA
apparently is nonsense and codes for nothing. These regions of DNA that do not code for proteins are called "introns",
sometimes "junk DNA", or “intervening sequence” and these regions remain in the nucleus. The sections of DNA that do
actually code from proteins are called "exons" and these become part of the final RNA that exits the nucleus.
1. Write out the full name for DNA. _____________________________________________
2. What is a gene? _______________________________________________________
3. Where in the cell are chromosomes located? _______________________________________________________
4. DNA can be found in what two organelles? _________________________________________________________
5. What two scientists established the structure of DNA? ______________________________________________
6. What is the shape of DNA? ______________________________________
7. What are the sides of the DNA ladder made of? ________________________________________
8. What are the "rungs" of the DNA ladder made of? _______________________________________________________
9. What sugar is found in DNA? _______________________ In RNA? ____________________
10. How do the bases bond together? A bonds with _____
G bonds with _______
11. The two purines in DNA are ______________________________________________________.
12. DNA is made of repeating units called _______________________________________________________
13. Why is RNA necessary to act as a messenger? Why can't the code be taken directly from the DNA?
14. Proteins are made where in the cell?
15. How do some cells become brain cells and others become skin cells, when the DNA in ALL the cells is exactly the same. In
other words, if the instructions are exactly the same, how does one cell become a brain cell and another a skin cell?
16. Why is DNA called the "Blueprint of Life"?
19
DNA Double Helix
20
DNA/RNA Structure Standards
5a. Students know the chemical structure of DNA, RNA, and protein.
1. Students know that all cells contain the molecule DNA which stores and transfers genetic information.
Prokaryotes store DNA in the _____________
Eukaryotes store DNA in the ____________
2. Students can describe the structure of DNA as a double
stranded molecule consisting of nucleotides. The backbone of
the DNA molecule consists of “sugar phosphate” units while the
“rungs” consist of nitrogen-containing bases. [A, G, C, & T].
We Love DNA (to the tune of “Row,
Row, Row Your Boat”)!
We love DNA
Made of nucleotides.
Sugar, phosphate and a base
Bonded down one side.
Adenine and thymine
Make a lovely pair.
Cytosine without guanine
Would feel very bare.
3. Students can describe the structure of
RNA as a single-stranded molecule
consisting of the same A, G, and C
nucleotides but with Uracil instead of
Thymine.
4. Students can identify the two different
types of RNA [mRNA and tRNA] and
describe their functions.
Nucleic acids are polymers composed of monomers called nucleotides. Each nucleotide consists of three
subunits: a five-carbon pentose sugar, a phosphoric acid group, and one of four nitrogen bases. (For DNA
these nitrogen bases are adenine, guanine, cytosine, or thymine.) DNA and RNA differ in a number of major
21
ways. A DNA nucleotide contains a deoxyribose sugar, but RNA contains ribose sugar. The nitrogen bases in
RNA are the same as those in DNA except that thymine is replaced by uracil. RNA consists of only one
strand of nucleotides instead of two as in DNA. The DNA molecule consists of two strands twisted around
each other into a double helix resembling a ladder twisted around its long axis. The outside, or uprights, of
the ladder are formed by the two sugar-phosphate backbones. The rungs of the ladder are composed of pairs
of nitrogen bases, one extending from each upright. In DNA these nitrogen bases always pair so that T pairs
with A, and G pairs with C. This pairing is the reason DNA acts as a template for its own replication. The
bonds between the nitrogen bases are hydrogen bonds which are relatively weak allowing DNA to be
separated for replication and transcription. RNA exists in many structural forms, many of which play different
roles in protein synthesis. The mRNA form serves as a template during protein synthesis, and its codons are
recognized by aminoacylated tRNAs. Protein and rRNA make up the structure of the ribosome.
DNA
vs
RNA
Proteins are polymers composed of amino acid monomers. Different types of proteins function as enzymes,
transport molecules, hormones, structural components of cells, and antibodies that fight infection. Most cells
in an individual organism carry the same set of DNA instructions but do not use the entire DNA set all the
time. Only a small amount of the DNA appropriate to the function of that cell is expressed. Genes are,
therefore, turned on or turned off as needed by the cell (regulated), and the products coded by these genes are
produced only when required.
22
The base________________ pairs with _____________. The base ___________ Pairs with __________.
This is called complementary base pairs. Thus one strand of the DNA is complementary to the other strand
(opposite/matching). 5’-----3’ 3’-----5’
_____________________
The structure of DNA resembles a twisted ladder.
Which part of the nucleotide is found comprising the “rungs” of the ladder?
Which part of the nucleotide is found comprising the “frame” of the ladder?
The molecule transcribed/coded directly from DNA is represented by number __ and is called
____________________
The ____________________ can leave the _______________ through the ________________and enter the
___________________ because the molecule is _______________________ not _____________________.
Structure 2 is called a _____________ or _________________ because it carries an amino acid and can help
___________________ the genetic code. because it consists of three nucleotides. The structure 2 recognizes
a __________________ because it has a complementary _________________.
Structure 3 is the building blocks of _________________.
Structure 4 is the __________________ which holds the messenger RNA so that translation using the transfer
RNA can occur.
The bond labeled 5, formed between two amino acids, is known as a __________________________
Which of the following units are repeatedly joined together to form a strand of DNA?
1. amino acids
3. nucleotides
2. fatty acids
4. polysaccharides
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The weakest bonds in a double-stranded molecule of deoxyribonucleic acid exist between the______________
(1) deoxyribose sugars
(2) phosphate groups
(3) nitrogenous bases (4) 5-carbon sugars
Molecules C, D, and E will combine to form part of
_______________________________
1. DNA
2. RNA
3. a polysaccharide
4. a polypeptide
Structure B represents a molecule of
____________________________________
1. nuclear DNA
2. cytoplasmic DNA
3. ribosomal RNA
4. transfer RNA
How many codons are located on the messenger
RNA molecule in the diagram?
The type of molecule represented at A is synthesized
according to a template found in
1. DNA
2. RNA
3. dipeptides
4. amino acids
The process shown here would occur in the _____________________ of a cell
One similarity between DNA and messenger RNA molecules is that they both contain
1. the same sugar
2. genetic codes based on sequences of bases
3. a nitrogenous base known as uracil
4. double-stranded polymers
Which of the following features of DNA is most important in determining the phenotype of an organism?
1. the direction of the helical twist
2. the number of deoxyribose sugars
3. the sequence of nitrogenous bases
4. the strength of the hydrogen bonds
A portion of one strand of a DNA molecule has the sequence shown : ACCTGAAGG
Assuming there are no mutations in this portion of the DNA, what is the corresponding sequence on the
complementary DNA strand?
1. ACCTGAAGG
2. GTTCAGGAA
3. TGGACTTCC
4. UGGACUUCC
24
25
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. Also the sugar in RNA is different from DNA.
Ribose is the RNA sugar while deoxyribose is the sugar in DNA
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
Guanine = purple
Adenine = dark green
Cytosine = yellow
Uracil = brown
Color the strand of DNA light blue (D) and the strand of mRNA dark blue (R). Color the nuclear membrane (E)
black.
Translation
Translation occurs in the cytoplasm, specifically on the ribosomes. The mRNA made in the nucleus travels out of
the nucleus through nuclear pores into the cytoplasm and the ribosome so that the "message" of the DNA can be
carried out. Here at the ribosome, the message will be translated into an amino acid sequence. Color the ribosome
light green (Y) and note how the mRNA strand threads through the ribosome like a tape measure and the amino
acids are assembled. The mRNA strand in the translation area should also be colored light blue, as it was colored
in the nucleus.
Label the box with the X that is located in the cytoplasm with the word TRANSLATION.
Important to the process of translation is another type of RNA called Transfer RNA (F) which functions to carry the
amino acids to the site of protein synthesis on the ribosome. Color the tRNA red.
A tRNA has two important areas. 1) The anticodon, which matches the codon on the mRNA strand and 2) the
amino acid located on top of the tRNA. 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 mRNA strand they are the same molecules!
At the top of the tRNA is the amino acid. 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 like box cars on a train. Color all the amino acids (M) pink.
Questions:
1. How many different kinds of bases can be found on DNA _____
2. What base is found on RNA but not on DNA? _____________
3. How many bases are in a codon? ______ In an anticodon? ____________
4. How many amino acids are attached to a single transfer RNA? _______
5. Transcription occurs in the _________; translation occurs in the ____________.
6. The process of making RNA from DNA is called ___________________ and it occurs in the
___________________
7. The process of assembling a protein from RNA is called _________________ and it occurs in the
_______________
8. What will the last amino acid added to the protein in the picture? __________________________________
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DNA Structure Review
1. The structure of DNA is made up subunits shown on the diagram by an X.
This subunit is called a ________________.
2. The rings labeled A, T, G, and C represent ______________________.
3. The pentagon shaped structures in the molecule are sugars which in DNA
are ______________.
4. The shape of DNA is described as a ______________________________.
5. Before a cell goes through either mitosis (an identical cell formed) or meiosis (a gamete cell
such as an egg or sperm formed) the process of ____________________ must be carried out
by the DNA in the nucleus.
6. There are two types of nitrogen bases purines (double-ringed) such as ________________
and pyrimidines (single-ringed) such as ______________________. In 1950, Erwin Chargaff
and colleagues examined the chemical composition of DNA and demonstrated that the amount
of adenine always equals that of thymine, and the amount of guanine always equals that of
cytosine. This observation became known as Chargaff's rule. Therefore because of these basepairing relationships the amount of ________________ is equal to the amount of
____________________ in DNA. Describe the base-pairing rules that are used to form
complementary strands of DNA
7. A segment of a DNA strand has the following bases: 5’ TAC GAT 3’. What is the complementary
strand of DNA?
8. During DNA replication, a DNA strand that has the bases 3’ CTAGGT 5’ produces a strand with
the bases:
9. The three basic steps for DNA replication are listed below. Write the name of enzyme
responsible for each step
a.
Unwinding -
b. Adding nucleotides complementary to a parent strand –
c. Attaching fragments together 10. DNA replication is called semi-conservative because the new strands that are produced consist
of one ________ strand and one __________ strand. The strand that is leading strand is
replicated ___________________. The complementary strand requires RNA primers to
provide a 5’ end and produces fragments called _________________ fragments.
11. DNA replication occurs in the ____________________, another process that occurs in the
nucleus is ___________________ which produces _______________________ that leaves
the nucleus and enters the ________________. The final step of the central dogma is the
production of proteins that involve specific amino acid carrying delivery trucks
_______________ that bind to ribosomes – protein factories based on a ________ sequence.
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Replication
2. What is the difference between the lagging strand and the leading strand?
Describe the function of the following enzymes involved in replication
3. DNA helicase –
4. DNA ligase –
5. DNA polymerase –
6. RNA primase –
7. The template strand of a piece of DNA being replicated reads: 5'-ATAGGCCGT-3'. A partially
synthesized Okazaki fragment is 5'CCTA3'. If the next fragment is four bases long, what is
its first base?
DNA Repair
8. This segment of DNA has undergone a mutation in which
six nucleotides have been deleted. A repair enzyme would
replace them. Which series of bases will complete the
strand of DNA?
9. A particular sequence of parent DNA has five purine bases and two pyrimidine bases. According
to base-pairing rules, which of the following sequences could be formed during replication?
a.
two cytosine, three adenine, two thymine
b.
two cytosine, three adenine, two uracil
c.
three adenine, two thymine, one guanine, one cytosine
d.
three adenine, two guanine, two cytosine
10. Explain how replication occurs, include enzymes involved and describe the semi-conservative
nature of DNA replication.
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Translation
1. In which part of the cell does this process shown above take place?
2. Structure I in the figure above represents a(n) _______________________________
3. Structure II in the figure above represents a(n) ______________________________
4. Structure III in the figure above represents a(n) _____________________________
5. Structure IV in the figure above represents a(n) ______________________________
6.
Structure IV in the figure above represents a(n) ______________________________
7. What is translation?
8. Which of the structures in the figure above are composed of RNA?
The messenger RNA codes for six different amino acids are shown in the table below.
MESSENGER RNA CODONS FOR AMINO ACIDS
Amino Acid
Messenger RNA Codons
Arginine
CGU, CGC, CGA, CGG
Cysteine
UGU, UGC
Glutamic acid
GAA, GAG
Leucine
CUU, CUC, CUA, CUG
Serine
AGU, AGC
Valine
GUU, GUC, GUA, GUG
9. In one type of mutated gene for hemoglobin, CAC
has replaced the normal CTC in the DNA code. What
amino acid substitution has taken place in the mutated
hemoglobin?
10. Why is it possible for an amino acid to be specified by more than one kind of codon?
11. The cell uses information from messenger RNA to produce _______________.
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12. During translation, the type of amino acid that is added to the growing polypeptide depends on
the _____________on the mRNA and the _____________ on the tRNA to which the
amino acid is attached.
Translate the following messenger RNA sequences
13. UAC CGU GGA
14. CGC ACA GCA
15. CCA ACC AGA
16. AUG GCC UAC
17. GGU CUA GUU
18. UAG AUG CCC
19. CCG CAU UGG
20. GAC AAU UCG
21. AUG UUU UAA
22. Which of the following would be least likely to happen as a result of a mutation in a person's
skin cells?
a. skin cancer
b. reduced functioning of the skin cell
c. no change in functioning of the skin cell
d. the person's offspring have mutated skin
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