Download File - Mrs. Badger`s Honors Biology Class

Name ______________________________ Class ___________________ Date __________________
From DNA to Proteins
Study Guide B
Answer Key
7. The sugar-phosphate backbone is like the
twisting handrails of the staircase, and the
nitrogen-containing bases are like the steps
that connect the railings to each other.
8. Because A only pairs with T and C only
pairs with G, the amount of A will be equal
to the amount of T, and the amount of C will
be equal to the amount of G.
SECTION 1. STRUCTURE OF DNA
1.
2.
3.
4.
5.
6.
Nucleotide: Refer to the Visual Vocab in
Section 2 for visual answers. Students
should label: phosphate group; nitrogencontaining base; and deoxyribose sugar.
4
the phosphate group and the deoxyribose
sugar; the nitrogen-containing base
that it was of uniform width
by building models
The sugar-phosphate backbone is on the
outside. Inside the structure, a base with two
rings always pairs with a base with only one
ring.
A; G
DNA Double Helix: drawing should include
sugar-phosphate backbone; nitrogencontaining bases; and hydrogen bonds
SECTION 2. DNA REPLICATION
1. the process by which DNA is copied during
the cell cycle
2. nucleus
3. S stage
4. so that every cell will have a complete set of
DNA following cell division
5. something that serves as a pattern
6. ATCCATG
7. Proteins help unzip the DNA strand, hold
the strands apart, and bond nucleotides
together.
8. hydrogen bonds connecting base pairs
9. because each molecule consists of one old
strand and one new strand
10. Enzymes unzip the helix.
11. DNA polymerase binds nucleotides together
to form new strands that are complementary
to the original strands.
12. Two identical DNA molecules result.
13. DNA polymerase is an enzyme that makes
DNA by forming bonds between
nucleotides. The “-ase” ending signals that it
is an enzyme. The first part of the word tells
that the enzyme makes DNA by stringing
together lots of monomers to form polymers.
14. Replication is the process by which DNA is
copied during the cell cycle. Accept any
reasonable answer. Students may compare
replication to making copies on a copier.
15. Share the best bumper stickers with the
class.
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
i
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Study Guide B continued
SECTION 3. TRANSCRIPTION
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
SECTION 4. TRANSLATION
replication (nucleus)
transcription (nucleus)
translation (cytoplasm)
Contains the sugar ribose
Has the bases A, C, G, and T
Typically single-stranded
RNA polymerase
A large transcription complex, including
RNA polymerase and other proteins,
assembles at the start of a gene and begins to
unwind the DNA. Using one strand of the
DNA as a template, RNA polymerase
strings together a complementary strand of
RNA. The RNA strand detaches from the
DNA as it is transcribed, and the DNA zips
back together.
mRNA: intermediate message that is
translated to form a protein; rRNA: forms
part of ribosomes; tRNA: brings amino
acids from the cytoplasm to a ribosome to
help make the growing protein
Both occur within the nucleus of eukaryotic
cells, are catalyzed by large enzymes,
involve unwinding of the DNA double helix,
involve complementary base pairing of the
DNA strand, and are highly regulated by
the cell.
Replication occurs only once during each
round of the cell cycle and makes a doublestranded copy of all the DNA in a cell.
Transcription occurs repeatedly throughout
the cell cycle to make proteins, rRNAs, and
tRNAs as needed by a cell. Transcription
makes a single-stranded complement of only
a particular DNA sequence.
mRNA is a form of the DNA message that
tells the cell what type of protein to make.
rRNA is a key component of ribosomes.
tRNA transfers, or carries, amino acids from
the cytoplasm to the ribosome.
the process of copying a sequence of DNA
to produce a complementary strand of RNA
1. the process that converts an mRNA message
into a polypeptide, or protein
2. sequences of three nucleotides that code for
an amino acid
3. RNA
4. the order in which nucleotides are read; they
are read as a series of three, nonoverlapping
nucleotides
5. arginine (Arg)
6. stop codon
7. UGG
8. glycine (Gly)
9. Ribosomes, tRNA molecules
10. amino acid, anticodon
Cycle Diagram:
A. An exposed codon attracts a
complementary tRNA bearing an amino
acid.
B. the ribosome forms a peptide bond
between the amino acids. It breaks the bond
between the first amino acid and tRNA.
C. the ribosome pulls the mRNA strand the
length of one codon. The first tRNA exits
the ribosome, and another codon is exposed.
11. codons
12. anticodon
13. Stop codons indicate where translation is to
stop. (Students may mention that methionine
is also a start codon.)
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
ii
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
SECTION 5. GENE EXPRESSION AND
REGULATION
SECTION 6. MUTATIONS
1. point mutation/substitution; frameshift
mutation
2. gene duplication; translocation
3. chromosomal mutation
4. chromosomal mutation
5. the attachment of a piece of one
chromosome to a nonhomologous
chromosome
6. Answers will vary.
7. Answers will vary.
8. noncoding regions
9. premature stop codon
10. no change
11. lack of regulation
12. altered splice site
13. germ cells/gametes
14. no
15. an agent in the environment that can change
DNA
16. UV light can cause neighboring thymine
nucleotides to break their hydrogen bonds to
adenine and bond with each other instead.
17. a change in an organism’s DNA
18. a frameshift mutation
Diagram legend: exon; intron
1. An exon is a sequence of nucleotides that is
expressed in a protein, whereas an intron is
an intervening sequence of nucleotides that
will be removed during processing.
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
3
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Section 1: Structure of DNA
Study Guide B
KEY CONCEPT
DNA structure is the same in all organisms.
VOCABULARY
nucleotide
base pairing rules
double helix
MAIN IDEA: DNA is composed of four types of nucleotides.
In the space below, draw a nucleotide and label its three parts using words and
arrows.
1. How many types of nucleotides are present in DNA?
_______________________________________________________________
2. Which parts are the same in all nucleotides? Which part is different?
_______________________________________________________________
_______________________________________________________________
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
4
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Study Guide B continued
MAIN IDEA: Watson and Crick developed an accurate model of DNA’s threedimensional structure.
3. What did Franklin’s data reveal about the structure of DNA?
_______________________________________________________________
4. How did Watson and Crick determine the three-dimensional shape of DNA?
_______________________________________________________________
5. How does DNA base pairing result in a molecule that has a uniform width?
_______________________________________________________________
MAIN IDEA: Nucleotides always pair in the same way.
6. What nucleotide pairs with T? with C?
_______________________________________________________________
In the space below, draw a DNA double helix. Label the sugar-phosphate
backbone, the nitrogen-containing bases, and the hydrogen bonds.
Vocabulary Check
7. Explain how the DNA double helix is similar to a spiral staircase.
_______________________________________________________________
_______________________________________________________________
8. How do the base pairing rules relate to Chargaff ’s rules?
_______________________________________________________________
_______________________________________________________________
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
5
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Section 2: DNA Replication
Study Guide B
KEY CONCEPT
DNA replication copies the genetic information of a cell.
VOCABULARY
replication
DNA polymerase
MAIN IDEA: Replication copies the genetic information.
1. What is DNA replication?
_______________________________________________________________
2. Where does DNA replication take place in a eukaryotic cell?
_______________________________________________________________
3. When is DNA replicated during the cell cycle?
_______________________________________________________________
4. Why does DNA replication need to occur?
_______________________________________________________________
5. What is a template?
_______________________________________________________________
6. If one strand of DNA had the sequence TAGGTAC, what would be the
sequence of the complementary DNA strand?
_______________________________________________________________
MAIN IDEA: Proteins carry out the process of replication.
7. What roles do proteins play in DNA replication?
_______________________________________________________________
8. What must be broken for the DNA strand to separate?
_______________________________________________________________
9. Why is DNA replication called semiconservative?
_______________________________________________________________
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
6
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Study Guide B continued
Use words and diagrams to summarize the steps of replication, in order, in the
boxes below.
10.
_______________
_______________
11.
12.
_______________
_______________
_______________
_______________
MAIN IDEA: REPLICATION IS FAST AND ACCURATE.
Vocabulary Check
13. Explain what DNA polymerase is by breaking the word into its parts.
_______________________________________________________________
14. Write a short analogy to explain what replication is.
_______________________________________________________________
Be Creative
15. People sometimes like to display bumper stickers that relate to their trade or
field of study. For example, a chemist may have a bumper sticker that says “It
takes alkynes to make the world.” Then, chemists or other people who know
that an alkyne is a molecule that contains carbon atoms joined by a triple bond
get a nice little chuckle out of the play on words. Use your knowledge of DNA
replication to write a bumper sticker.
_______________________________________________________________
_______________________________________________________________
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
7
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Section 3: Transcription
Study Guide B
KEY CONCEPT
Transcription converts a gene into a single-stranded RNA molecule.
VOCABULARY
messenger RNA (mRNA)
RNA
ribosomal RNA (rRNA)
transcription
transfer RNA (tRNA)
RNA polymerase
MAIN IDEA: RNA carries DNA’s instructions.
Label each of the processes represented by the arrows in the diagram below.
Write where each of these processes takes place in a eukaryotic cell in
parentheses.
1. _______________
DNA
RNA
2. _______________
_______________
Proteins
3. _______________
_______________
____________
Fill in the table below to contrast DNA and RNA.
DNA
RNA
4. Contains the sugar deoxyribose
5.
Has the bases A, C, G, and U
6. Typically double-stranded
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
8
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Study Guide B continued
MAIN IDEA: Transcription makes three types of RNA.
7. What enzyme helps a cell to make a strand of RNA?
_______________________________________________________________
8. Summarize the three key steps of transcription.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
9. Write the basic function of each type of RNA in the chart below.
Type of RNA
Function
mRNA
rRNA
tRNA
MAIN IDEA: The transcription process is similar to replication.
10. List two ways that the processes of transcription and replication are similar.
_______________________________________________________________
11. List two ways that the end results of transcription and replication differ.
_______________________________________________________________
Vocabulary Check
12. How does the name of each type of RNA tell what it does?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
13. What is transcription?
_______________________________________________________________
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
9
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Section 4: Translation
Study Guide B
KEY CONCEPT
Translation converts an mRNA message into a polypeptide, or protein.
VOCABULARY
translation
stop codon
codon
start codon
anticodon
MAIN IDEA: Amino acids are coded by mRNA base sequences.
1. What is translation?
_______________________________________________________________
2. What is a codon?
_______________________________________________________________
3. Would the codons in Figure 5.1(located in chapter 8 of the textbook) be found
in a strand of DNA or RNA?
_______________________________________________________________
4. What is a reading frame (look up in textbook)?
_______________________________________________________________
Refer to Figure 5.1 (located in chapter 8 of textbook) to complete the table below.
Codon
Amino Acid or Function
5. AGA
6. UAG
7.
tryptophan (Trp)
8. GGA
MAIN IDEA: Amino acids are linked to become a protein.
9. _______________ and _______________ are the tools that help a cell
translate an mRNA message into a polypeptide.
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
10
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Study Guide B continued
10. A tRNA molecule is attached to an _______________ at one end and has an
_______________ at the other end.
Fill in the cycle diagram below to outline the steps of translation.
Ribosome assembles on
start codon of mRNA
strand.
A.
B.
C.
When the ribosome
encounters a stop
codon, it falls apart and
the protein is released.
Vocabulary Check
11. What are AGG, GCA, and GUU examples of?
_______________________________________________________________
12. What is a set of three nucleotides on a tRNA molecule that is complementary
to an mRNA codon?
_______________________________________________________________
13. What do codons code for in addition to amino acids?
_______________________________________________________________
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
11
From DNA to Proteins
Name ______________________________ Class ___________________ Date __________________
Section 5: Gene Expression and Regulation
Study Guide B
KEY CONCEPT
Gene expression is carefully regulated in both prokaryotic and eukaryotic cells.
VOCABULARY
exon
intron
The diagrams below represent unprocessed and processed mRNA in a eukaryotic
cell. Using the diagrams as a reference, fill in the legend with the corresponding
element: cap, exon, intron, tail.
Legend
Unprocessed mRNA
Don’t Have to Fill In
Processed mRNA
Don’t Have to Fill In
Vocabulary Check
1. What is the difference between an exon and an intron?
_______________________________________________________________
_______________________________________________________________
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
12
From DNA to Proteins
Section 6: Gene Expression and Regulation
Name ______________________________ Class ___________________ Date __________________
Section 6: Mutations
Study Guide B
KEY CONCEPT
Mutations are changes in DNA that may or may not affect phenotype.
VOCABULARY
mutation
frameshift mutation
point mutation
mutagen
MAIN IDEA: Some mutations affect a single gene, while others affect an entire
chromosome.
1. List two types of gene mutations.
_______________________________________________________________
2. List two types of chromosomal mutations.
_______________________________________________________________
3. Which type of mutation affects more genes, a gene mutation or a chromosomal
mutation?
_______________________________________________________________
4. What leads to gene duplication?
_______________________________________________________________
5. What is a translocation?
_______________________________________________________________
Below is a string of nucleotides. (1) Use brackets to indicate the reading frame of
the nucleotide sequence. (2) Copy the nucleotide sequence into the first box and
make a point mutation. Circle the mutation. (3) Copy the nucleotide sequence into
the second box and make a frameshift mutation. Use brackets to indicate how the
reading frame would be altered by the mutation.
AGGCGTCCATGA
6.
7.
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
13
From DNA to Proteins
12.
Name ______________________________ Class ___________________ Date __________________
Study Guide B continued
MAIN IDEA: Mutations may or may not affect phenotype.
Fill in the cause-and-effect diagram below to explain how a point mutation may or
may not affect phenotype.
nonfunctional protein
coding regions
Point
mutations
result
in
9.
10.
may
occur
in
11.
result
in
8.
12.
no change
13. For a mutation to be passed to offspring, in what type of cell must it occur?
_______________________________________________________________
MAIN IDEA: Mutations can be caused by several factors.
14. Can DNA polymerase catch and correct every replication error?
_______________________________________________________________
15. What is a mutagen?
_______________________________________________________________
16. How does UV light damage the DNA strand?
_______________________________________________________________
_______________________________________________________________
Vocabulary Check
17. What is a mutation?
_______________________________________________________________
18. If a nucleotide is deleted from a strand of DNA, what type of mutation has
occurred?
_______________________________________________________________
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide B
14
From DNA to Proteins