Download Homework packet ch 13

Unit 6 Vocabulary: Define the following vocabulary terms:
RNA
messenger RNA
ribosomal RNA
transfer RNA
Transcription
RNA polymerase
Promoters
Introns
Exons
Polypeptides
Genetic code
Codon
Translation
Anticodon
Gene expression
Mutations
Point mutations
Frameshift mutations
Mutagens
Polyploidy
Operon
operators
RNA interference
Differentiation
Homeotic genes
Homeobox genes
Hox genes
13.1 RNA (362-365)
The Role of RNA
1. Complete the table to contrast the structures of DNA and RNA
Sugar
Number of Strands Bases
DNA
RNA
a. ______________
b. _______________
c. ______________
3. The master plan of a building shows how to build and place important parts of a building, such as walls,
pipes and electrical outlets. On the building site, workers use copies of the master plan called blueprints to
show them what to do. The master plan is kept in the office. Explain how mRNA works like a blueprint in
constructing proteins. ______________________________________________________________________
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For questions 4-10, complete each statement by writing the correct word or words.
4. The process of using DNA to produce complementary RNA molecules is called ______________________.
5. The sequence of ______________ in mRNA complements the sequence in the DNA template.
6. In eukaryotes, RNA is formed in the ___________________ and then travels to the ___________________.
7. The enzyme ___________________________ binds to DNA during transcription.
8. RNA polymerase binds to regions of DNA called ___________________, which are “start” signals for
transcription.
9. _________________ are portions of RNA that are cut out and discarded.
10. _______________ are spliced together to make the final mRNA.
13.2 RIBOSOMES and PROTEIN SYNTHESIS (366-371)
The Genetic Code Use the diagram to answer Questions 1-7
1. What are the words along the
outside of the circle?
_________________________________________
2. What can you find by reading
this diagram from the inside out?
_________________________________________
3. For which amino acid is AAA a codon?
_________________________________________
4. What is the codon for tryptophan?
_________________________________________
5. For which amino acid is GGA a codon?
_________________________________________
6. What is the codon for alanine? _____________________________
7. What are the three other codons for alanine? __________________________________________________
8. What is the codon used to start protein synthesis? ____________________
Translation
Use the diagram to answer Questions 1-10.
9. What is the anticodon for leucine? _________
10. What is the codon for leucine? _________
11. List the amino acids in the order they would
appear in the polypeptide coded for by this mRNA
_________________________________________
12. What is the difference between transcription
and translation? ___________________________
________________________________________________________________________________________
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13. Complete the table to describe the steps in protein synthesis
Step
Beginning of
translation
Description
Assembly of
polypeptides
Completing the
polypeptide
14. Describe the role of rRNA during translation
________________________________________________________________________________________
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The Molecular Basis of Heredity For questions 15-19, write the letter of the correct answer on the line at the left
________ 15. The instructions for assembling proteins are contained in the
a. genetics
b. ribosomes
c. exons
d. introns
_______16. The central dogma of molecular biology is that information is transferred from
a. RNA to protein to DNA
c. protein to DNA to RNA
b. DNA to protein to RNA
d. DNA to RNA to protein
_______17. An exception to the central dogma is
a. the infection of a virus by a bacteriophage
b. the ability of some viruses to transfer information from RNA to DNA
c. the expression of different genes during different stages of development
d. the translation of the codon into the anticodon of tRNA
_______18. The way in which DNA, RNA, and protein are all involved in putting the genetic information into
action in living cells is called
a. translation
b. transcription
c. gene expression
d. viral transfer
_______19. All organisms are mostly the same in
a. the proteins they make on their ribosomes.
b. how their proteins catalyze chemical reactions.
c. the size of their genes.
d. the molecular biology of their genes.
20. Whether the organism is a pea plant or a human being, the information in the DNA of the cell’s nucleus
directs synthesis of protein in the cytoplasm. Why, then, are pea plants and human beings so different?
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13.3 MUTATION (372-376)
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13.4 GENE REGULATION & EXPRESSION (377-383)
1. How do prokaryotes conserve energy?
__________________________________________________________________________________________
2. How do DNA-binding proteins in prokaryotes regulate genes?
__________________________________________________________________________________________
3. What is an operon?
__________________________________________________________________________________________
4. What is in the lac operon in E. coli?
__________________________________________________________________________________________
5. What is the function of the genes in the lac operon of E. coli?
__________________________________________________________________________________________
6. What turns the lac operon off?
__________________________________________________________________________________________
7. How does a repressor protein turn off the lac operon?
__________________________________________________________________________________________
8. How does lactose turn on the lac operon?
__________________________________________________________________________________________
9. Complete the table to describe the role of each regulatory region or molecule in the operation of the lac
operon
Regulatory Region or Molecule
What It Does
Repressor protein
Operator
RNA polymerase
Lactose
Eukaryotic Gene Regulation
10. In what two ways is gene regulation in eukaryotes different from gene regulation in prokaryotes?
___________________________________________________________________________
___________________________________________________________________________
11. What is a TATA box? What does a TATA box do?
___________________________________________________________________________
___________________________________________________________________________
12. What are transcription factors and what do they do?
___________________________________________________________________________
___________________________________________________________________________
13. Explain how gene regulation makes cell specialization possible.
___________________________________________________________________________
___________________________________________________________________________
14. What is microRNA and how is it related to mRNA?
___________________________________________________________________________
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15. Explain how the process of RNA interference works.
___________________________________________________________________________
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Genetic Control of Development
____ 16. As an embryo develops, different sets of genes are regulated by
A. mRNA & lac repressors
B. operons and operators
C. transcription factors and repressors
D. promoters & operators
____ 17. The process through which cells become specialized in structure and function is
A. transcription. B. gene expression. C. differentiation. D. RNA interference.
____ 18. Homeotic genes are
A. regulator genes that bind to operons in prokaryotes.
B. master control genes that regulate organs that develop in specific parts of the body.
C. parts of the silencing complex that regulates gene action through RNA interference.
D. base sequences complementary to sequences in microRNA.
_______ 19. What role do homebox genes play in cell differentiation?
A. The code for transcription factors that activate other genes important in cell
development and differentiation
B. They block certain gene expression
C. They cut double-stranded loops into microRNA
D. They attach to a cluster of proteins to form a silencing complex, which binds to and
destroys certain RNA
_______ 20. In flies, the group of homeobox genes that determines the identities of each segment of a
fly’s body is the group known as
A. silencing complexes
B. promoters
C. operators
D. hox genes
_______ 21. Clusters of Hox genes are found in
A. flies only
B. flies and frogs only
C. plants only
D. nearly all animals
_______ 22. The “switches” that trigger particular patterns of development and differentiation in cells
and tissues are
A. mRNA molecules B. master control genes C. silencing complexes D. dicer enzymes
_______ 23. Metamorphosis is
A. a series of transformations from one life stage to another
B. the master switch that triggers development and differentiation
C. the product of interactions among homeotic genes
D. the process by which genetic information is passed from one generation to the next
24. Environmental factors can influence gene expression. Fill in the table below to show how organisms
respond to conditions in their environment
Environmental Factor Influencing
How the Organism Responds
Gene Expression
E. coli with limited food supply
Nutrient availability
A tadpole in a drying pond
25. Many research studies have shown that different species may possess some of the exact same genes but
show vastly different traits. How can that happen?
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18. The diagram below shows a normal gene
sequence and three mutual sequences of a segment
of DNA