Download BIOLOGY Cells Unit GUIDE SHEET

DNA - Unit Study Guide
How does the structure of a molecule of DNA contain enough information to code for an
entire living organism?
How does the structure of a molecule of DNA enable information to be
copied and passed down from a parent organism to its offspring?
How does DNA code for the production of proteins?
CHAPTER 8: “THE CELLULAR BASIS OF REPRODUCTION AND INHERITANCE”
CHAPTER 10: “MOLECULAR BIOLOGY OF THE GENE”
Questions:
PART I: THE BIG PICTURE!!!
Explain how DNA is the “blueprint” for a living organism. What information does it carry and how does it code
for an entire living organism? HINT: What is “The CENTRAL DOGMA?” (see pages 190-191, especially
Figures 10.6A and 10.7)
PART II: CELL DIVISION
1. What essential life processes require cell division (see, for example, pages 125-127 and 136)?
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2. In what way is cancer a disease of cell division (page 125 and 135)?
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3. Why is it absolutely essential that DNA replication occur before each round of cell division?
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4. What is a chromosome? Explain HOW and WHY DNA is packaged into chromosomes. In your answer
include and explain the terms chromatin, sister chromatids, and centromere (pages 126-128).
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5. In the space below draw a diagram of the cell cycle (page 129). Be sure to include and explain the terms:
Interphase, DNA replication (DNA synthesis), Mitosis, Cytokinesis, G-phase, S-phase, and Mitotic phase.
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Complete the activity Mitosis Web Quest: Online Onion Root Tips
6. Draw and explain what occurs during each of the following stages of the cell cycle (pages 129-131):
a. Interphase:
b. Prophase:
c. Prometaphase:
d. Metaphase:
e. Anaphase:
f. Telophase:
g. Cytokinesis:
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7. What essential role do the centromere, mitotic spindle, and centrosomes play during mitosis (pages 128 and
130-131)? What will happen to the chromosomes of a cell if these structures do not function properly?
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8. Label the diagram below to indicate the phase of mitosis shown in each picture (pages 130-131).
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PART III: DNA STRUCTURE AND REPLICATION
COMPLETE THE ACTIVITY “GIZMO Student Exploration: Building and Replicating DNA”
available at www.explorelearning.com
login: username _____________________________ password __________________
1. Describe the overall shape of the DNA molecule (pages 186-187).
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2. a) Please label the three major parts of a
nucleotide as shown below (page 184).
b) Label the DNA molecule below to indicate its structural
components. Use the terms: deoxyribose sugar, phosphate,
nitrogen base, nucleotide, sugar-phosphate backbone, base pair,
and hydrogen bond. Then write in the complementary base
sequence of the second strand (page 184-187).
3. What are the “Base-pairing Rules” and how do they relate to the structure of DNA (pages 186-189)?
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4. What do we mean by saying that the DNA base pairs are “complementary”? How is this relationship
important to the structure and function of DNA? (pages 186-189)
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5. Write in the nitrogenous base sequence for the other half of the DNA molecule below (pages 186-189).
G C T A C G T A C A A G A T G A C A A T T
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6. If a given piece of double stranded DNA contains 26% Adenine, what are the percentages of each of the other
three nitrogenous bases in that piece of DNA? SHOW YOUR WORK!!!
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7. Using the diagrams below, describe each step of DNA replication, including the names of any enzymes
required for each step (pages 188-189).
a. ______________________________________________________________
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b. ______________________________________________________________
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c. _____________________________________________________________
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d. _____________________________________________________________
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8. What is meant by saying that the process of DNA replication is “semi-conservative” (pages 188-189)?
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9. How do your cells guard against errors in DNA replication (page 189)?
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10. In what ways can errors in DNA replication be useful to a species (page 199)?
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PART IV: PROTEIN SYNTHESIS
COMPLETE THE ACTIVITY “GIZMO Student Exploration: RNA and Protein Synthesis”
available at www.explorelearning.com
login: username _____________________________ password _______________
1. Explain what is meant by the statement “DNA is the recipe for protein.” (see pages 190-191)
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2. Using the WORD BANK below, label the diagram of protein synthesis below to show the three parts of the
eukaryotic cell, and the four molecules and two major steps from gene to protein (pages 190-191).
WORD BANK: nucleus
amino acids
cytoplasm
protein
ribosome
transcription
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DNA
translation
mRNA
3. Using your labeled diagram above to help you, explain how the structure of DNA codes for a specific
protein. Be sure to include all of the terms from the WORD BANK in your answer (pages 190-191).
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4. Use the WORD BANK below to compare the structures of DNA and RNA in the Venn diagram.
Write each phrase within the area on the diagram that shows whether the characteristic belongs to both
DNA and RNA, only to DNA, or only to RNA (pages 184-185).
WORD BANK:
single-stranded
double-stranded
contains deoxyribose sugar
contains ribose sugar
made up of nucleotides
contains guanine (G) base
contains thymine (T) base
contains uracil (U) base
DNA
contains cytosine (C) base
contains adenine (A) base
never leaves the nucleus
can leave the nucleus
RNA
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5. Compare and contrast the 3 major types of RNA including full name, structure, function, and location
in a cell (pages 194-196).
mRNA
rRNA
tRNA
6. Explain why the Genetic Code, shown in the table to the right, is referred to as “redundant” (page 192)
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7. Explain why the Genetic Code is called “universal” (p 192).
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Genetic Code (mRNA)
8. Use the Genetic Code above to determine the amino acid sequence given by each of the following:
a. If the mRNA sequence of bases is AUGGUCAAUCCAUGC
b. If the DNA sequence of bases is TACCGGGCATTCAAA (hint: this first requires an extra step):
9. Use the Genetic Code above to determine TWO DIFFERENT possible mRNA base sequences for the amino
acid sequence Valine- Lysine-Leucine:
a. ____________________________________________________
b. ____________________________________________________
10. Identify the following key terms in understanding DNA and protein synthesis. Match each term in
Column B with the correct definition THAT YOU WRITE in Column A. Write the letter of the correct term on
the line provided.
COLUMN A
COLUMN B
_____ building blocks of protein
a. Amino Acids
_____ building blocks of DNA & RNA
b. Chromosome
c. Codon
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d. Anticodon
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e. Gene
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f.
mRNA
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g. tRNA
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h. Mutation
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i.
Transcription
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j.
Translation
k. DNA Replication
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l.
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Nucleotide
m. Protein
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n. Ribosome
_____
_____
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11. Explain what a mutation is. Describe some sources of mutations (see page 199).
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12. Explain why doctors recommend that you use UVA/UVB sunblock when going outside.
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13. Explain why a point mutation (the replacement of one nucleotide and its base-pairing partner with
another pair of nucleotides) may or may not result in a change in the amino acid sequence of a protein. In your
answer use and define the terms silent mutation, missense mutation, and nonsense mutation (page 199).
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14. Explain why frameshift mutations (mutations involving the insertion of deletion of one or more
nucleotides in a gene) usually have major effects on the amino acid sequence of a protein (page 199).
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15. Compare and contrast the two types of mutations in the table below.
Then, provide a specific example of each type of mutation as follows:
1. Using the DNA sequence TACCGGGCATTCAAA as a starting point, make a mutation of the indicated type.
Write your mutated DNA sequence.
2. Using the Genetic Code from page 9, show the amino acid sequence coded for by your mutated DNA
sequence (don’t forget to make mRNA first!!!)
Point mutation
Frameshift mutation
COMPARE AND CONTRAST
SPECIFIC EXAMPLES
Original DNA sequence:
TACCGGGCATTCAAA
Mutated DNA sequence:
Original DNA sequence:
TACCGGGCATTCAAA
Mutated DNA sequence:
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