Description

Please answer the questions attached.

EXERCISE QUESTIONS
12.1 DNA Structure and Replication
DNA Structure
Observation: DNA Structure
1. Label phosphate, base pair, and deoxyribose in your drawing. See Figure 12.1

Base Colors

In Figure 12.1

Red Purple-blue Gold
Green

Table 12.1

  1. What type of molecules make up the backbone (uprights of ladder) of DNA (Fig. 12.1)? _____ and __________.
  2. Label a hydrogen bond in Figure 12.1. The label goes on the only write-on line available. Dashes are used to represent hydrogen bonds in Figure 12.1 because hydrogen bonds are_____________.
  3. Notice in Figure 12.1 and in your model that the base A is always paired with the base T, and the base C is always paired with the base G.
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Cytosine

Thymine

Adenine

Guanine

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Fig. 12.1

  1. In Figure 12.1, what molecules make up the rungs of the ladder?____________________________________________________________________ _________________________________________________________________________ _
  2. Why is DNA also called a double helix (Fig. 12.1)? – ___________________________________________________________________________ .

DNA Replication

Observation: DNA Replication

  1. What bonds are broken in order to unzip the DNA strands?
  2. Are your molecules identical?
  3. Because of complementary base pairing, each new double helix is composed of an ____strand and a ___strand.
    Why is DNA replication called semiconservative?___________________________________________________________________________ __________________________________________________________________________
  4. How does replication provide a means for passing DNA from cell to cell and organism to organism?
       ___________________________________________________________________________   ___________________________________________________________________________

Table 11. DNA Replication

12.2 RNA Structure
12. Describe the backbone of an RNA molecule.

   __________________________________________________________________________

13. Where are the bases located in an RNA molecule? ______________________________ Table 14.5 DNA and RNA Bases

15.3 DNA and Protein Synthesis
What is the role of each of these participants in protein synthesis? DNA: _________________________________________________ mRNA: _______________________________________________ tRNA: ________________________________________________

16. Transcription

What molecules does the cell require for
tanscription ___________________________________________________________________ ____________________________________________________________________________

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Old strand

GGGT T C C A T T AAA T T C C A GAAA T C A T A

New strand

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RNA Bases

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C

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U

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A

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G

DNA Bases

Observation: Transcription

17. The end (______) of the strand that will move to the ___________ in the cytoplasm. Table 18.6 Transcription

Observation: Translation

19. Why are the codons and anticodons in groups of three?___________________________. Table 20.7 Translation

21.4 Isolation of DNA and Biotechnology

Experimental Procedure: Gel Electrophoresis

  1. 22. What is biotechnology?
                __________________________________________________________________
                ____________________________________________________________
  2. 23. What is genetic engineering?
                __________________________________________________________________
                __________________________________________________________________
  3. 24. Speculate how the ability to isolate DNA and run gel electrophoresis of DNA relates to biotechnology.__________________________________________________________________ _________________________________________________________________
  4. 25. Name a biotechnology product someone you know is now using or taking as a medicine. InterferonGamma_________________________________________

DNA

T AC AC GAGC AAC T AAC A T

mRNA

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mRNA codons

AUG

CCC

GAG

GUU

GAU

UUG

UCU

tRNA anticodons

Amino acid

12.5 Detecting Genetic Disorders Genetic Sequence for Sickle Cell Disease

  1. In what one base does HbA differ from HbS?
  2. What are the codons for this base?
  3. What is the amino acid difference?

HbA CTC HbA GAG HbA glu

HbS CAC HbS GUG HbS val

Detection of Sickle-Cell Disease by Gel Electrophoresis
26. In Figure 12.12, which lane contains only HbS, signifying that the individual is HbSHbS.

lane ___
27. Which lane contains only HbA, signifying that the individual is HbAHbA. lane ____

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Fig. 12.2

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Detection by Genomic Sequencing

28.What are the chances that this couple will have a child with sickle-cell disease?

____________________________________________________________________________________________________________________________________________________________

Conclusion: Detecting Genetic Disorders

  • 29. What two methods of detecting sickle-cell disease were described in this section?____________________________________________________________________
  • 30. Which method is more direct and probably requires more expensive equipmentto do? ____________________________________________________
  • 31. Which method probably preceded the other method as a means to detect sickle-cell disease? ____________________________________________________LABORATORY REVIEW
    32. What biomolecule is composed of deoxyribose sugars, phosphates, and the nitrogen-containing bases adenine, guanine, cytosine, and thymine? _______

33.. What holds the nitrogen bases together in DNA? _______________

34.

What process makes a copy of DNA so that daughter cells that result from mitosis and cytokinesis each have a copy of DNA? ___________________

  1. Which five-carbon sugar is characteristic of RNA? ___________
  2. What nitrogen base is associated with RNA but not with DNA? ____________
  3. What kind of RNA is made when transcription occurs? ___________________
  4. Which strand of DNA is used to make mRNA? _____________________
  5. Where in a cell does protein synthesis occur? _______________________
  6. What molecule transports amino acids to the ribosomes? _________________
  7. How many nitrogen bases make up a codon, and what does each codon represent?
       ____________________
  8. What connects one amino acid to another in the polypeptide chain? ____________
  9. Which size DNA fragments, smaller or larger, move more quickly through a gel duringelectrophoresis? ____________
  10. How are many genetic disorders now identified? ___________________

45. What protein is affected when an individual has sickle-cell disease? _______________

Thought Questions

  1. Students sometimes get the impression that DNA must be replicated prior to proteinsynthesis. Explain why DNA is only replicated prior to the start of mitosis and meiosis and what the result would be if DNA was replicated each time a new protein needed to be made.___________________________________________________________________________ ___________________________________________________________________________
  2. If the portion of DNA to be transcribed has 66 bases, how many amino acids will the resulting protein have? Explain your reply.___________________________________________________________________________ ___________________________________________________________________________
  3. a. What concerns should high school and college athletic coaches have about the potential for their players to have sickle-cell trait?___________________________________________________________________________ ___________________________________________________________________________

49. How could players be identified as having sickle-cell trait or not?

____________________________________________________________________________________________________________________________________________________________