Lab 12 Post-lab this shit was dumb

Question 1:  Which of the following components of a PCR reaction serves as building blocks to make new DNA molecules?

  water
  DNA polymerase
Correct!
  nucleotides
  primers

Question 2
1 / 1 pts
A.  POLYMERASE CHAIN REACTION (PCR), p. 190.

Questions for Review, p. 190.

Question 2:   Why are primers a necessary component of the PCR reaction?

  Primers help to establish the proper temperature for the reaction to proceed.
Correct!
  Primers assist DNA polymerase in attachment and initiation of DNA replication at the gene of interest.
  Primers act as a template that the DNA polymerase reads during the elongation steps.
  Primers reduce the likelihood that incorrect bases will be added during extension.

Question 3
1 / 1 pts
A.  POLYMERASE CHAIN REACTION (PCR), p. 190.

Questions for Review, p. 190.

Question 3:  Why must scientists use PCR when they are studying a single gene found in the human genome?

Correct!
  Scientists need many copies of the gene that they are studying  in their investigations.
  DNA is highly unstable under laboratory conditions, so scientists make copies so they have enough to last through their experiments.
  PCR helps molecular biologists to copy billions of base pairs of DNA (all the genes of a human) for genetic cloning.
  PCR is used to cut the DNA at specific sites, chosen by the researchers.

Question 4
1 / 1 pts
A.  POLYMERASE CHAIN REACTION (PCR), p. 190.

Questions for Review, p. 190.

Question 4:  Which of the following is NOT TRUE about PCR?

  PCR may be performed with a few simple ingredients and a thermocycler.
Correct!
  Approximately 100 copies of new DNA is generated by a typical PCR reaction.
  The DNA generated by PCR is identical to the parental DNA template strands at the gene of interest.
  PCR is a rapid technique that amplifies DNA in a few hours.

Question 5
1 / 1 pts
A.  POLYMERASE CHAIN REACTION (PCR), p. 190.

Questions for Review, p. 190.

Question 5:  Source DNA used for PCR ______________________________

  must be abundant, containing many copies of the template DNA strands.
  always needs to be highly purified before use in PCR
Correct!
  may be acquired from blood, skin, or even hair follicles.
  should be denatured and fragmented before beginning the reaction.

Question 6
1 / 1 pts
A.  POLYMERASE CHAIN REACTION (PCR), p. 190.

Questions for Review, p. 190.

Question 6:  All of the following components were added to your PCR reaction EXCEPT

  primers
  DNA polymerase
  nucleotides
Correct!
  DNA ligase

Question 7
1 / 1 pts
A.  POLYMERASE CHAIN REACTION (PCR), p. 191.

Questions for Review, p. 191.

Question 7:  What is the role of the thermocycler in the PCR reaction?

  It buffers the reaction to maintain the proper pH.
Correct!
  It establishes the proper temperatures to regulate the steps of the PCR reaction.
  It heats the PCR tubes to boiling and holds them at 95 oC throughout the entire process.
  It spins the DNA to the bottom of the PCR tube to separate the DNA from the liquid.

Question 8
1 / 3 pts
A.  POLYMERASE CHAIN REACTION (PCR), p. 191.

Questions for Review, p. 191.

Question 8:  Match the temperature of the PCR step with what is occurring at that stage.

Correct!
95 oC
You Answered
50 oC

Correct Answerprimers anneal to the single-stranded template strands of DNA
You Answered
72 oC

Correct AnswerDNA polymerase adds complementary nucleotides using the isolated DNA as a template

Question 9
0 / 1 pts
B.  RESTRICTION ANALYSIS, p. 191.

URL: http://labcenter.dnalc.org/labs/restrictionanalysis/restrictionanalysis_d.html (Links to an external site.)

EcoRI Cutting DNA Video.

Questions for Review, p. 191.

Question 9:  Based on the "EcoRI Cutting DNA" video, why were restriction enzymes of great interest to researchers like James Watson?

Correct Answer
  They were of value because they only cut DNA at specific target sequences.
  They were of value because they were found to randomly sheer DNA.
You Answered
  These enzymes successfully destroyed contaminating bacteria in their test tubes.
  These enzymes worked to ligate separate strands of DNA together.

Question 10
1 / 1 pts
B.  RESTRICTION ANALYSIS, p. 191.

Cutting and Pasting DNA Video.

Questions for Review, p. 191.

Question 10:  Based on the "Cutting and Pasting DNA" video, what sequence of DNA is recognized by EcoRI?

  GTTCTA
  GAATTG
  CAATTC
  TTAGAA
Correct!
  GAATTC

Question 11
0 / 1 pts
B.  RESTRICTION ANALYSIS, p. 191.

Cutting and Pasting DNA Video.

Questions for Review, p. 191.

Question 11:  What is generated by the cleavage of DNA with EcoRI?  When EcoRI acts on a restriction site within a DNA molecule, it _____________________.

  cuts unevenly, producing blunt ends.
  cuts evenly, producing blunt ends.
Correct Answer
  cuts unevenly, producing sticky ends.
You Answered
  cuts evenly, producing sticky ends.

Question 12
1 / 1 pts
B.  RESTRICTION ANALYSIS, p. 191.

Cutting and Pasting DNA Video.

Questions for Review, p. 191.

Question 12:  How does the enzyme DNA ligase function?

  It creates a peptide bond between neighboring sugar and phosphate groups.
  It keeps the restriction enzyme from denaturing during the reaction.
Correct!
  It seals together DNA molecules that have been cleaved with the same restriction enzyme.
  It speeds up the elongation of DNA.

Question 13
1 / 1 pts
C.  GEL ELECTROPHORESIS, p. 192.

URL: http://learn.genetics.utah.edu/content/labs/ (Links to an external site.).

Questions for Review, p. 192.

Question 13:  What is the purpose of gel electrophoresis?

  Gel electrophoresis magnifies DNA so that it is large enough to see a single DNA strand.
  Gel electrophoresis cuts DNA into many fragments.
  Gel electrophoresis replaces faulty genes in human cells.
Correct!
  Gel electrophoresis separates DNA fragments based upon length.

Question 14
1 / 1 pts
C.  GEL ELECTROPHORESIS, p. 192.

Questions for Review, p. 192.

Question 14:  Because DNA is ________ charged, it migrates toward the _________ pole (end) of the gel when an electrical current is passed through the gel.

  positively, positive
  positively, negative
  negatively, negative
Correct!
  negatively, positive

Question 15
5 / 5 pts
C.  GEL ELECTROPHORESIS, p. 192.

Questions for Review, p. 192.

Question 15:  What is the function of the following in gel electrophoresis: comb, gel box, micropipette, loading buffer, DNA size standard?  Match the following.

Correct!
comb
Correct!
gel box
Correct!
micropipette
Correct!
loading buffer
Correct!
DNA size standard

Question 16
1 / 1 pts
C.  GEL ELECTROPHORESIS, p. 192.

Gel electrophoresis-Hook up the electrical current and run the gel.

Questions for Review, p. 192.

Question 16:  How does one know that current is running through the gel?

  The gel will turn blue under special lighting.
  The buffer becomes cloudy.
Correct!
  Bubbles will surface in the gel box.
  DNA will move out of the wells and into the buffer.

Question 17
1 / 1 pts
C.  GEL ELECTROPHORESIS, p. 192.

Gel electrophoresis-Stain the gel and analyze the results.

Questions for Review, p. 192.

Question 17:  Which of the following chemicals may be used to stain the gel after it is run?

  ligase
  primers
  agarose
Correct!
  ethidium bromide
  EcoRI

Question 18
1 / 1 pts
C.  GEL ELECTROPHORESIS, p. 193.

Gel electrophoresis-Stain the gel and analyze the results.

Questions for Review, p. 193.

Question 18:  What protective equipment is required to stain and visualize a gel using ethidium bromide? Choose TWO answers.

  a lead apron/body shield
Correct!
  disposable gloves
  a gas mask
Correct!
  protective goggles or face shield

Question 19
1 / 1 pts
C.  GEL ELECTROPHORESIS, p. 193.

Gel electrophoresis-Stain the gel and analyze the results.

Questions for Review, p. 193.

Question 19:  What was the approximate length of the DNA molecule closest to the top of the gel (in the first well) on your virtual gel?  (Note:  The top of the gel is where the samples were loaded.)

  15,000 bp
  7,000 bp
Correct!
  6,000 bp
  3,200 bp

Question 20
1 / 1 pts
C.  GEL ELECTROPHORESIS, p. 193.

Gel electrophoresis-Stain the gel and analyze the results.

Questions for Review, p. 193.

Question 20:  What was the approximate length of the DNA molecule in the middle of the gel (in the first well) on your virtual gel?

  5,000 bp
Correct!
  3,500 bp
  2,500 bp
  1,700 bp

Question 21
1 / 1 pts
C.  GEL ELECTROPHORESIS, p. 193.

Gel electrophoresis-Stain the gel and analyze the results.

Questions for Review, p. 193.

Question 21:  What was the approximate length of the DNA molecule at the bottom of the gel (in the first well) on your virtual gel?

  3,000 bp
  2,000 bp
Correct!
  1,500 bp
  500 bp

Question 22
0 / 1 pts
POST-LAB QUESTIONS, p. 193.

1.  How is DNA technology used in science, society, and in medicine?  Which of the following would be considered an example of biotechnology?

  Growing cancer cells in a petri dish
Correct Answer
  Developing a rice plant that produces a precursor to Vitamin A
  Brewing beer
You Answered
  Crossing a wild corn plant with a domesticated corn plant

Question 23
1 / 1 pts
POST-LAB QUESTIONS, p. 193.

2.  After a gel is run, would you expect to find smaller DNA fragments closer to the bottom or closer to the top of the gel?  Why?

Correct!
  Smaller DNA fragments would migrate closer to the bottom of the gel since they travel faster through the porous gel relative to the larger DNA fragments.
  The smaller DNA fragments would migrate closer to the top of the gel since they travel slower through the porous gel relative to the larger DNA fragments.
  All fragments, regardless of size, would travel at the same speed through the gel.