Deck 5: Dna Quantitation

Question 1

What new characters and / or elements were introduced in this chapter?

A) Erica's father was an ex-marine who fought in Iraq
B) Erica acquired her auto mechanic skills from her father, Dwayne
C) Erica had a history of running away from home
D) Sam O'Neill, Erica Holmes boyfriend
E) All of the above

Answer 1

E

Question 2

What best describes the type of relationship Erica had with Sam?

A) very loving towards each other
B) plans were to eventually get married
C) good times and bad times
D) physically abusive relationship
E) very compatible with each other

Answer 2

C

Question 3

Why did Erica allow her boy friend to borrow her car?

A) He needed a larger car to transport a piece of furniture.
B) He needed a four-wheel drive vehicle.
C) She owned a truck which allowed him to haul debris to the city dump
D) He wanted to see how her newly purchased car was like to drive.
E) His car was in need of repairs.

Answer 3

E

Question 4

Dwayne Holmes became uncomfortable when Lt. Jenkins asked him about the mechanics garage (he was part owner) where Erica worked. Why?

A) Questions were raised about the financial records pertaining to the business.
B) Issues were raised about safety issues surround the garage employees
C) Questions about the employees having a criminal record
D) Issue of this workplace hiring illegal immigrants
E) None of the above

Question 5

What is the purpose of taking DNA samples and fingerprints from Erica's parents?

A) Obtain reference samples for latter comparison to samples processed from the crime scene
B) Lt. Jenkins believes that the parents are the suspects.
C) Samples could be used to determine origin of blood and fingerprints processed from the crime scene.
D) Choice a & b
E) Choice a & c

Question 6

Phone records indicated the Holmes received a call the evening their daughter disappeared from a Gary Furlong? Who is Gary Furlong?

A) ex-marine who fought with Dwayne during the Iraq war
B) an employee of the mechanics garage where Erica worked
C) their real estate agent
D) the families estate lawyer
E) a retired FBI agent

Question 7

When the Holmes received word that they have found their daughter's vehicle, who did Dwayne immediately accuse as the primary suspect surrounding the disappearance of their daughter?

A) Gary Furlong
B) Sam O'Neill
C) Chuck Beamer
D) Juan Gonzales
E) Sara Dawood

Question 8

When the Holmes were asked to speak with any of Erica's acquaintances who might be helpful, whose name came up?

A) Gary Furlong
B) Sam O'Neill
C) Chuck Beamer
D) Juan Gonzales
E) Sarah Dawood

Question 9

How were DNA samples obtained from the Holmes?

A) withdrew blood samples
B) took cheek cell samples
C) had them spit into a sterile tube
D) took samples from their toothbrushes
E) clipped a small sample from their head hairs

Question 10

In addition to DNA samples from the Holmes, they were asked to come down to the police station to provide

A) sworn statement about their whereabouts the day their daughter went missing
B) provide a report of last years income tax reports
C) bring their vehicles to the station to be inspected for trace evidence
D) identify the Subaru as belonging to their daughter
E) provide fingerprints

Question 11

In the initial beginning of detective work the saying goes…."before you go after the outlaws, first interrogate the in-laws". Explain what this phrase means.

Question 12

State reasons why Sam O'Neill (a) maybe included and (b) maybe excluded as the primary suspect in this missing persons case.

Question 13

How may Sasquatch, the family pet cat, play a roll in this case? Explain your response by citing specific examples.

Question 14

Dwayne, in his "rush to judgment," suspected Erica's boyfriend as the prime suspect. What other potential suspect did Dwayne implicate and why?

Question 15

Lt. Jenkins noted that a call was made from the Holmes residence to a Gary Furlong in Daly City. (a) What was the relationship between the Dwayne and Gary? (b) Why had Furlong provided very little information about the case?

Question 16

What is the central idea (s) in this chapter?

Question 17

A double-stranded DNA molecule is held together by….

A) Hydrogen bonds created by complimentary bases between adenine, thymine and guanine cytosine, respectively
B) Hydrogen bonds created by complimentary bases between adenine, guanine and thymine cytosine, respectively
C) Hydrogen bonds created by complimentary bases between adenine, thymine only.
D) Hydrogen bonds created by complimentary bases between guanine cytosine, only.
E) All of the above

Question 18

A nucleotide is a unit comprised of the following components

A) adenosine triphosphate, thymine, guanine, cytosine
B) phosphate, ribose sugar, hydrogen bonds
C) phosphate, ribose sugar, bases
D) hydrogen bonds created between complimentary bases
E) all of the above

Question 19

Which one of the following is a base pair mismatch?

A) Adenine pairs with Thymine
B) Cytosine pairs with Adenine
C) Guanine pairs with Cytosine
D) Thymine pairs with Adenine
E) Cytosine pairs with Guanine

Question 20

In the isolation and purification of extracting DNA from cells, a resin polymer by the name of Chelex is used. Which of the following best explains how it works?

A) represents the heat source that releases the DNA from a cell
B) binds to any charged ions that may degrade DNA
C) separates the DNA from the other cell components.
D) binds only to DNA molecules
E) allows DNA to precipitate out of solution.

Question 21

The Phenol-chloroform DNA extraction process creates two phases of separated liquids. Which layer will the DNA be found in…

A) the organic phase
B) the aqueous phase
C) both phases
D) right at the junction of the two phases
E) None of the above

Question 22

In a sexual assault, there is a mixture of DNA that needs to be resolved. How is this accomplished?

A) Proteinase K digests epithelial cells
B) Sodium dodecyl sulfate (SDS) digests epithelial cells
C) Centrifugation is used to separate cellular components
D) Choice 'a', &'b' are correct
E) Choice 'a', 'b', & 'c' are correct

Question 23

An instrument used to amplify DNA is a…

A) Centrifuge
B) Spectrophotometer
C) Thermocycler
D) Gel electrophoresis apparatus
E) Hemastix

Question 24

A spectrophotometer is an instrument that can determine the purity of a DNA sample by measuring the ratio of two wavelengths. The wavelength absorbance ratio is….

A) 260 nm divided by the 280 nm ratio
B) 200 nm t divided by the 300 nm ratio
C) 280 nm divided by the 300 nm ratio
D) 220 nm divided by the 260 nm ratio
E) none of the above

Question 25

Polymerase Chain Reaction (PCR) doesn't involve the following….

A) requires a source DNA referred to as the template
B) requires primers to bind to the template
C) requires a DNA polymerase enzyme
D) requires the presence of nucleotides
E) amplifies the entire amount of DNA in the original sample

Question 26

What are the three stages of PCR?

A) denature, anneal, replicate
B) anneal, extension, heating
C) denature, anneal, extend
D) denature, anneal, separate
E) anneal, electrophorese, extend

Question 27

What does the 5' to 3' rule means….

A) indicates the carbons in the nitrogenous bases
B) indicates the rule of complementarity i.e., adenine pairs with thymine and guanine pairs with cytosine
C) indicates the directionality that the DNA polymerase moves along the denatured DNA template.
D) choice 'a'& 'b' are correct
E) choice 'a','b', &'c' are correct

Question 28

Real time PCR can quantify DNA because …..

A) the amount of fluorescent light produced can be quantified using a spectrophotometer
B) the absence of fluorescent light produced indicates the amount of DNA amplified
C) the amount of fluorescent light produced is inversely proportional to the amount of amplified template DNA
D) the amount of fluorescent light produced is directly proportional to the amount of amplified template DNA
E) all of the above

Question 29

Function of the internal positive control (IPC) is to detect…

A) the presence of enzymes
B) the presence of RNA
C) the presence of primers
D) the presences of inhibitors
E) all of the above

Question 30

Real time PCR produces light because of the action of the…

A) DNA polymerase exonuclease activity on a probe that contains a reporter dye and quencher
B) RNA polymerase exonuclease activity on a probe that contains a reporter dye and quencher
C) DNA polymerase exonuclease activity on a probe that contains Chelex and chloroform
D) DNA polymerase exonuclease activity on a probe that contains only adenine and guanine in the DNA template
E) RNA polymerase exonuclease activity on a probe that contains only uracil

Question 31

Some bodily fluids are less apparent and require special enhancement techniques. Which of the following tools or techniques are used to visualize these more subtle stains?

A) Luminol
B) UV light source
C) orange filtered glasses
D) acid phosphatase and prostate specific antigens
E) all of the above

Question 32

Scientific Working Group on DNA analysis and the Technical Working Group on DNA Analysis Methods are….

A) leading organizations involved in best practices for handling of trace evidence
B) leading organizations involved in best practices for processing crime scenes
C) leading organizations involved in best practices for handling drugs
D) leading organizations involved in best practices for handling vehicular accident analysis
E) leading organizations involved in best practices for handling DNA

Question 33

Double-stranded DNA having an absorbance of 1.0 has a DNA concentration of…

A) 10 ug DNA/mL
B) 20 ug DNA/mL
C) 30 ug DNA/mL
D) 40 ug DNA/mL
E) 50 ug DNA/mL

Question 34

Single-stranded DNA having an absorbance of 1.0 has a DNA concentration of…

A) 13 ug DNA/mL
B) 23 ug DNA/mL
C) 33 ug DNA/mL
D) 43 ug DNA/mL
E) 53 ug DNA/mL

Question 35

Proteins are co-purified along with DNA. DNA absorbs maximally at…….proteins absorb maximally at…….

A) 260 nm; 280 nm respectively
B) 280 nm; 260 nm respectively
C) 160 nm; 180 nm respectively
D) 180 nm; 160 nm respectively
E) 200 nm; 300 nm respectively

Question 36

A 260 nm to 280 nm ratio of 1.8 is considered..

A) pure tRNA
B) pure mRNA
C) pure DNA
D) pure tRNA
E) pure mtDNA

Question 37

PCR (polymerase chain reaction) is a laboratory method for

A) amplifying the entire region of purified DNA
B) amplifying a defined region of purified DNA
C) amplifying the entire region of purified proteins
D) amplifying the entire region of purified proteins
E) all of the above

Question 38

The strand that's copied into a complimentary strand during PCR is called the

A) primer
B) extension
C) hydrogen bond
D) template
E) nitrogenous bases

Question 39

A Xerox or copy machine is similar to a thermocycler. Explain how a copy machine is similar and different to a thermocycler.

Question 40

Compare and contrast conventional PCR vs. real-time PCR.

Question 41

DNA is extracted from a suspect's blood by phenol/chloroform to determine if he was involved in a murder case. Thirty µL of the purified DNA is diluted in 970 µL of water (for a final volume of 1000 µL). That dilution is put into a quartz cuvette and its absorbance is read on a spectrophotometer at 260 nm. It gives a reading of 0.25. What is the concentration of DNA in the original sample? (phenol/chloroform extraction results in double stranded DNA use 50 ug DNA / mL = 1 O.D. to calculate concentration)

Question 42

A reference sample is needed from a victim of a sexual assault. Cells are recovered from a saline mouthwash procedure and the DNA is isolated by Chelex extraction. The DNA is diluted 40 µL into a total volume of 1000 µL and its absorbance is measured on a spectrophotometer at 260 nm. It gives a reading of 0.20. What is the concentration of DNA in the reference sample? (Chelex extraction renders DNA in a single stranded form, use 33 ug DNA / mL = 1 O.D. to calculate concentration)

Question 43

Ten µL of a suspect's reference DNA sample is diluted into 990 µL of water and its absorbance is read on a spectrophotometer. It gives an absorbance of 0.41 at 260 nm and an absorbance of 0.32 at 280 nm. What is its 260/280 ratio?

Question 44

If you recover 4000 cells from a saline mouthwash, how many µg of genomic DNA does that represent? [To solve this problem, you need to know that there are approximately 6 x 10⁹ bp of DNA per cell, that one mole of base pairs weighs 660 grams, that there are 1 x 10¹² pg/g, and that one mole of anything is 6.023 x 10²³ (Avogadro's number) of that thing.]

Question 45

What percent of your body weight is made up of DNA? Assume that your body consists of 1x10¹⁴ cells. (1 lb = 453.6 g)