Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Genomics > PCR And It’s Role In Diagnostics > Flashcards

PCR And It’s Role In Diagnostics Flashcards

1
Q

What is PCR?

A

An enzyme based method to specifically amplify segments of DNA using a thermal DNA polymerase in a cyclical process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How many molecules do you have after ‘n’ cycles of a chain reaction?

A

2^n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

At what point is PCR done, and what does it mean?

A

Melting point of the primer, so under high stringency conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is a synonym for annealing?

A

Hybridisation of primers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How does PCR amplify specific DNA segments?

A

The primers hybridise to the chain, are recognised by DNA polymerase and forming the initiation complex around them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does exponential amplification require?

A

Two primers that are both complementary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the polymerase used in PCR?

A

DNA dependant DNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the newly formed strand in PCR called?

A

Nascent strand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does DNA dependant DNA polymerase do?

A

Recognises a specific structure that has a partially double stranded DNA forming an initiation complex with it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is a partially double stranded DNA structure formed?

A

By annealing a short single stranded DNA molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the efficiency of annealing and renaturation dependant upon?

A

The kinetics of the reactants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the DNA dependant DNA polymerase used to do?

A

To synthesise a new nucleic acid strand by copying a DNA molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What can’t DNA dependant DNA polymerase do?

A

Copy nor make RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does PCR need?

A

A template strand with an annealed primer
Deoxynucleotide triphosphates
Magnesium ions
A roughly neutral pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the four deoxynucleotide triphosphates?

A

dATP, dGTP, dCTP, dTTP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the three states PCR is dependant on?

A

Denaturing, annealing and the native state

17
Q

What is the native state in PCR?

A

Optimal extension temp and pH for enzyme activity

18
Q

What must the polymerase be in PCR?

A

Thermostable

19
Q

What are the stages (and temperatures) of PCR?

A

Mix the template, primers, enzyme and reactants
Denature (95C)
Anneal at the melting point of primer
Extend from the 3’ end of the primer (72C)

20
Q

What are the PCR reaction kinetics dependant on?

A

Depletion of reactants and acidification of the reaction

21
Q

What do the graphs of PCR reactions look like?

A

Sigmoidal linear curve or a straight line log graph with a plateau at the top

22
Q

What are the diagnostic applications of PCR?

A

Detecting TB in sputum
Differentiation between closely related organisms like swine flu and human influenza
HIV viral load
COVID testing

23
Q

How do you measure output of a PCR?

A

Quantitative or real-time PCR

24
Q

How does qPCR work?

A

Using a fluorescent detection of product at the end of each cycle

25
Q

What is a single nucleotide polymorphism (SNP)?

A

Single base alteration

26
Q

What is an example of a single nucleotide polymorphism (SNP)?

A

Sickle cell anaemia

27
Q

What are the common applications of single nucleotide polymorphism (SNP) detection?

A

Antibiotic resistance testing and ID of genetic markers

28
Q

What are the two approaches to single nucleotide polymorphism (SNP) detection?

A

High resolution melting and probe based qPCR (allelic discrimination)

29
Q

How does high resolution melting work?

A

The melting point of amplified products are used to determine which sequence variant is present

30
Q

How does allelic discrimination work?

A

Specific binding of the probe to the amplified region containing the SNP is detected

31
Q

How is PCR used in forensics and law enforcement?

A

Parentage or kinship, ID of military of missing people, crime scenes and authentification of biological material

32
Q

What are short tandem repeats (STRs)?

A

2-5 bps that are repeated many times at many places in the genome

33
Q

What does polymorphic mean?

A

Number of repeats vary between individuals but are similar between siblings and parents

34
Q

How many short tandem repeats (STRs) does the UK DNA database currently contain?

A

10

35
Q

What is the matching probability of the UK DNA database?

A

1 in 1 billion

36
Q

When else (not forensic or diagnostics) is PCR used?

A

For amplifying materials before doing next gen sequencing, manipulating and modifying DNA and for use with recombinant DNA tech

Genomics (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions