BIOCHEMISTRY- Laboratory Techniques

Question 1

Which is the fundament for the polymerase chain Reaction?

Answer 1

Molecular biology laboratory procedure used to amplify a desired fragment of DNA

Question 2

Which are the three steps for the PCR in order to amplify DNA?

Answer 2

Denaturation
Annealing
Elongation

Question 3

What happens during DNA Denaturarion?

Answer 3

DNA is denatured by heating to generate 2 separate strands

Question 4

In this phase of PCR, during cooling, excess premade DNA primers anneal to a specific sequence on each strand to be amplified

Answer 4

Annealing

Question 5

In the Polymerase Chain Reaction, what happens during the elongation phase?

Answer 5

Heat-stable DNA polymerase replicates the DNA sequence following each primer

Question 6

TRUE OR FALSE… In the PCR the three steps are repeated just once

Answer 6

False, they´re repeated multiple times for DNA sequence amplification

Question 7

What is the use for aagarose gel electrophoresis?

Answer 7

Used for size separation of PCR products

Question 8

Which are the Blotting procedures?

Answer 8

Southern Blot
Northern blot
Western Blot
Southwestern Blot

Question 9

What does Southern blot studies?

Answer 9

DNA

Question 10

Which is the process followed for DNA studies in Southern blot?

Answer 10

DNA sample is enzymatically cleaved into smaller pieces, electrophoresed on a gel, and then transferred to a filter. In the filter the DNA is denaturant and anneals to its complementary strand. The resulting double stranded is visualized

Question 11

For what is useful the Northern blot?

Answer 11

RNA is electrophoresed

useful for studying mRNA levels which are reflective of gene expression

Question 12

What is studied with Western blot?

Answer 12

Proteins

Question 13

What is used to bind to relevant proteins in Western blot?

Answer 13

Labeled antibody

Question 14

What importance does a Western blot test has in a certain disease?

Answer 14

Confirmatory test for HIV after + ELISA

Question 15

So… Southwestern blot, what does it identifies?

Answer 15

DNA-binding proteins using labeled oligonucleotide probes

Question 16

This laboratory test is able to detect single nucleotide polymorphisms (SNPs) and copy number variations (CNVs)

Answer 16

Microarrays

Question 17

What does ELISA laboratory test means?

Answer 17

Enzyme linked immunosorbent assay

Question 18

What is the main purpose of ELISA?

Answer 18

Used to detect the presence of either a specific antigen or a specific antibody in a patient´s blood sample

Question 19

What does Direct ELISA detects?

Answer 19

antigen

Question 20

This ELISA test detects the antybody

Answer 20

Indirect ELISA

Question 21

Direct or Indirect ELISA test… uses a test antigen to see if a specific antibody is present in the patient blood

Answer 21

Indirect ELISA

Question 22

Direct or Indirect ELISA test… uses a test antibody to see if a specific antigen is present in the patient blood

Answer 22

Direct ELISA

Question 23

After the first step in ELISA, whats next?

Answer 23

A secondary antibody coupled to a color generating enzyme is added to detect either the antigen or the antibody depending if it is Direct or Indirect ELISA

Question 24

If the target substance is present in the sample, what are expecting to see?

Answer 24

Intense color reaction

Question 25

In HIV, what are we looking with ELISA... the antigen or the antibody?

Answer 25

Antibody... Anti-HIV

Question 26

For ELISA, how is the sensitivity and specifity?

Answer 26

Close to 100%, but both false positive and false negative can occur

Question 27

When there is a deletion too small to be visualized by karyotype, which test will you use?

Answer 27

Fluorescence in situ hybridization

Question 28

What is the fundament for the fluorescence in situ hybridization?

Answer 28

Fluorescent DNA or RNA probe bind to specific gene site of interest on chromosomes

Question 29

For what is useful the flourescence in situ hybriduzation?

Answer 29

Used for specific localization of genes and direct visulization of anomalies Microdeletions

Question 30

What are the cloning methods?

Answer 30

Cloning is the production of a recombinant DNA molecule that is self perpetuating

Question 31

Which are the Steps for the cloning method?

Answer 31

1. Isolate eukaryotic mRNA of interest 2. Expose mRNA to reverse transcriptase to produce cDNA (lacks introns) 3. Insert cDNA fragments into bacterial plasmids containing antibiotic resistance genes 4. Transform recombinant plasmid into bacteria 5. Surviving bacteria on antibiotic medium produce cDNA

Question 32

What is a Gene expresion modification?

Answer 32

For example, Transgenic strategies in mice involving removing or inserting a gene

Question 33

In the Gene expression modification, what is a cre-lox modification?

Answer 33

Can inducibly manipulate genes at specific developmental points

Question 34

In the Gene expression modification, what is RNA interference?

Answer 34

It´s knocking out or removing a gene

Question 35

Its a process in which methaphase chromosomes are stained, oredered, and numbered acording to morphology, size, arm-lenght ratio, and banding pattern

Answer 35

Karyotyping

Question 36

From where do we take the samples to do a Karyotyping

Answer 36

Sample of blood, bone marrow, amniotic fluid or placental tissue

Question 37

What diagnosis use does the karyotype has?

Answer 37

Chromosomal imbalances (autosomal trisomie, sex chromosomes disorders)

Question 38

What does Southern Blot study?

Answer 38

DNA using DNA probe in Elecrophoresis

Question 39

What is analized with Northern Blot?

Answer 39

RNA using DNA probe in elecrophoresis

Question 40

What is analized with Western Blot?

Answer 40

Proteins using 123 I- or enxyme linked antibody

Question 41

What is analized with Dot (slot) blot?

Answer 41

RNA , DNA or protein | NO ELECROPHORESIS

Question 42

Its purpose is to determine which restriction fragment of DNA is associated with a particular gene

Answer 42

Southern Blot

Question 43

Its purpose is to measure size and amounts of specific mRNA molecules to answer questions about gene expression

Answer 43

Northern blot

Question 44

Its purpose is to measure aoumns of antigen (proteins) or antibodies

Answer 44

Western Blot

Question 45

Its purpose is to detect specific DNA, RNA, proteins or antibodies

Answer 45

Dot (slot) Blot

Question 46

What determines which DNA fragments are seen in Southern Blot studies?

Answer 46

Probe

Question 47

Alternative name for polymorphysms VNTRS (variable number of tandem repeats)

Answer 47

Microsatellite repeats

Question 48

What does Northern blot measures?

Answer 48

mRNA | mRNA levels