Laboratory Techniques

Question 1

Best test to determine whether a gene is being expressed

Answer 1

Northern blot

Question 2

What is the polymerase chain reaction used for

Answer 2

Amplify a desired fragment of DNA

Question 3

Polymerase chain reaction steps

Answer 3

1. Denaturation (DNA is denatured by heating to separate the strands)
2. Annealing (during cooling, excess DNA primers anneal to a specific sequence on each strand to be amplified)
3. Elongation (heat-stable DNA polymerase replicates the DNA sequence following each primer)

Question 4

What is RT-PCR used for

Answer 4

It is used to detect and quantify levels of messenger RNA in a sample

*mRNA - RT - cDNA - PCR - amplification

Question 5

Southern blotting is used to measure what type of molecule

Answer 5

DNA

Question 6

Enzymes used in southern blotting to cleave DNA samples in smaller pieces

Answer 6

Restriction endonucleases

*Restriction site mutations can be detected using this because they alter DNA lengths

Question 7

Blotting technique used to assess level of gene expression

Answer 7

Northern blot

*As it studies mRNA levels, these are reflective of gene expression

Question 8

Blotting technique that uses labeled antibodies to bind relevant proteins

Answer 8

Western blot

Question 9

Blotting technique that identifies DNA-binding proteins using labeled oligonucleotide probes (dsDNA)

Answer 9

Southwestern blot

Question 10

Cellular characteristics evaluated by flow cytometry

Answer 10

Size, granularity, and protein expression (immunophenotype)

Question 11

Describe the process of flow cytometry

Answer 11

Cells are tagged with antibodies specific to surface or intracellular proteins - these are then tagged with a unique fluorescent dye - sample is the analyzed one cell at a time by focusing a laser on the cell and msasuring light scatter and intensity of fluorescence

Question 12

Laboratory technique used to profile gene expression levels of thousands of genes simultaneously

Answer 12

Microarrays

Question 13

Laboratory technique that is able to detect single nucleotide polymorphisms (SNPs) and copy number variations (CNVs)

Answer 13

Microarrays

Question 14

Laboratory technique that detects specific antigens or antibodies through the use of a reaction with an antibody-linked enzyme

Answer 14

Enzyme-linked immunosorbent assay

Question 15

To do a karyotype, chromosomes need to be in which cell cycle phase

Answer 15

Metaphase

Question 16

Laboratory technique that uses fluorescent DNA or RNA probes that bind to specific gene sites of interest on chromosomes

Answer 16

Fluorescence in situ hybridization (FISH)

Question 17

Main difference between chromosomal DNA and complementary DNA

Answer 17

cDNA lacks introns

Question 18

Laboratory technique used to manipulate genes at specific developmental points (eg, study a gene whose deletion causes embryonic death)

Answer 18

Cre-lox system

Question 19

How does RNA interference down-regulates gene expression

Answer 19

dsRNA is synthesized that is complementary to the mRNA sequence of interest - when transfected into human cells, dsRNA separates and promotes degradation of target mRNA