Evaluating Gene Expression

Question 1

Describe the difference between gene expression and gene regulation

Answer 1

Expression is where DNA is made into a functional gene product
Regulation gives the cell control over the structure and function

Question 2

What is a microarray

Answer 2

Miniature array of different DNA sequences in a glass surface which will undergo hybridisation.
Allows researchers to screen sample of DNA or RNA against thousand of genes simultaneously

Question 3

What is hybridisation

Answer 3

Sequence specific molecular recognition binding between 2 complementary molecules 
A:T(U)
C:G
DNA-DNA
cDNA-DNA
RNA-DNA

Question 4

True or false: RNA is a transient molecule

Answer 4

True

Question 5

What is cDNA

Answer 5

Strand of DNA that is complementary to part of an mRNA sequence

Question 6

What can reverse transcriptase be used for

Answer 6

Transcribes the reverse of mRNA into cDNA so Thymine is re-incorporated into the sequence

Question 7

True or false: sing stranded is more stable than double stranded

Answer 7

False

Question 8

True or false: Thymine is more stable than Uracil

Answer 8

True

Question 9

Steps for producing cDNA?

Answer 9

Isolation of mRNA from cell, add reverse transcriptase to make DNA strand, add RNAse to breakdown mRNA strand, DNA Polymerase to synthesise second DNA strand. Result is cDNA. Intron-less complete coding sequence of gene

Question 10

True or false: hybridisation doesn’t work on Double stranded molecules

Answer 10

True

Question 11

How do microarrays work

Answer 11

Mix cDNA or sample with fluorescent dye and then obtain measures of fluorescence