DNA tech. quiz

Question 1

Gene cloning

Answer 1

Produce multiple copies of a single gene and producing abundant protein from that gene.

Question 2

Restriction enzymes

Answer 2

Discovered in the 1960’s. These enzymes protect bacteria by cutting up foreign DNA at specific sites on a nucleotide sequence.

Question 3

DNA liagase

Answer 3

An enzyme that permanently bonds sticky ends together.

Question 4

Cloning vector

Answer 4

The original plasmid from a bacterium. May contain antibiotic resistance genes. This is the circle of DNA you will add your gene of interest to.

Question 5

Genomic library

Answer 5

• collection of cloned genes in a bacterium.
  Ie. Petri dish 1 - colony of bacteria containing the middle of the gene of interest.
  Petri dish 2 - colony of bacteria containing the end of the gene of interest.
  Petri dish 3 - colony of bacteria containing the beginning of the gene of interest.
  In reality genes can be very large and 10s-100s of plates would be needed to house all of the parts of a gene.

Question 6

BAC

Answer 6

Bacterial Artificial Chromosome

- a plasmid with many genes. These genes may function together, like the lac or tryp operon genes.

Question 7

cDNA

Answer 7

Complementary DNA made from mRNA with reverse transcriptase. No introns in the cDNA. Just exons that actually code for the needed protein.

Question 8

Bacterial Expression Vector

Answer 8

A plasmid with a strong promoter upstream from the cloned eukaryotic genes. Causes the expression of the gene.

Question 9

PCR

Answer 9

Polymerase Chain Reaction

- makes copies of small amounts of DNA.

Question 10

Gel Electrophoresis

Answer 10

Process separates DNA by size, by moving it through a gel with electricity.
Think of swimming through jello. Smaller pieces move faster than larger pieces.

Question 11

Southern Blot

Answer 11

Gel electrophoresis of DNA, hybridize with a labeled RNA and ssDNA. Allows you to find a gene of interest.

Question 12

Northern Blot

Answer 12

Gel electrophoresis of mRNA, hybridization with labeled RNA and ssDNA. Allows you to find mRNA of interest.

Question 13

Rt-PCR

Answer 13

Isolate mRNA, do PCR, run gel. DNA bands on the gel indicate the presence of the mRNA coding for DNA.
Ie. B-globin mRNA-a, B-globin mRNA-b, etc.

Question 14

In situ

Answer 14

In the organism

Question 15

In vitro

Answer 15

In a test tube or non-living test media.

Question 16

In vivo

Answer 16

In the organism

Question 17

DNA micro array assays

Answer 17

DNA attached to small glass slides or array. Probed with cDNA.

Question 18

RNAi

Answer 18

RNA interference

- double stranded RNA matches a gene sequence and block translation of mRNA. Knocks down gene expression.

Question 19

Totipotent cell

Answer 19

Differentiated cell that can dedifferentiate and form an entire, new adult organism.

Question 20

Reproductive cloning in mammals

Answer 20

Ie. Dolly - sheep that was cloned from a mammary cell nuclei + an enucleated sheep egg.
Produced a diploid cell which grew to an embryo.

Question 21

SNP

Answer 21

Single Nucleotide Polymorphism

- a single change in every 100-300 nucleotides. Unique to individuals, like fingerprint.

Question 22

RFLP

Answer 22

Restriction Fragment Length Polymorphism
A SNP in a gene can change a restriction site –> fragments of lengths other than the usual.
Ie. CCAATT/CCAATT/CCAATT normal gene sequence –> 3 CCAATT fragments
Ie. CCAATT/CCAAGTCCAATT A SNP of T removes one restriction site –> 2 fragments

Question 23

STR

Answer 23

Short Tandem Repeats
- repeated units of 2 - 5 base pairs in specific regions of a genome. The number of repeats varies from person to person and is an identifier like a fingerprint.

Question 24

GMO

Answer 24

Genetically Modified Organism

- genes added or removed

Question 25

Genetic engineering

Answer 25

Manipulation of genes for practical purposes

Question 26

DNA sequencing

Answer 26

Developed by Sanger 1980. Dideoxyribonucleotide method

Question 27

Plasmid

Answer 27

Small number of genes, replicates separately from bacterial DNA, may provide antibiotic resistance to the bacterium containing it.