DNA Manipulation

Question 1

Genetically Modified Organism

Answer 1

• aka Transgenic organisms
  An organism that is generated/altered through genetic engineering (being the direct manipulation of an organism’s genome using biotechnology)

Question 2

Recombinant Plasmid

Answer 2

A plasmid that has been altered by the insertion of genes/DNA fragments, achieved by a process catalysed by restriction enzymes and ligases

Question 3

Restriction enzymes

Answer 3

Enzymes with ability to cut and isolate DNA by breaking phosphodiester bonds between DNA nucleotides at a specific recognition site

Question 4

Ligases

Answer 4

Enzyme that assist in joining two pieces of DNA, usually from two different organisms, by allowing covalent bonds to form between sticky ends of the different DNA fragments

Question 5

Sticky vs Blunt ends

Answer 5

Sticky = single stranded, Blunt = double stranded, produced by restrictions enzymes cutting at a recognition site
Sticky ends find each other easier and faster due to their attraction to each other (forming covalent bonds)

Question 6

Primers

Answer 6

A short stranded DNA sequence added to either end of a DNA fragment to define the region of DNA to be amplified in the PCR process.

Question 7

Genes

Answer 7

A basic unit of hereditary, that is a sequence of DNA that encodes for a gene product (protein or RNA).

Question 8

Genetic Probe

Answer 8

A fragment of DNA or RNA of variable length used in DNA/RNA samples to detect the presence of nucleotide sequences of the DNA target that are complementary to it, and allows for probe-target base pairing once probe hybridizes.

Question 9

Transformed Bacteria

Answer 9

Occurs when bacteria takes up a genetically modified plasmid (a recombinant plasmid with inserted genes).
- recombinant plasmid + host cell = transformed cell

Question 10

Polymerase Chain Reaction: Purpose

Answer 10

a biochemical technology used to amplify copies of a piece of DNA

Question 11

Polymerase Chain Reaction: Steps

Answer 11

1. Denature DNA (heated to 94o for 2m)
2. Anneal Primers (add primers at 55o for 2m)
3. Extension (add TAQ polymerase and a supply of
   nucleotides at 72o for 1m)

Question 12

Gel Electrophoresis: Purpose

Answer 12

A method for separation and analysis of macromolecules (DNA, RNA, proteins) and their fragments based on their length and charge

Question 13

Gel Electrophoresis: Steps

Answer 13

1. Fragments of known DNA are cloned using PCR process
2. Fragments placed in wells of agar jelly
   - negatively charged DNA moves to positive electrode on other end of gel, and short pieces move faster

Question 14

Known DNA Standard

Answer 14

A piece of DNA consisting of fragments of known length

Used to estimate size of unknown DNA samples.

Question 15

Sterilisation techniques

Answer 15

Can be achieved by use of heat, chemicals, irradiation, high pressure, filtration to eliminate all forms of life and biological agents

Question 16

Ethical Methods

Answer 16

Replacement of animal research with other types of research wherever possible
Reduction of the number of animals used in research
Refinement of experimental techniques to minimise pain and distress