8.2

Question 1

Let’s Go Fishing

Answer 1

• Lake Sturgeon were abundant in many Ontario lakes
• Population decreased due to overfishing

*Lake sturgeon is a protected species under the
federal Fisheries Act

*Conservation officers now have a reliable tool
to help them enforce the ban: DNA

• Trent University has a Wildlife
  DNA Profiling and Forensics
  Laboratory

*Tracks and monitors endangered
species

Question 2

The Polymerase Chain Reaction (PCR)

Answer 2

• Technique used to make a large number of copies of a DNA
  sample from one biological source in just a few hours
• The procedure is:
  ✓Simple
  ✓Reliable
  ✓Fast
  ✓Inexpensive
• The whole process takes
  place in a small test tube,
  consisting of 3 steps
  1. Denaturation
  2. Annealing
  3. Elongation
• These steps are repeated in
  many cycles (usually 30-40)

Question 3

1. Denaturation

Answer 3

*DNA target sequence is
heated to 94-96°C

• H-bonds to break resulting in
  single strands

Question 4

2. Annealing

Answer 4

• The solution is cooled to 50-65°C
• Help DNA primers to anneal
  to each of the separated strands

Question 5

3. Elongation

Answer 5

• Two new DNA strands are heated to 72°C and act as
  templates
• Taq polymerase binds to primers and extends the DNA strands in the 5’ to 3’ direction
• After 3 cycles, 2 of the 8 DNA strands match the target sequence.
• Millions of DNA copies can be produced in just 2 hours from a tiny sample (e.g., hair follicle or blood).
• Amplified DNA can then be analyzed using techniques like gel electrophoresis

Question 6

Gel Electrophoresis

Answer 6

• A method of separating large molecules (such as DNA, RNA and proteins)
• Separates DNA fragments via aurgose gel
• Edithium bromide is used to stain DNA fragments
• -ivly charged DNA fragments travel
  through pores in the gel,
• Travels away from a -ve
  electrode at the START END and toward a +ve electrode at the DESTINATION END
• Smaller fragments moves faster than larger fragments

Question 7

DNA Sequencing

Answer 7

• A process in which the sequence of a strand of DNA
  is determined
• • Relies of the addition of labelled dideoxynucleotide (ddNTP) to a
    growing DNA strand
• The labels on the ddNTPs are dyes that fluoresce and can be used to
  identify the specific base when
  exposed to laser light

Question 8

Analyzing Genomes

Answer 8

• analyzed for its actual
  sequence (structural genomics) and/or for its function (functional
  genomics)
• Most research is focused on functional genomics, and it uses in bioinformatics
• Bioinformatics uses both lab experimental data and computerized
  analysis

Question 9

Nanopore Sequencing

Answer 9

• Individual strands of DNA pass through tiny microscopic holes
  called nanopores
• The sequence of the DNA is read as it passes through the pore by the unique electric current each base conducts

Question 10

DNA Microarrays

Answer 10

• Helps pinpoint the functions
  of specific genes, rather than
  just their locations
• Also, allows for comparison
  of gene expression
• Microarray, or gene chip, is
  designed to hold many
  individual DNA samples
• Advantageous because
  thousands of genes can be
  analyzed at the same time