Test over this material on Monday, 5/7


  • review DNA structure

  • go through the following information

  • finish through 4.4.8 for tomorrow

4.4.1 Outline the use of polymerase chain reaction (PCR) to copy and amplify minute quantities of DNA.

4.4.2 State that, in gel electrophoresis, fragments of DNA move in an electric field and are separated according to their size.

4.4.3 State that gel electrophoresis of DNA is used in DNA profiling.

4.4.4 Describe the application of DNA profiling to determine paternity and also in forensic investigations.
4.4.5 Analyse DNA profiles to draw conclusions about paternity or forensic investigations.

HW; read pages 168-170 and 165-167

4.4.6 Outline three outcomes of the sequencing of the complete human genome.
Outline means to give a brief account or summmary.
Begun formally in 1990 the international projects aims where:
  • identify all the approximate 30,000 genes in human DNA.
  • determine the sequences of the 3 billion chemical base pairs that make up human DNA.
  • store this information in database.
  • improve tools for data analysis.
  • transfer related technologies to the private sector.
  • address the ethical, legal, and social issues (ELSI) that may arise from the project.
  • To help achieve these goals, researchers also are studying the genetic makeup of several nonhuman organisms. These include the common human gut bacterium Escherichia coli, the fruit fly, and the laboratory mouse.

Benefits of the Human Genome Project (HGP)

improved disease diagnosis, identification of genetic disease carriers, drugs designed for specific genome, more insight and greater success in gene therapy, greater knowledge of family relationships through genetic testing, advances in forensic science for crime scene DNA analysis, improved knowledge of evolutionary relationships of humans, better understanding of human migration patterns

4.4.7 State that, when genes are transferred between species, the amino acid sequence of polypeptides translated
from them is unchanged because the genetic code is universal.
  • The genetic code is universal
  • All known organisms use the same genetic code.
  • Therefore in principle if we transfer a gene from one species to another it should still be transcribed and translated into the same protein.

4.4.8 Outline a basic technique used for gene transfer involving plasmids, a host cell (bacterium, yeast or other cell),
restriction enzymes (endonucleases) and DNA ligase.


genetically modified crops and cloning

read the rest of chapter 14

4.4.9 State two examples of the current uses of genetically modified crops or animals.
  • rice engineered with beta-carotene producing genes
  • pesticide resistant crop plants (can treat weeds when they're in amongst crop plants as crop plants are genetically engineered to be unharmed by the pesticide)

to get the genes in the cells:

  • viruses
  • naked DNA
  • plasmids
transformation of plant cells

animal cell transfection

4.4.10 Discuss the potential benefits and possible harmful effects of one example of genetic modification.


4.4.11 Define clone. Clone: a group of genetically identical organisms or a group of cells derived from a single parent cell.
  • reproductive cloning: to get an entire organism (bacteria, frogs, mice, sheep, goats, cows, mice, pigs, cats, rabbits)
  • therapeutic cloning: to get embryonic stem cells
  • mini-me clone

4.4.12 Outline a technique for cloning using differentiated animal cells.

4.4.13 Discuss the ethical issues of therapeutic cloning in humans. Therapeutic cloning is the creation of an embryo
to supply embryonic stem cells for medical use.