3.5: Genetic modification and biotechnology
Teaching time: 4 hours Practical time: 0
key vocabulary
Prior learning and retrieval practice
Review 3.2 Chromosomes
Review 2.6 DNA structure
Essential idea: Biologists have developed techniques for artificial manipulation of DNA, cells and organisms.
Polymerase chain reaction - PCR
U2: PCR can be used to amplify small amounts of DNA.
Topic 2.7 A1: Use of Taq DNA polymerase to produce multiple copies of DNA rapidly by the polymerase chain reaction (PCR).
Exercise 1: Search the website below for the terms "PCR" and "Gel Electrophoresis". Connect - Extend - Challenge.
Exercise 2: Investigate the PCR process with this simulation: PCR Simulation
Gel Electrophoresis and DNA Profiles
U1: Gel electrophoresis is used to separate proteins or fragments of DNA according to size.
U3: DNA profiling involves comparison of DNA.
Topic 7.1 A3: Tandem repeats are used in DNA profiling.
A1: Use of DNA profiling in paternity and forensic investigations.
S2: Analysis of examples of DNA profiles.
Guidance from the syllabus: Students should be able to deduce whether or not a man could be the father of a child from the pattern of bands on a DNA profile.
Exercise 3: Complete this simulation: Gel Electrophoresis Lab Simulation
Genetic Modification
U4: Genetic modification is carried out by gene transfer between species.
A2: Gene transfer to bacteria using plasmids makes use of restriction endonucleases and DNA ligase.
Exercise 4: Follow the HHMI link on the left. Describe the process of genetic modification.
A3: Assessment of the potential risks and benefits associated with genetic modification of crops.
S3: Analysis of data on risks to monarch butterflies of Bt crops.
Exercise 5: Use the resources adjacent to discuss the risks and benefits of using GM crops
NoS: Assessing risks associated with scientific research—scientists attempt to assess the risks associated with genetically modified crops or livestock. (4.8)
GM crops risks and benefits
Cloning
U5: Clones are groups of genetically identical organisms, derived from a single original parent cell.
U6: Many plant species and some animal species have natural methods of cloning.
U7: Animals can be cloned at the embryo stage by breaking up the embryo into more than one group of cells.
U8: Methods have been developed for cloning adult animals using differentiated cells.
A4: Production of cloned embryos produced by somatic-cell nuclear transfer.
Guidance from the syllabus: Dolly can be used as an example of somatic-cell transfer. A plant species should be chosen for rooting experiments that forms roots readily in water or a solid medium.
Exercise 6: Explore the resource on cloning at Utah state university:
List natural methods of cloning
Outline how embryos can be cloned relatively cheaply
Describe the process of Somatic Cell Nuclear Transfer
Stem cuttings
S1: Design of an experiment to assess one factor affecting the rooting of stem-cuttings.
