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)

Genetic engineering | HHMI's BioInteractiveA new gene can be inserted into a loop of bacterial DNA called a plasmid. This is done by cutting the plasmid DNA with a restriction enzyme, which allows a new piece of DNA to be inserted. The ends of the new piece of DNA are stitched together by an enzyme called DNA ligase. The genetically engineered bacteria will now manufacture any protein coded by genes on the newly inserted DNA.

GM crops risks and benefits

http://learn.genetics.utah.edu/content/science/gmfoods/

Genetically modified (GM) plants: questions and answersThe Royal Society commissioned a report into what people want to know about GM plants, and then drew on a panel of independent scientists.

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.

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