Genetic Engineering Noadswood Science, 2016

Thursday, September 20, 2018 Genetic Engineering To describe the processes involved with genetic engineering

Precise Learning Students should be able to describe genetic engineering as a process which involves modifying the genome of an organism by introducing a gene from another organism to give a desired characteristic Plant crops have been genetically engineered to be resistant to diseases or to produce bigger better fruits Bacterial cells have been genetically engineered to produce useful substances such as human insulin to treat diabetes In genetic engineering, genes from the chromosomes of humans and other organisms can be ‘cut out’ and transferred to cells of other organisms. Crops that have had their genes modified in this way are called genetically modified (GM) crops. GM crops include ones that are resistant to insect attack or to herbicides. GM crops generally show increased yields In genetic engineering: enzymes are used to isolate the required gene; this gene is inserted into a vector, usually a bacterial plasmid or a virus (higher tier only) the vector is used to insert the gene into the required cells (higher tier only) genes are transferred to the cells of animals, plants or microorganisms at an early stage in their development so that they develop with desired characteristics (higher tier only)

Genetic Engineering How have humans changed the genetic make-up of organisms that we have taken advantage of? Selective breeding - only breeding the organisms with the characteristics we wanted Genetic engineering takes genes from one organism, and places them into the chromosomes of another organism…

Genetic Engineering Genetic engineering takes genes from one organism, and places them into the chromosomes of another organism. It alters an organism's genetic code, and works because there is only one code for life The set of instructions for which a gene is responsible work whichever organism the gene is in, e.g. a gene for luminescence from a jellyfish can be added to a frog, making it luminescent too!

Method Enzymes are used to cut up and join together parts of the DNA of one organism, and insert them into the DNA of another organism In the resulting new organism the inserted genes will code for one or more new characteristics - for example producing a new substance, or performing a new function The organism has been genetically re-engineered E.g. a bacterium's genetic make- up can modified by splicing a gene into its DNA

Method – Detailed Certain enzymes can cut pieces of DNA from one organism, and join them into a gap in the DNA of another organism The new organism with the inserted genes has the genetic information for one or more new characteristics, e.g. the organism might produce a useful substance, or be able to carry out a new function The method can be used to produce bacteria that produce insulin (valuable hormone needed for people with diabetes) – bacteria are used as they reproduce very quickly rather than having to extract the insulin from other humans / animals Higher Tier

Vectors A useful gene is isolated from one organism’s genome using enzymes and is inserted into a vector The vector is usually a virus or a bacterial plasmid (a small ring of DNA) depending on the type of organism that the gene is being transferred to When the vector is introduced to the target organism the useful gene is inserted into its cell(s) Higher Tier

Insulin Production

Practice Questions B. thuringlensis is a species of bacteria which produces a crystal protein, which is poisonous to insects when eaten. Some crop plants including cotton and potatoes have been genetically engineered to produce the crystal protein. Explain how the enzymes would be used to make a cotton plant that can produce the crystal protein Suggest a benefit of this in the crop plant

Answers B. thuringlensis is a species of bacteria which produces a crystal protein, which is poisonous to insects when eaten. Some crop plants including cotton and potatoes have been genetically engineered to produce the crystal protein. Explain how the enzymes would be used to make a cotton plant that can produce the crystal protein – enzymes cut the crystal protein gene and inserted into a vector which is then introduced into the target plant Suggest a benefit of this in the crop plant – if insects ate the crop they will be poisoned so less crop will be eaten and yields increase