B1 Genetic Engineering Flashcards
Describe the basic idea of genetic engineering.
Transfer a gene from the genome of one organism to the genome of another. This gives the organism that receives the gene new and useful characteristics
How does genetic engineering work?
Because all organisms use the same molecule (DNA) to store their genetic material
A gene that helps fish to survive in cold water has been inserted into tomato plants. Why?
To help the plants survive at low temperatures
The gene for the human insulin protein has been inserted into bacteria. Why?
The bacteria are grown in large numbers to produce insulin for the treatment of diabetes.
Describe in detail how genetic engineering is done.
A useful gene is isolated from an organisms genome using enzymes.
The gene is then replicated to produce lots of copies.
Each copy is inserted into a vector.
The vectors are then mixed with other cells (eg bacteria)
Most of the cells don’t take up the vector and the desired gene, so the cells that have been modified need to be identified and selected.
The selected cells are then allowed to replicate - each new cell will contain the desired gene and produce the protein it codes for.
What is a vector?
A vector is usually a virus or bacterial plasmid depending on the type of organism that the gene is being transferred to.
Why are vectors used?
The idea is that the vectors (containing the desired gene) will be taken up by the cells, which will become genetically modified.
Why are plasmids good vectors to use in the genetic engineering of bacteria?
Because they are separate to the main chromosomal DNA and naturally pass between bacterial cells.
What can genetic modification be used for in crops?
Crops can be genetically modified to be resistant to herbicides.
Making crops herbicide resistant means farmers can spray crops to kill weeds without affecting the crop.
This can increase crop yield, helping us to produce more food.
What can genetic modification be used for in medicine?
Genetically engineered bacteria can be used to produce insulin.
Researchers have also managed to transfer human genes that produce useful proteins into sheep and cows (eg human antibodies used in therapy for illnesses like arthritis). These proteins can then be extracted from the animals (eg from their milk)
