Gene Technology Flashcards
Gene technology uses what? What are the 3 ways that they can be produced
DNA fragments
Can be produced using…
Reverse transcriptase
Restriction endonuclease
PCR
What is gene technology and examples. What are these techniques used for
All the techniques that can be used to study genes and their function
Examples…
Polymerase chain reaction (PCR)
In vivo gene cloning
DNA probes
Used for many things including DNA fingerprinting and diagnosing diseases
What are palindromic sequences of nucleotides
Sequences which consist of antiparallel base pairs
What does restriction endonuclease do
Recognises specific palindromic sequences (known as recognition sequences) and cut the DNA at these places. Different RE recognise different recognition sequences as the shape of the recognition sequence must be complementary to the enzymes active site. If recognition sequences are present at either side if the fragment, they cut here. The DNA sample is incubated with the specific RE and the fragment is cut out via a hydrolysis reaction. Sticky ends can be left, which can join the fragment to other pieces of DNA that has sticky ends with complementary sequences
What does reverse transcriptase do
Only 2 copies of gene in cells, but many complementary mRNA molecules. These used as templates to make complementary DNA (cDNA). mRNA isolated from cells, mixed with free nucleotides and reverse transcriptase
What is a sticky end
A small tail of unpaired bases at each end of the DNA fragment
What is the polymerase chain reaction used for
To make millions of copies of a fragment of DNA
What are primers
Short pieces of DNA that are complementary to the bases at the start of the fragment you want
What does DNA polymerase do
Creates new DNA strands
What is genetic engineering
The manipulation of an organisms DNA, also known as recombinant DNA technology
Transformed organisms are also known as….
Genetically engineered or genetically modified organisms
How can transformed organisms benefit agriculture
Can give higher yields or are more nutritious. Means plants can be used to reduce risk of famine and malnutrition. Crops can have pest resistance so fewer pesticides are needed. This reduces cost and environmental problems. Eg golden rice is a variety of transformed rice, contains 1 gene from maize plant and one from soil bacterium. Enable rice to produce beta-carotene. These are used in body to give vitamin A. Being developed in areas of world where vitamin A deficiency is a large problem
How can transformed organisms benefit industry
Industrial processes often use biological catalysts (enzymes). These enzymes can be produced from transformed organisms so they can be produced in large quantities for less money. Eg rennin is enzyme used in cheese making, used to make rennet (Substance made in cows stomachs). Can now be made from transformed organisms so can be made in large quantities cheaply and no harm to cows
How can transformed organisms benefit medicine
Many drugs and vaccines produced by transformed organisms so can be produced quickly, cheaply and in large quantities. Eg insulin (used to treat type 1 diabetes) used to come from animals. This insulin wasn’t human insulin so didn’t work as well. Human insulin now made from transformed organisms using a cloned human insulin gene
What are the concerns about the use of genetic engineering to agriculture
Farmers might plant only one type of transformed crop (monoculture) makes whole crop vulnerable to disease as plants genetically identical
Some people concerned about superweeds, weeds that are resistant to herbicides. These could occur if transformed crops interbreed with wild plants
What are the concerns of genetic engineering to industry
Without proper labelling, some people think they won’t have a choice about whether to consume food made using genetically engineered organisms. Some are worried that the process used to purify proteins could lead to the introduction of toxins into food industry
What are the concerns of genetic engineering to medicine
Companies who own genetic engineering technologies may limit the use of technologies that could save lives. Some worry this technology could be used unethically eg make designer babies
What do humanitarians think about genetic engineering
crops could be produced that help reduce risk of famine and malnutrition
Transformed crops could be used to produce useful pharmaceutical products eg vaccines which could make drugs available to more people
Medicines could be produced more cheaply so more can afford them
What do environmentalists and anti-globalisation activists think about genetic engineering
Environmentalists oppose recombinant DNA technology as they think it could potentially damage environment. Eg transformed crops could encourage farmer to carry out more monoculture, decreasing biodiversity. Also fears of superweeds
Anti-globalisation activists think a few large biotechnology companies control some forms of genetic engineering. As the use of this technology increases the companies get bigger and more powerful. May force smaller businesses out of business
How are anti-globalisation activists
People who oppose globalisation (growth of large multinational companies at the expense of smaller ones)
What are genomes
All the genetic material in an organism
What are repetitive non-coding base sequences
Base sequences that don’t code for proteins and repeat next to each other over and over
How can genetic fingerprinting be used to determine genetic relationships?
We inherit the repetitive, non-coding base sequences from parents. Roughly half of sequences come from each parent. Means the more bands on genetic fingerprint that match, the more closely related 2 people are.
How can genetic fingerprinting be used to determine genetic variability within a population?
The greater the number of bands that don’t match, the more genetically different people are. Means you can compare number of repeats at several places in the genome for a population to find out how genetically varied that population is eg the more the number of repeats varies at several places, the greater the genetic variability
Genetic fingerprinting can be used in forensic science. Explain…
Used to compare samples of DNA collected from crime scenes (eg DNA from hair, blood, skin cells)
Genetic fingerprinting can be used in medical diagnosis. Explain…
A genetic fingerprint can refer to a unique pattern of several alleles. Can be used to diagnose genetic disorders and cancer. Useful when the specific mutation isn’t known or where several mutations could have caused the disorder as it identifies a broader, altered genetic pattern.
Example- PGH screens embryos created by IVF for genetic disorders before they’re implanted into uterus. Faulty regions of parents DNA used to produce genetic fingerprints which are compared to the genetic fingerprint of the embryo. If fingerprints match, embryo has inherited disorder eg cystic fibrosis