Unit 2 Key area 7 Flashcards
State two methods of improving wild strains of microorganisms?
- Recombinant DNA technology
- Mutagenesis
State what is meant by mutagenic agents?
Mutagenic agents are mutagenic chemicals and radiation that increases the rate of mutation allowing for new improved strains of a microorganism to be produced.
What can be used as a vector in recombinant DNA technology?
- recombinant plasmids
- artificial chromosomes
State what is meant by the term vector, in DNA technology?
In DNA technology a vector refers to a DNA molecule that is used to carry foreign genetic information into another cell. Both plasmids and artificial chromosomes can be used as vectors during recombinant DNA technology
In which circumstances would the use of an artificial chromosome be preferential to the use of a plasmid as a vector and explain your answer?
In the case where large fragments of foreign DNA are required to be inserted.
Describe the role of restriction endonucleases in recombinant DNA technology?
Restriction endonucleases cut open plasmids and cut specific genes out of chromosomes leaving behind sticky ends.
Complementary sticky ends are produced when identical enzymes are used to cut into the chromosome and plasmids. The enzyme ligase then seals the required gene into the plasmids
State the four key features present within artificial chromosomes, and recombinant plasmids?
- Restriction sites
- origins of replication
- Regulatory sequences
- selectable markers
Describe the role of restriction sites in recombinant DNA technology?
Restriction sites contain “target sequences” of DNA where specific restriction endonucleases are told to cut.
State the role of regulatory sequences in recombinant DNA technology?
Regulatory sequences control gene expression
Describe the role of the origin of replication in recombinant DNA technology?
The origin of replication allows the recombinant plasmids or artificial chromosomes to self replicate
Describe the role of the selective markers in recombinant DNA technology?
The selective markers are the genes present in the vector that will ensure that only the vectors that have taken up the required gene will survive the selective agent e.g antibiotics.
Explain a common safety mechanism that is used in recombinant DNA technologies?
It is common to insert genes into the microorganism that prevents it from being able to survive in an external environment.
Explain one of the key issues of using recombinant plasmids in bacteria and how we can fix this problem?
When we use recombinant plasmids on animal or plant genes the DNA may be folded incorrectly. To counteract this we can use recombinant yeast to prevent the genes from being folded incorrectly.
