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Flashcards in Genetic Engineering Deck (17):

What is Genetic Engineering and what can it also be known as?

Genetic Engineering the combining of two of more different organisms to create recombinant DNA. (Deliberate modification of the characteristics of an organism by manipulating its genetic material)


What is a key aspect of Genetic Engineering

A key aspect is that genetic code is universal and organism are made with A, T, G, C but with different sequences hence can be paired by complementary base pairing


What are the two enzymes to make recombinant DNA

1. Restriction enzyme acts as chemical scissors to cut a particular DNA sequence and the sequence that it cuts is called a restriction site. Each restriction enzyme is also specific for a particular DNA sequence. GOTTA USE THE SAME ONE BRO
2. Ligase acts as glue and glued DNA back together


What are uneven DNA sequences called

Sticky ends


What are the steps of making recombinant DNA

DNA is isolated, restriction enzyme cuts DNA into fragments, another DNA fragment is cut using the same enzyme, the two fragments are stuck together by complementary base pairing. DNA Ligase pastes the sugar-phosphate backbones and recombinant DNA is made.


Why is plasmid so unique in genetic engineering

A plasmid typically contains an antibiotic resistance gene, which allows bacteria to survive in the presence of a specific antibiotic. A bacteria that took up the plasmid can be selected on nutrient plates containing the antibiotic. Bacteria without a plasmid will die, while bacteria carrying a plasmid can live and reproduce. Each surviving bacterium will give rise to a small, dot-like group, or colony, of identical bacteria that all carry the same plasmid.


What makes bacterium a good factory for insulin

Genetic structure - bacterial chromosome, plasmid (which are easy to move in and out of cell)

Bacteria are unicellular and they reproduce asexually which means quick clones (important if you want factories)


What are the steps of making insulin through genetic engineering

First the plasmid from bacterium and insulin DNA from human cell is isolated, the plasmid is then cut with restriction enzyme and the same restriction enzyme is used to cut the human DNA insulin gene. The two are combined with complementary base pairing and ligase attaches them together. the recombinant DNA is then put back into the bacterium by TRANSFORMATION. The bacterium reproduces and insulin protein is isolated from the cloned bacterium


What is cloning

Cloning is the process of making organisms that are exact genetic copies. Clones are organisms that are exact genetic copies and every bit of their DNA is identical.


What are the two ways of cloning an organism in a lab

Artificial embryo twinning and somatic cell nuclear transfer


What is artificial embryo twinning

Artificial embryo twinning mimics the natural process of twins. In nature, twins are created when the resulting fertilised egg, zygote tries to divide into a two-called embryo. When they separate each cell continues dividing on its own. In AET the same approach is taken but occurs in a Petri dish instead and manually separating a very early embryo into individual cells. Resulting embryos are placed into a surrogate mother


What is somatic cell nuclear transfer

Nucleus that contains organisms DNA of a somatic cell is removed, egg cell nucleus is removed and discarded. Nucleus from somatic cell is transferred into egg cell. Cell division is stimulated. Implant embryo into a surrogate mother.


What Is unique about SCNT

Egg cell nucleus is replaced by nucleus from somatic cell which contains two complete set of chromosomes.


Is cloning an organism the same as cloning a gene

No, cloning an organism is creating an exact genetic copy of the whole organism
Cloning a gene is simply isolating and make exact copies of a specific gene in the organism.


Why cloning?

Cloning animal models of disease
Making stem cells
Copies of animals with desirable traits
Bringing back endangered/extinct species


What are the pros and cons of cloning

-all new plants are genetically identical which means they will all have desired characteristics
- organism can be reproduced quicker especially when they are normally slow or difficult to breed

- if clone is susceptible to disease of changes in environment then all clones will be susceptible
- leads to less variation and less opportune to create new varieties in the future


How do you clone plants by tissue culture

1. Tissue sample scraped from parent plant
2. Sample placed in agar growth medium containing nutrients and auxins
3. Sample develop into tiny plantlets
4. Plantlets planted into compost