Objectives 4.4.7 through 4.4.13

Stephanie AmatuzzoMorgan Anderson

Alexis BowdenOlivia Freeman

Objective 4.4.7 State that, when genes are transferred

between species, the amino acid sequence of the polypeptides translated from them is unchanged because the genetic code is universal

Terms Vector: a bacteriophage, plasmid, or other agent that

transfers genetic material from one cell to another. Plasmids: circular bits of genetic material carrying 2 to

30 genes Host Cell: A cell that has been introduced with DNA (or

RNA), such as a bacterial cell acting as a host cell for the DNA isolated from a bacteriophage.

Restriction Enzymes: An enzyme that catalyzes the cleavage of DNA at restriction sites, producing small fragments used for gene splicing in recombinant DNA technology and for chromosome mapping.

Terms DNA Ligase: Enzymes the form bonds

attaching the DNA fragments of the lagging strand to become one strand.

Sticky Ends: The end of unevenly cut DNA, easily matches with complimentary base over hangEX. 5'-ATCTGACT GATGCGTATGCT-3'

3'-TAGACTGACTACGCATACGA-5'

Objective 4.4.7 Genetic Engineering: Refers to the

deliberate manipulation of genetic material.

The genetic code is universal Possible to move genetic material

between species

Objective 4.4.7 For every organism the same RNA

codon codes for the same amino acid in an mRNA strand for every species› E.g. UUU,UUC both code for the amino acid

phenylalanine› Makes it possible to transfer genetic

material from one species to another

Objective 4.4.8 Outline a basic technique used for

gene transfer involving plasmids, a host cell(bacterium, yeast, or other cell), restriction enzyme(endonucleases) and DNA ligase› Restriction enzymes(endonucleases) –

used to cut a desired section of the DNA

Objective 4.4.8 Insulin

› Gene which codes for insulin is put into a plasmid

› That plasmid is then put into a host cell(bacterium)

› That host cell can now synthesis insulin to be collected and used by diabetics

4.4.8 More in depth

› mRNA that codes for insulin is taken from a human pancreatic cell that produces insulin

› DNA copies are next made from the mRNA using the enzyme reverse transcriptase

› Extra guanine nucleotides are added to create sticky ends

› A selected plasmid is cut using restriction enzymes(cut the DNA at specific base sequences)

› Extra cytosine nucleotides are added to create sticky ends

4.4.8› Plasmid and gene are mixed together› The cytosine and guanine nucleotides

match together› DNA ligase makes sugar phosphate bonds› Plasmids with human insulin gene is mixed

with host cells› Host cell takes in the plasmid and starts

producing insulin› Insulin is collected and purified

Objective 4.4.9 State two examples of current uses of

genetically modified crops or animals

Objective 4.4.9 Tomatoes

› Altered to stay fresher longer – “Flavr Savr” by adding a gene that blocked the enzyme that caused rotting

Objective 4.4.9 Bt Corn

› Bacillus thuringiensis has been incorporated into the DNA of the corn, corn now produces a toxin that makes them insect resistant

Objective 4.4.10 Discuss the potential benefits and

possible harmful effects of one example of genetic modification

Bt Corn – Bacillus thuringiensus(a bacteria) produces a protein that is toxic to specific insects Benefits

› Less checking for ECB-European Corn Borers

› Damage caused by ECB is reduced, saving farmer money

› Less insecticides needed, meaning less impact on environment and lower health risks for workers

Weaknesses› Kills unnecessary

insects

Objective 4.4.11 Define clone

› Clone – a group of genetically identical organisms or a group of cells derived from a single parent cell

› http://www.brainpop.com/science/cellularlifeandgenetics/cloning/

Objective 4.4.12 Outline a technique for cloning using

differentiated animal cells

4.4.12 Dolly

› Udder cells were taken from a donor sheep› Cells were cultured› An unfertilized egg was taken from another

sheep› Nucleus was removed from that egg› Egg cells were fused with the udder cells with

electricity› Cells became zygotes and then embryos› Embryos implanted into surrogate sheep› Resulting sheep was identical to the sheep

that donated the udder cells

Objective 4.4.13 Discuss the ethical issues of

therapeutic cloning in humans› Fears of it leading to reproductive cloning› Use of embryonic stem cells involves the

creation and destruction of human embryos

› Embryonic stem cells are capable of many divisions and may turn into tumors

Works Cited "IB Guides." IB Biology Notes. Web. 08 Mar. 2012.

<http://www.ibguides.com/biology/notes/genetic-engineering-and-biotechnology>.