Biotechnology Unit 3 Flashcards
What is genetic engineering?
is the direct manipulation of an organism’s DNA which alters the organism’s phenotype in some way. GE could be changing, adding, or deleting a base pair or recombining DNA between different species
Why can Genetic engineering exist ?
there is only one language of life
A,C,T, AND G
What are the most important enzymes to perform gene splicing or genetic engineering ?
restriction enzymes
What do restriction enzymes accomplish in the process of genetic engineering?
step 1: they scan the length of the DNA molecule and stop to cut the molecule only at its particular cut site
step 2: a staggered cut exposes short, single-stranded regions of the molecule, which are known as sticky ends
step 3: sticky ends produced by the same restriction enzyme can be spliced together. The sticky ends produced as a result of the staggered cut by the RE allow complementary regions in the sticky ends to base pair up.
- END RESULT: recombinant DNA or transgenic DNA or genetically modified DNA
What are restriction enzymes?
Restriction enzymes or endonuclease, are naturally occurring enzymes isolated primarily from bacteria that can be used to cut DNA molecules into precisely sized fragments.
Define gene splicing (recombinant DNA)
what is the process?
The joining of the genes of two or more organisms to produce recombinant (recombined) genetic
material
- same restriction enzyme used to cut BOTH the donours DBA and the recipient’s DNA
- using the same restriction enzyme on both individuals serves to create complementary “ sticky ends” where the DNA’s were cut
- to “Glue” the sticky ends together, the concept of base pairing is once again used. Ligase, found in the nucleus during replication, are the enzymes used to base pair the sticky ends
what are the pros of Genetic engineering?
- efficient means of producing substances such as vaccines, hormones, food (crops)
- meets the demands of a growing human population
- cures genetic diseases using gene therapy
- pest control
- cleaning up oil spills
what are some cons of genetic engineering?
- since governments are allowing GE companies to patent their genetically modified DNA, this allows GE companies to own living organisms e.g rice, plants, humans?
- misuse of knowledge leading to biological warfare
- transfer of seeds to neighbouring crops (gene flow)
What is reproductive cloning and what is the abbreviation for it?
cDNA
- is the replication of full organism, all of whom are genetically identical to the parent, the intent is to mass produce
What was the obstacle that scientists needed to overcome to make cloning mammals possible?
- how to unspecialized
specialized cells - cell specialization prevents cloning of higher order animals because those cells are too specialized
Draw out #11 to understand Gene splicing
What was the obstacle that scientists needed to overcome to make cloning mammals possible?
- how to unspecialized
specialized cells - cell specialization prevents cloning of higher-order animals because those cells are too specialized
Draw on#12 on white board demonstrating cloning
During the process of cloning the offspring mammal will give all its nuclear DNA from ________, but all its mtDNA (mitochondria DNA ) from ______, this the offspring has a majority of traits from species?
- species that somatic cell with a nucleus
- The species that had its nucleus removed and donated its mitochondria
- the offspring has the majority traits from species who donated nucleus since DNA information is found there
What are the pros to reproductive cloning?
- herd improvement
- prevent diseases and offset world hunger
- improve the environment affect by factory farming.
- save endangered species and build their opportunities.
what is therapeutic cloning?
- cloning organs or tissues using stem cells (unspecialized cells)
- no organisms are produced
-An embryo is made to have the same genetic information as the patient and so the stem cells from it wouldn’t be rejected by the patients’ body.
Describe therapeutic cloning.
- Remove body (somatic) cells from a donor. Leave its nucleus intact.
Starve this cell so all its genes are turned off. (Unspecialized a specialized cell) (2n). - Remove egg cells from the donor (discarded embryos). Remove the nucleus and all genetic material) from egg cell (On).
- Inject somatic cells into the egg (somatic cell nuclear transfer).
- Allow mitosis to occur.
- Add proteins that turn certain genes on and others off.
- Grow your own tissues or whole organs with no fear of organ rejection
what are some examples of embryonic stem cells (unspecialized cells )
- blastocyst
- umbilical cord/placenta
- sperm cell prior to spermatogenesis
what are some examples of adult stem cells (unspecialized cells)
- bone marrow
- blood
- brain
- spinal cord
- intestines
-muscles - skin
Describe the process of Polymerase Chain Reaction. (PCR)
- polymerase chain reaction (PCR) is a common method of creating copies of specific fragments of DNA. PCR rapidly amplifies a single DNA molecule into billions of copies
- In one application of the technology, small samples of DNA, such as those found in a strand of hair at a crime scene, can produce sufficient copies to carry out forensic tests
What is Gel Electrophoresis + PCR? describe the process.
Label the parts of the gel electrophoresis
describe the base substitution: silent mutation.
usually occurs when the last base in the codon is substituted for another; resulting in no change in amino acid sequence
Describe the base substitution : nonsense mutation
usually occurs when the first base in codon is substituted for another
- premature stop- codes for no protein
Describe the base substitution : missense mutation
usually occurs when middle base of codon is substituted for another.
- Change in AA sequence resulting in wrong protein being produced
ex. sickle cell anemia
What is Addition or deletion in a gene sequence?
addition or deletion of N-base or codons. This shifts the frames (or codons) from that point onward in the gene.
total number of N-bases increases (if insertion) or decreases (if deletion)
- results in either missense or nonsense mutations, never a silent mutation
- change in AA sequence results in wrong protein or no protein being produced
- change all the way through the sequence
What is somatic (body) cell mutation?
not passed on to the next generation. Remain with individual because mutation is in the individuals somatic cells
- affected individual can have normal children; mutation is not in the cells of the individuals gonads
Gamete (sex cell) mutations?
mutation occurred in the gametes during meiosis. This will be passed on to the offspring and the mutation will be present in every cell of the offspring due to mitosis.
