Genetic Engineering And Biotechnology

Question 1

What is the basis of genetic engineering? (3)

Answer 1

• Genetic engineering involves manipulation, introduction, or deletion of genes forms for practical purposes
• DNA technology can be used to cure diseases, treat, genetic disorders, improve crops, and other such things to improve the lives of humans
• Example: making insulin to manage diabetes

Question 2

Restriction enzymes (3)

Answer 2

Bacterial enzymes, a.k.a. restriction endonucleases used to cut DNA molecules that don’t belong to them into more manageable pieces
They produce fragments with sticky ends or blunt ends
Can be used to isolate a specific gene

Question 3

Blunt ends

Answer 3

After the restriction enzyme cuts the DNA, they have no overlap

Question 4

Sticky ends

Answer 4

After the restriction enzyme cuts the DNA, they have complementary overhangs

Question 5

What is a cloning vector? (2)

Answer 5

A carrier that is used to clone a gene and transfer it from one organism to another
Many bacteria contain a cloning vector called plasmid

Question 6

Why are bacterias used to introduce the genes of interest?

Answer 6

Bacterias are much better and quicker at making biological valuable products when compared to chemical means since they can reproduce and multiply rapidly

Question 7

What are genes of interest?

Answer 7

A gene of interest is a gene that a scientist may want to study to learn more about the genes function, structure or sequence
(What it does, what it looks like, DNA coding)

Question 8

Gene transfer experiment procedure

Answer 8

1. A plasmid is isolated from a bacterium
2. Using restriction enzyme the plasma is then cut and a donor gene (a specific gene isolated from another organism that is of interest) is spliced into
3. The plasmon it is then return to the bacterium where is replicated as the bacterium divides (binary fission). This makes copy of the donor gene.
4. Once many copies of the donor gene has been made plasmid with the donor gene can be isolated from the bacteria. Each plasmon now contains a gene clone. (Exact copy of the gene)

Question 9

Transplanting genes - insulin

Answer 9

Insulin is a hormone produced by the pancreas that helps to lower blood glucose levels when they are too high. Diabetics don’t produce enough insulin and have to take regular injections.
A large volume of insulin can be made for humans by inserting the human gene for insulin into bacteria
These bacteria that receive the insulin Jean will make insulin as long as the gene isn’t turned off

Question 10

Step 1 of gene transfer

Answer 10

Transferring the genes:
Isolating a gene - the restriction enzyme is used to cut the human DNA into many pieces. The pieces of human DNA are spliced into plasmids to create a genomic library.
Ex: Some of the plasmid will contain a DNA fragment that has the gene clone for human insulin.

The restriction enzymes that cut the gene and plasmid allows the two pieces of DNA to find each other with the help of an enzyme called ligase (glue) and they fused to become a Modified vector
* the restriction enzyme must be the same time one used on the plasmid and the gene of interest*

Question 11

Step two of gene transfer

Answer 11

Producing recombinant DNA - a combination of DNA from two or more resources is called recombinant DNA. Inserting a donor gene like the human gene for insulin into a cloning factor like a bacterial plasmid results in a recombinant DNA molecule. When the plasmid is removed from the bacterial cell and the insulin gene is inserted into the plasmid, recombinant DNA is created.

Question 12

Step 3 of gene transfer (2)

Answer 12

Cloning the DNA - the plasmid that now contains a common in DNA is inserted into the host bacterium.
The transgenic bacterium is now placed in a nutrient medium, where it can grow and reproduce inside each bacterium.
Ex: The plasmid is copied many times, making clones of the gene for insulin thousands of bacteria are produced quickly through cell division, resulting in thousands of bacterial that carry the gene for insulin .

Question 13

What is a transgenic organism

Answer 13

a host that receives the recombinant DNA

Question 14

How to make sure that the cells pick up plasmid (2)

Answer 14

Screening process - antibiotic selection
The plasmid is being used carries a selectable marker, which is usually a gene that codes for antibiotic resistance

The bacteria are grown in the presence of antibiotics, bacteria with plasmid will be able to live and grow, whereas back to year, without plasmids will die.

Question 15

Explain the final steps to harvest plasmids from the bacteria (2)

Answer 15

The bacteria are lysed (The cell membrane is broken open) and the plasmids are separated from the bacterial DNA using acidic solution (low PH) which is high in salt (because plasmid DNA can with stand these conditions, but regular DNA cannot)

Finally, the plasmids are separated from all the other cell parts using centrifugation

Question 16

Why is E. coli great for recombinant cloning? (3)

Answer 16

The best host is bacteria, especially E. coli because they can multiply quickly
If E. coli contains the gene of interest, every time a duplicate itself, the new bacteria will have the gene of interest too
Upon knowing a lot of, it’s genetic and bio chemical mechanism, scientist can treat E. coli with chemicals to make it easier for them to pick up the plasmid dna (osmotic pressure’s or plasmids with salt)

Question 17

What can recombinant cloning be used for? (3)

Answer 17

Biopharmaceuticals (create insulin, treat, strokes, prevent blood clots)
Gene therapy, which is when normal jeans are transplanted into cells that are missing or defective to correct genetic disorders (ex: can decrease the time it takes lungs to deteriorate in cystic, fibrosis patients)
Can be used to create vitamin C

Question 18

What is DNA fingerprint?

Answer 18

A DNA fingerprint is a pattern of bands made up of specific fragments from an individuals DNA
They appear as fuzzy bands of stain arranged in columns

Question 19

What is DNA fingerprinting used for? (3)

Answer 19

How close people are related, ancestry
Evolution of species, and how close to species are related
Compare samples of blood or tissue found at a crime scene with a suspects blood sample

Question 20

What is RFLP

Answer 20

Restriction fragment length polymorphism prepares DNA fingerprint by extracting the dna from a specimen of blood and cutting it into fragments using multiple restriction enzymes

The number of fragments and length of each fragment varies from person to person

Question 21

What is gel electrophoresis?

Answer 21

Used for RFLP analysis, gel electrophoresis, separate nucleic, acids or proteins, according to their size and charge

Question 22

Gel electrophoresis procedure

Answer 22

• Samples of DNA that are going to be compared are being placed in Wells made on the gel
• electric current runs through the gel for a given period of time (important)
• DNA fragments (negatively charged) migrate towards the positive charge, and of the gel: smaller, DNA fragments= migrate faster allowing separation by size
• separated DNA fragments. Or split into chains and blot it onto filter paper
• Probes (radioactive segments of DNA that are complementary to the segments being compared) are added to the filter paper
  -Probes bind the complementary fragment, forming visible bands when exposed to photographic film
• Expose film reveal a DNA fingerprint which can be analyzed visually or by a computer

Question 23

What is a polymerase chain reaction (PCR)?

Answer 23

PCR can be used to quickly make many copies of selected segments of the DNA
- DNA amplification :
Amplify anyone’s genes
Does it require living cells (sample can be old)

Question 24

What does PCR require?

Answer 24

PCR requires:
- a DNA molecule or a fragment of DNA
- A supply of the four nucleotides (cytosine thymine guanine and adenine)
- DNA polymerase (the enzyme involved in DNA replication, the matching pair to build)
- Primers (an artificially made single-stranded sequence of DNA needed for initiation of replication)

Question 25

What is DNA polymerase?

Answer 25

The enzyme involved in DNA replication, the matching pair to build

Question 26

What are primers? (3)

Answer 26

An artificially made single-stranded sequence of DNA needed for the initiation of replication
“ starter blocks” for the growing chain of nucleotides made by the DNA polymerase
Synthetic regions designated to recognize ends of genes

Question 27

What does PCR involve?

Answer 27

Using repetitive steps of DNA replication:
1. Denaturation
2. Annealing
3. Elongation.

Question 28

Step one of polymerase chain reaction

Answer 28

Denaturation:
- All of the four components needed for PCR are added together and placed in a thermal cycler
- Separates the complementary strand of DNA using heat specifically a temperature of about 95°C

Question 29

Step two of polymerase chain reaction

Answer 29

Annealing:
-Thermal cycler turn the temperature down to about 50°C
-Allows the primaries and DNA strand to find each other

Question 30

Step three of polymerase chain reaction

Answer 30

Elongation:
-Thermal cycler is temperature goes to about 72°C to activate DNA polymerase
-DNA polymerase locate a Primer attached to a single DNA strand, and begins to add complementary nucleotides onto the strand
-allows the DNA polymerase to make a new strand

Question 31

PCR cycles

Answer 31

The number of cycles corresponds to how many times the process will go on
The number of cycles will tell you how many strands are made (2 to the power of #)

Question 32

Producing pharmaceutical products with DNA technology

Answer 32

Some proteins are made much more inexpensively using DNA technology:
Insulin, erythropoietin, human growth hormone

Question 33

Recombinant vaccination

Answer 33

A type of subunit vaccination
It involves putting the surface proteins gene from the virulent virus into another virus or organism the second organisms to create the protein, but will not give the patient the disease

Question 34

Genetically engineered vaccines

Answer 34

The envelopes are sufficient to produce the important antibodies in the host organism
Scientist can genetically introduce the jeans responsible for coding the envelope proteins into organisms that don’t even have to be viral in nature
These are subunit vaccinations (taking a part of the proteins)

Question 35

Subunit vaccinations

Answer 35

Subunit vaccination, take bacteria that are produced in large quantities and administer them to hosts

Question 36

Bioremediation

Answer 36

Process of using micro organisms to clean up toxic sites such as oil spills:
Soil, bacteria, capable of degrading, xenobiotic chemicals into harmless products that could be used for energy

Question 37

Pseudomonas bacteria (2)

Answer 37

Good at breaking down, xenobiotic compounds (Can detoxify more than 100 different compounds)
Able to do this because they carry genes that code for enzymes which are able to break down toxic compounds

Question 38

Problems with bioremediation (3) + solution (2)

Answer 38

Problem:
1. Maybe very slow
2. Back to your may not be able to degrade all of the chemicals.
3. Chemicals may actually kill the bacteria themselves at high concentration

Solution:
Super bug using genetic engineering as degraded detective enzymes are usually located in plasmid = Scientist could control which toxic chemicals are broken down

Question 39

CRISPR

Answer 39

Genetic engineering works by removing a deleterious gene. CRISPR Cas-9 move the DNA sequence, and then after the target gene is removed the DNA will repair itself without the gene of interest. When deleterious gene is removed, it can even be then replaced with a desired gene.