ChApter 3- Genetics- Genetic Engineering And Biotechnology

Question 0

When is PCR useful?

Answer 0

When only a small amount of DNA is available eg crime scenes samples of blood, semen or tissue

Question 1

What do PCR do?

Answer 1

It’s a way of producing large quantities of specific target sequences of DNA

Question 2

What are the 3 steps of PCR?

Answer 2

1) denaturation- DNA sample is heated to separate into 2 strands
2) annealing- DNA primers attach to opposite ends of the target sequence
3) elongation- a heat tolerant DNA polymerase (Taq) copied the strand

Question 3

One cycle of PCR results in what?

Answer 3

2 identical copies of DNA

Question 4

What is gel electrophoresis?

Answer 4

A technique which is used to separate fragments of DNA according to size

Question 5

How are DNA chopped on gel electrophoresis?

Answer 5

With enzymes

Question 6

What is the process of gel electrophoresis?

Answer 6

1) samples of DNA are placed in wells of agarose Jel
2) gel is placed in buffering solution and an electrical current is passed across the gel
3) DNA, being negatively charged (due to phosphate) moves to a positive terminus (anode)

Question 7

How does gel electrophoresis separate DNA according do size

Answer 7

Smaller fragments are less impeded by gel matrix and moves faster so fragment are separated according to size

Question 8

30 cycles of PCR can result in a yield of how many copies?

Answer 8

1,073,741,82

2^30

Question 9

How can size be calculated in gel electrophoresis?

Answer 9

Size can be caliualted in kilobase by comparing it against a known jndustry standard

Question 10

Draw the process of gel electrophoresis

Question 11

What is gel electrophoresis used for when separated into sizes?

Answer 11

Process of matching an unknown sample of DNA which a known sample to see if they correspond– it’s called DNA profiling

Question 12

If after gel electrophoresis the pattern of bands formed by 2 samples are identical what does it mean?
If patters are similar what does it mean for the 2 individuals?

Answer 12

If identical= same person

If similar= related

Question 13

When can DNA profiling be used

Answer 13

In paternity suits when the identity of someone’s biological father is needed of crime scenes collect blood etc

Question 14

What can gel electrophoresis helpful in the environment

Answer 14

Use DNA samples taken from birds etc to see which animals are related etc

Question 15

How does gel electrophoresis work in paternity testing?

Answer 15

Children inherit half of their alleles from each parents and thus should posses a combination of parent alleles

Question 16

How does gel electrophoresis work in forensic investigation?

Answer 16

Suspect DNA should be a completes tvh with a sample take from a crime scene if a conviction is to occur

Question 17

What is the human genome project?

Answer 17

Set out to sequence the complete human genome

Question 18

What is a genome?

Answer 18

Is a catalogue of all the bases it possesses (3 billion base pairs ~25,000 genes)

Question 19

What are 4 outcomes of the completed human genome project?

Answer 19

Mapping, screening and ancestry and medicine

Question 20

The 4 outcomes mapping,screening and ancestry and medicine- explain how there useful?

Answer 20

Mapping; know the number,location and basic sequence of human genes
Screening: allowed for the production of specific gene probes to detect sufferers and carriers of genetic disease conditions
Ancestry: gives us improved insight into the origins,evolution and historical migratory patterns of humans
Medicine: discovery of new proteins and their function, we can develop improved treatments (pharmacogenetics, drug design)

Question 21

What is gene transfer?

Answer 21

The technique of taking a gene out of the organism (donor organism eg fish) and placing it j to a another organism (eg tomato) made the tomato more resistant to cold

Question 22

The genetic code is universal how is that useful in gene transfer?

Answer 22

Means every living organisms has the same codons (A,T,C,G) for the same amino acids therfore means genetic information from 1 organism can be translated by another

Question 23

What is an example of gene transfer and the process?

Answer 23

Make human insulin

1) plasmid is remove from host
2) plasmid Is cut open using a restriction endonuclease
3) gene is pasted into plasmid using DNA ligase–> plasmid is now called a recombinant plasmid and can be used as a vector, a tools for introducing new gene into organisms genetic make up
4) finally vector is placed inside host bacterial and the bacterium is give idea conditions to grow and proliferate

Question 24

Where is the bacterium put once the new vector is in it?

Answer 24

A bioreactor, a vat of nutritious liquid kept at a warm temperatures

Question 25

The process of gene transfer has allowed e.coli do successfully do what?

Answer 25

Make human insuline

Question 26

Why is it better to use gene transfer for insulin rather than from pigs or cow carcasses?

Answer 26

Causes allergy problems and the other way foesnt

Question 27

What are 2 examples of current uses for modified crops?

Answer 27

1) engineering crops to extend shelf life of fresh produce

2) engineering crops to protect itself from insects

Question 28

Give an example of an engineered crop to extend shelf life

Answer 28

Tomatoes (flavr savr) hve been engineered to have an extended keeping quality by switching off the gene for ripening and thus delaying the natural process of softening fruit

Question 29

Give example of engineering crops to protect insects

Answer 29

Maze crops (Bt corn) have been engineered to be toxic to the corn borer by introducing a toxin gene from a bacterium (bacillus thurgrienis)

Question 30

Give 2 examples of uses today of genetically modified animals

Answer 30

1) engineering animals to enhance protein

2) engineering animals to produce desired products

Question 31

Give example of engineering animals to enhAnce protein

Answer 31

Sheep produce more woll when engineered with the gene enzyme responsible for the production of cysteine- main amino acid in the keratin protein of wool

Question 32

Give example of engineering animals to produce desired products

Answer 32

Sheep engineered to produce human alpha- 1- antitryspin in their milk can be used to help treat individuals suffering from hereditary emphysema

Question 33

What are potential benefits of Gentic modification?

Answer 33

1) GM crops will help farmers by improving food production
2) crops will produce there own pest- control which means fewer chemical pesticides w be used
3) used GMO’s to produce rare proteins for medication or vaccines could be less costly and produce less pollution that synthesising such proteins in labs
4) farmers have more control over what they crop or livestock
5) may help reduce hunger in developing nations by using pest resistance crops or GM plants which require less water

Question 34

What are the harmful effects of using genetic modification?

Answer 34

1) no one knows long term effects on wild
2) could change food chain/habitation
3) cod cause gene cross species– no one knows consequences
4) Bt crops which produce toxins could be harmful to humans
5) risk of allergy
6) decrease in biodiversity

Question 35

Define clone

Answer 35

Group of genetically identical organisms or a group of cells artificially derived from a single cell

Question 36

Draw a diagram for cloning using different animal cells

Answer 36

Kshowhjwhse

Question 37

What is the 7 step process for cloning?

Answer 37

1) somatic cell (non gamete cell) from udder was collected and cultures as nucleus removed
2) unfertilised egg collected from another sheep - nucleus removed
3) using a zap of electrical current, egg cell and nucleus from cultures somatic cell are fused together
4) new cell developed in vitro on similar way to zygote and started to form embryo
5) embryo place d in womb of surrogate mother sheep
6) embroil developed normaly
7) dolly was born

Question 38

What is therapeutic cloning?

Answer 38

Aim is to develop cells which haven’t gone through process of differentiation, cells are referred to as embryonic stem cells

Question 39

What can therapeutic stem cells do?

Answer 39

• make transplantable plants

- replace damaged tissues

Question 40

What are arguments for therapeutic cloning in humans?

Answer 40

• can grow skin to repair serious burns
• grows new heart muscle to repair ailing heart
• grow new kidney tissue to repair failing kidney
• can be used to cure serious diseases with cell therapy

Question 41

What are the arguments against therapeutic cloning in humans?

Answer 41

• involves creation and destruction of human embryos
• capable of continued divions– causing cancerous cells and cause tumours
• more embryos produced than needed, excess are killed