This document discusses the learning objectives for a lesson on molecular genetics. It covers DNA structure and function, genes, genetic transfer between organisms, and the effects of genetic engineering on society. Specifically, it aims to explain how the human insulin gene can be inserted into bacterial DNA to produce human insulin through fermentation. It also aims to discuss the social and ethical implications of genetic engineering using a real-world example.
This power point presentation explains double helical structure of DNA as proposed by Watson and Crick (1953).Attempts have also been made to high light the valuable contributions made by Rosalind Franklin and Wilkins. Brief details of different types of DNA have also been included.
A detail ppt about Genome organization with focus on all levels of organization. Most recent research and findings about CT is also added in this ppt. Detail account of 30nm fiber and its ultra structure and types is also included.
DNA is a very important fact of life. And the evolution of the DNA is an very important thing to studied in various where the biology links. In this presentation, the history of the DNA is presented in a short manner.
Ping on the E-Mail in case of the removal and false information found.
This presentation is carrying all summary about the history of genetics that who discover genes which scientist work on it and there work summary of all these things is given here and it is very helpful for the students of genetics whether they are students of plant genetics or animals.
DNA = deoxyribonucleic acid.
DNA carries the genetic information in the cell – i.e. it carries the instructions for making all the structures and materials the body needs to function.
DNA is capable of self-replication.
Most of the cell’s DNA is carried in the nucleus – a small amount is contained in the mitochondria.
This power point presentation explains double helical structure of DNA as proposed by Watson and Crick (1953).Attempts have also been made to high light the valuable contributions made by Rosalind Franklin and Wilkins. Brief details of different types of DNA have also been included.
A detail ppt about Genome organization with focus on all levels of organization. Most recent research and findings about CT is also added in this ppt. Detail account of 30nm fiber and its ultra structure and types is also included.
DNA is a very important fact of life. And the evolution of the DNA is an very important thing to studied in various where the biology links. In this presentation, the history of the DNA is presented in a short manner.
Ping on the E-Mail in case of the removal and false information found.
This presentation is carrying all summary about the history of genetics that who discover genes which scientist work on it and there work summary of all these things is given here and it is very helpful for the students of genetics whether they are students of plant genetics or animals.
DNA = deoxyribonucleic acid.
DNA carries the genetic information in the cell – i.e. it carries the instructions for making all the structures and materials the body needs to function.
DNA is capable of self-replication.
Most of the cell’s DNA is carried in the nucleus – a small amount is contained in the mitochondria.
This is my research plan presentation for postgraduate studies in Miyazaki University. Recently, I am carrying out this research for the development of citrus industry.
Chemotherapy classes
for more lectures please contact
Dr. Salah Mabrouk Khallaf
MD Medical Oncology & BMT
South Egypt Cancer Institute
Email: salahmab76@yahoo.com
DNA is really long, and the nucleus of a cell is really tiny. You might think that the DNA would get tangled, and you'd be right. Here are some methods the cell uses to keep things from getting out of control.
22.1 Types of Nucleic Acids
22.2 Nucleotide Building Blocks
22.3. Nucleotide Formation
22.4 Primary Nucleic Acid Structure
22.5 The DNA Double Helix
22.6 Replication of DNA Molecules
22.7 Overview of Protein Synthesis
22.8 Ribonucleic Acids
22.9 Transcription: RNA Synthesis
22.10 The Genetic Code
22.11 Anticodons and tRNA Molecules
22.12 Translation: Protein Synthesis
22.13 Mutations
22.14 Nucleic Acids and Viruses
22.15 Recombinant DNA and Genetic Engineering
22.16 The Polymerase Chain Reaction
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Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
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2. 2
Learning Objectives:
(a) outline the relationship between DNA, genes and
chromosomes.
(b) state the structure of DNA in terms of the bases, sugar and
phosphate groups found in each of their nucleotides.
(c) state the rule of complementary base pairing.
(d) state that DNA is used to carry the genetic code, which is
used to synthesise specific polypeptides.
(e) state that each gene is a sequence of nucleotides, as part of
a DNA molecule.
(f) explain that genes may be transferred between cells
3. 3
Learning Objectives:
(g) briefly explain how a gene that controls the production of
human insulin can be inserted into bacterial DNA to
produce human insulin in medical biotechnology.
(h) outline the process of large-scale production of insulin
using fermenters.
(i) discuss the social and ethical implications of genetic
engineering, with reference to a named example.
4. 4
"Cloning is all very well in theory, but do you have any
proof it can actually work?"
5. 5
1. We inherit traits from aunts, uncles, cousins and siblings
because family members point out the resemblance
between students and their relatives.
2. Some people think that most common traits are “better”.
3. Dominant alleles or traits are always the most common.
4. DNA is a living thing.
5. Only animal contains DNA.
6. Genes from one type organism will not function in a
different type organism.
6. 6
1. Traits can only be inherited from parents, and by
extension, grandparents.
2. No. The traits simply show up more frequently in the
human population.
3. Not necessary.
( A dominant trait may be quite rare, while a recessive trait
may be the most common one observed.)
7. 7
× DNA is a living thing.
× Genes from one type organism will not function in a different type organism.
× Only animal cells contain DNA.
4. DNA is a molecule with instructions for a cell.
5. Plants also contain DNA
6. There is a genetic code common to all living things.
8. 20.1 DNA
20.2 Genes
20.3 Transferring Genes between Organisms
20.4 Effects of Genetic Engineering on Society
Chapter
20
Molecular Genetics
9. Learning Outcomes
After this section, you should be able to:
• describe the basic unit of DNA – the nucleotide;
• state and apply the rule of complementary base
pairing.
20.1 DNA
10. 10
Chromosomes
• Inheritable materials in nucleus of a cell. Numerous genes
are located on it.
• Chromosomes can exist in coiled compact form or uncoiled
extended form.
• Cells undergoing cell division will contain chromosomes in
coiled compact form.
12. Function of DNA
• It codes for the synthesis of polypeptides.
• Many polypeptides will join together to form
protein, which is responsible for your traits.
12
13. 13
Structure of DNA
• A molecule that carries genetic information
• The basic unit of DNA is known as nucleotide;
16. “Rule of base pairing”
• Adenine (A) bonds with thymine (T)
• Guanine (G) bonds with cytosine (C)
These pairs of bases are called complementary bases.
17. • The DNA molecule is made of two
anti-parallel polynucleotide
strands. (The two strands run in
opposite directions.)
• The bases on one strand form
bonds with the bases on the other
strand according to the rule of
base pairing.
20. The two anti-parallel strands of the DNA molecule
coil to form a double helix three-dimensional
structure.
bases
sugar-phosphate
backbone
coiling of
DNA
the double helix
3D structure of
DNA
21. Coiling of DNA
Uncoiled DNA
resemble a ladder
(2D structure)
Coiled DNA
resemble a spiral
staircase/
double-helix
(3D structure)
23. 23
Activity: Build Your DNA Model
• Create a DNA model using
materials of their own choice.
• Suggested materials include
straws, pipe cleaners, pasta
• They should include a key that
explains what each item
represents. After you have
completed their models, display
the models to the whole class.
25. Checkpoint 1
1. a) State the bases that are complementary to the bases on
strand shown below:
b) State the ratio of:
(1) adenine : thymine, and
(2) guanine : cytosine
in the DNA of a cell.
Answer:
Answer:
(1)1 : 1
(2)1 : 1
26. • What is the base sequence of the DNA strand that would
be complementary to the following single-stranded DNA
molecule?
GGATCTGATCCAGTCA
A : GGAUCUGAUCCAGUCA
B : CCTAGACTAGGTCAGT
Checkpoint 2
27. • The percent of cytosine in a double-stranded DNA is
21. What is the percent of thymine in that DNA?
A 21%
B 29%
Checkpoint 3
28. • According to base pair rule, the percentage of As, Ts,
Cs, and Gs should add up to 100%, because
A
C
T
G
=
=
Adding all the
bases together
should make
up 100% of the
DNA molecule.
29. • The percent of adenine in a double-stranded DNA is 38.
What is the percent of cytosine in that DNA?
A 12%
B 38%
Checkpoint 4
30. • The percent of guanine in a double-stranded DNA is 14.
What is the percent of adenine in that DNA?
A 14%
B 36%
Checkpoint 5
34. Add 10cm3
detergent
To break nuclear
membrane
Add 10cm3
of ethanol
To separate out the
DNA strand
Add phenol red indicator
Indicate presence of DNA
35. 20.1 DNA
20.2 Genes
20.3 Transferring Genes between Organisms
20.4 Effects of Genetic Engineering on Society
Chapter
20
36. Learning Outcomes
After this section, you should be able to:
• state that DNA molecules contain the genetic
code;
• state what is meant by the genetic code;
• state that a gene is a specific sequence of
nucleotides in a DNA molecule that controls the
production of a polypeptide.
20.2 Genes
37. What is a gene?
• It is a segment of DNA.
• The nucleotide sequence
in the gene determines
the polypeptide formed.
gene
DNA
polypeptide
coded by the
gene
20.2
38. • Three bases, or codon, code for one amino acid.
• A chain of amino acids makes up one polypeptide,
which later can be used to make proteins.
Codon
on DNA
Example of amino acid coded
for
TAC Methionine (M)
TAT Alanine (A)
CAT Lysine (K)
GAG Glutamic acid (E)
ACA Serine (S)
39. “One gene, one polypeptide” theory
• The theory that each gene is responsible for the
synthesis of a single polypeptide
40. What happens when
the nucleotide
sequence in a gene
is altered?
What happens when
the nucleotide
sequence in a gene
is altered?
41. A change in the nucleotide
sequence of a gene is termed as
gene mutation.
A mutation may or may not lead to
a change in the protein product.
A change in the protein product
may or may not lead to an
observable phenotype.
Recall
Two examples of gene
mutation was mentioned
in Chapter 19. Can you
state the two examples?
(1)Albinism
(2)Sickle-cell anaemia
42. Important!
•A cell cannot directly use
the DNA template to make
proteins. It has to go through
the following stages.
How are proteins
made?
How are proteins
made?
43. (a) Transcription:
• Messages in
DNA template is copied into
messenger RNA in the
nucleus.
• (b) Translation :
messenger RNA carries
the message to cytoplasm
and ribosome helps to
convert them into proteins.
44
(a)
Transcription
(b) Translation
44. MicroQuestions
1. Describe the relationship between DNA, genes
and chromosome. [3]
2. Using the idea of molecular structure, describe
the structure of DNA and its function in leading
to a trait. [4]
45
45. 1) (a)
•Gene is a segment of the DNA molecule .
•Chromosomes are made of coiled DNA
molecules.
•DNA carries many genes along its length.
46. 1) (b)
Function:
DNA codes for the synthesis of polypeptide.
Polypeptides are used to make proteins , which are
responsible for many traits.
Structure of DNA:
• Basic unit made of nucleotide
• Nucleotide is made a phosphate group, a sugar and a
base.
• The 2 strands of polynucleotide joined together by the
‘complementary base pairing rule’ (A & T , G & C)
• 2 strands are twisted to form a double helix 3D structure
49. It is a temporary molecule that
is made when needed.
It is a permanent molecule in the
nucleus.
It is a small soluble molecule.It is a large insoluble molecule.
No fixed ratio between A and U
and between G and C.
Ratio of A:T and G:C is 1:1.
Nitrogen-containing bases are
adenine (A), uracil (U), guanine
(G) and cytosine (C).
Nitrogen-containing bases are
adenine (A), thymine (T),
guanine (G) and cytosine (C).
Sugar unit is ribose.Sugar unit is deoxyribose.
RNADNA (double helix)
DNA vs. RNA
Pure Biology
51. The biological molecules involved are:
(1) Amino acids
- There are a total of 20 different
amino acids.
(2) Transfer RNA (tRNA) molecules
- Each tRNA molecule has an amino
acid attached.
- The amino acid attached depends
on the tRNA’s anticodon.
(3) Ribosomes
- Ribosomes help make polypeptides
from mRNA molecules.
(4) mRNA molecules
Translation
anticodon
Pure Biology
53. 3
polypeptide formed
stop
codon
Amino acids are
continually attached until
the ribosome reaches the
stop codon on the mRNA.
Upon encountering the
stop codon, the ribosome
leaves the mRNA.
The complete polypeptide
is produced.
URL
Pure Biology
54. 20.1 DNA
20.2 Genes
20.3 Transferring Genes between Organisms
20.4 Effects of Genetic Engineering on Society
Chapter
20
Pure Biology
55. Learning Outcomes
After this section, you should be able to:
• define genetic engineering;
• describe human insulin production as an example
of an application of genetic engineering;
• differentiate between selective breeding and
genetic engineering.
20.3
Pure Biology
56. 57
“Pigs that glow in the dark””
• The scientists will use
the transgenic pigs to
study human disease.
• Because the pig's
genetic material
encodes a protein that
shows up as green, it
is easy to spot.
http://science.howstuffworks.com/framed.htm?parent=question388.htm&url=http://news.bb
57. • Genetic engineering refers to the manipulation of an
organism’s genetic material.
• It involves the transfer of genes from one organism to
another.
• This is done by the use of a vector.
• A vector molecule is DNA molecule that is used to
carry the gene or genes to be transferred.
• Plasmids (circular DNA) from bacteria are commonly
used as vectors.
Genetic engineering
58. The process
Isolate the desired gene
- Cut the gene using restriction enzymes.
Insert the gene into the vector DNA
- Restriction enzymes that were used to cut the
desired gene are used to cut the vector DNA.
- Both the cut vector DNA and gene are mixed
together with DNA ligase, an enzyme that will help
join the two molecules together.
Insert the recombinant plasmids into bacteria
- Mix recombinant plasmids with bacteria and heat- or electric-shock
the cells.
1
2
3
20.3
59. • Mass production of human insulin for type 1 diabetes
patients was made possible through the use of genetic
engineering.
• The human insulin gene is transferred to bacterial cells
that are able to express the gene. The product (insulin)
can then be harvested.
Producing human insulin
Background:
Type 1 diabetes is caused by the inability of the islets
of Langerhans to produce sufficient insulin.
60. insulin gene
cut using restriction
enzyme
sticky end
DNA fragment that contains
the insulin gene
Isolating the human insulin gene
1
61. Inserting the gene into the vector2
cut by same
restriction enzyme
sticky ends
insulin gene inserted
into plasmid
insulin gene
bacterial plasmid
62. Inserting the recombinant
plasmids into bacteria
3
recombinant plasmid
(bacterial plasmid with
human insulin gene
inserted)
bacterial DNA
recombinant
plasmid
transgenic bacterium
63. • The transgenic bacteria need to be burst open in
order to extract the human insulin that is produced in
the bacteria.
• In order to obtain large amounts of human insulin,
large amounts of transgenic bacteria need to be
cultured.
• This is done through the use of large sterile
containers called fermenters.
Large-scale production of human insulin
65. • Creation of transgenic plants that are resistant to
herbicides.
• Creation of transgenic plants that are pest-resistant.
• Gene therapy – healthy genes can be transferred from
one person to the cells of another person with
defective genes.
Other applications of genetic engineering
20.3
66. • Genes can be transferred between organisms of
different species (as shown in the production of
insulin) and between organisms of the same species.
• An example of gene transfer between organisms of
the same species is the transfer of a pest-resistant
gene from wild wheat plants to common wheat plants
that are grown as crop.
Note that:
20.3
67. Selective breeding vs. genetic engineering
More efficient as transgenic
organisms grow faster and may
require less food
Less efficient as organisms grow
more slowly and may require more
food
A process which uses individual
cells that reproduce rapidly in a
small container in a laboratory.
Slow process that involves several
generations.
Selection of genes before transfer
eliminates the risk of transferring a
defective gene.
There is a possibility that defective
genes will be transmitted to the
offspring.
Genes from an organism can be
inserted into non-related species or
different species.
Organisms involved in selective
breeding must be closely related or
of the same species.
Genetic engineeringSelective breeding
68. 20.1 DNA
20.2 Genes
20.3 Transferring Genes between Organisms
20.4 Effects of Genetic Engineering on
Society
Chapter
20
Molecular Genetics
69. Learning Outcomes
After this section, you should be able to:
• discuss the advantages and disadvantages of
genetic engineering;
• state the social and ethical implications of this
technology.
70. Advantages of genetic engineering
Nutritional quality of foods are
improved.
Development of foods
designed to meet specific
nutritional goals
The use of costly pesticides that may
damage the environment is reduced.
Development of pesticide-
resistant crops
Farmers are able to grow crops in
environmental conditions that are not
favorable for cultivating most crops.
Production of crops that
grow in extreme conditions
Drugs like human insulin become
more affordable.
Low cost production of
medicines
Benefits to societyApplications of genetic
engineering
71. Disadvantages of genetic engineering
Environmental hazards
• Genetically-modified (GM) crop plants that produce insect
toxins may result in the deaths of insects that feed on
them and may result in loss of biodiversity.
Economic hazards
• If the prices of the seeds of modified crop plants are not
regulated, poorer farmers may not have the financial
capacity to benefit from this technology while richer
farmers continue to get richer through the technology.
72. Disadvantages of genetic engineering
Social and ethical hazards
• Genetic engineering may lead to class distinctions.
• Some religions do not approve of genetic engineering as
it may not be appropriate to alter the natural genetic
make-up of organisms.
Health hazards
• Genes that code for antibiotic resistance may be
accidentally incorporated into bacteria that cause human
diseases.
Editor's Notes
Note:
The sugar-phosphate backbone is always the same whereas the bases are variable.
Note:
Purines (adenine, guanine) always pair with pyrimidines (thymine, cytosine). Specific pairing between adenine and thymine, and guanine and cytosine occurs as optimum hydrogen bonding that can be established in those combinations.
It is this specificity in base pairing that led to Edwin Chargaff’s finding that, in the DNA of a cell, the amount of adenine = the amount of thymine, and the amount of guanine = the amount of cytosine. (However, after learning of this, Chargaff did not come to the conclusion that specific base pairing occurs. This rule of base pairing was instead first proposed by Watson and Crick, the famous scientists that discovered the double helix structure of DNA.)
Slide 11 (hidden) can be used to give students a visual representation of the hydrogen bonding between complementary bases.
Slide 12 (hidden) contains directives for a mini project that requires students to find out more about Chargaff and his contributions to science. This topic can be used to bridge over to the discovery of the double helix structure of DNA by Watson and Crick.
*To un-hide slides, go to ‘Normal View’ or ‘Slide Sorter’ and right click on the slide. Unselect ‘Hide Slide’.
Note:
The diagram on the right, may be used to point out to students how the two strands in a DNA molecule are anti-parallel.
Note:
If students have difficulty visualising the structure of the double helix, it may be helpful to state that the structure resembles a spiral staircase.
Note:
The answer to the first question comes out step-wise.
Use this flowchart to explain the extraction of DNA in details.
Describe the fact that the cell and nuclear membrane needs to be broken down before the DNA can be extracted.
Note:
A DNA molecule can contain more than one gene along its length.
A gene consists of two polynucleotide strands. One of the strands is termed the coding strand, while the other the non-coding strand. This will be further elaborated in slides describing protein synthesis.
Other names for the coding strand: sense strand, non-template strand.
Other names for the non-coding strand: antisense strand, template strand.
Note:
The codon is also known as the triplet code. The genetic code can be in the form of DNA or RNA sequences. It is important that the students understand this and state, when answering questions, whether the codon/triplet code being mentioned is a DNA sequence or RNA sequence.
Note:
Slide 19 (hidden) can be used for revision of the two examples of gene mutation that were covered in the chapter on heredity.
*To un-hide slides, go to ‘Normal View’ or ‘Slide Sorter’ and right click on the slide. Unselect ‘Hide Slide’.
Note:
The DNA strands unzip at the segment where the gene is located.
Transcription occurs: The sequence of bases on one of the DNA strands (the template strand) is used to make the mRNA, following the rule of base pairing. Note that mRNA does not contain the thymine (T) base. Instead, adenine (A) in DNA pairs with uracil (U) in mRNA. The template strand refers to the non-coding strand. It is the DNA strand from which mRNA is made. The coding strand of the DNA is the strand that has the same base sequence as the mRNA molecule.
The completed mRNA molecule leaves the nucleus through the nuclear pore and attaches to a ribosome in the cytoplasm. This is the start of translation.
Note:
Amino acids and transfer RNA (tRNA) molecules are found in the cytoplasm.
Anticodons are sequences that can bind to complementary codons on mRNA.
Note:
Translation starts with an mRNA molecule attaching to a ribosome. Two tRNA molecules with the correct anticodons then attach to the mRNA codons. A peptide bond is formed between the two amino acids on the tRNA molecules.
Once the peptide bond is formed, the ribosome moves one codon to the right of the mRNA. As the ribosome moves, the first tRNA is released and the third tRNA attaches to the ribosome.
(continued on next slide)
Note:
A stop codon on an mRNA molecule can be UGA, UAA or UAG. A stop codon has no corresponding tRNA molecule.
Click on the Video-URL button to be directed to a website where an animation on mRNA translation can be found. (On the webpage, scroll down to Chapter 12, select Tutorial 12.3 select ‘Animation’) The animation lasts for about two minutes.
Note that this animation clip contains more details than what is discussed in the textbook.
Namely,
There is mention of a start codon – which codes for Methionine.
Reference is made to the E, P and A sites of the ribosome.
tRNA that has an amino acid attached is referred to as amino-acyl tRNA.
The chemistry behind peptide bond formation is briefly mentioned.
Note:
The first step (Isolate the desired gene) can also be done using polymerase chain reaction (PCR) technology.
The vector DNA mentioned in the second step is typically a bacterial plasmid. If PCR is used in the first step, the enzymes used to cut the vector DNA are selected based on the PCR primer design.
Recombinant plasmids are plasmids that are made of DNA molecules that do not naturally exist together. In this case, the recombinant plasmid is made of DNA from two different organisms. When we heat shock or electric shock bacterial cells, we cause their cell surface pores to open. This increases the chance of the recombinant plasmid entering the cells. Other than insertion into bacterial cells, the recombinant plasmid can also be inserted into animal or plant cells using other methods (e.g. microinjection).
This process will be pictorially shown in Slides 32 and 34 as an example of genetic engineering (producing human insulin in bacterial cells).
Tell students that an organism that acquires a foreign gene is called a transgenic organism. As such, the bacterial cell in which the human insulin gene is transferred into is termed transgenic bacterium.
Note:
The following slides show pictorially the process of genetically engineering a bacterium so that it expresses the gene for human insulin.
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The human chromosome containing the human insulin gene is identified and isolated.
The portion of DNA that contains the gene is cut using a restriction enzyme.
Usually an enzyme that produces sticky ends (as opposed to blunt ends) is used. (Sticky ends have ‘overhangs’ – The DNA molecules have ends that have nucleotides that are unpaired. Blunt ends do not have ‘overhangs’ – The DNA molecule ends with a base pair.)
Slide 33 (hidden) shows an example of a sticky end and an example of a blunt end. Students can be asked for their opinions as to why sticky ends are preferred.
*To un-hide slides, go to ‘Normal View’ or ‘Slide Sorter’ and right click on the slide. Unselect ‘Hide Slide’.
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EcoRI is an example of an enzyme that will produce sticky ends. As shown, the cut results in the DNA having some nucleotides that are unpaired. These unpaired nucleotides are called the DNA overhangs.
SmaI is an example of an enzyme that will produce blunt ends. As shown, the cut results in the DNA ending with a base pair.
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The bacterial plasmid (vector) is cut with the same enzyme that was used to cut the gene.
The gene fragment and the cut vector is mixed in a solution that contains DNA ligase. DNA ligase helps to join the two DNA fragments together.
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The recombinant plasmids are mixed with bacteria (usually E.coli). The bacteria are heat-shocked or given an electric shock. This opens up the pores on the bacteria cell surface such that the recombinant plasmids can enter.
The bacteria with the recombinant plasmid will express the gene and produce human insulin. To extract and purify the human insulin in the bacteria for medical purposes, the bacteria will have to be burst open.
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Although the container used to culture large quantities of transgenic bacteria are called fermenters, the insulin production by transgenic bacteria is not a fermentation process.
Discuss the various components of a large-scale fermenter. Elaborate more on the various components and their function. Details can be found in the textbook.
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Examples:
The gene that codes for the enzyme cyanamide hydratase (found in Myrothecium verrucaria, a soil fungus) is transferred to crop plants so that they are resistant to herbicides.
Wild species of wheat contain a gene that confers resistance to the Hessian fly (a major wheat pest). This gene can be transferred to the common wheat plant, that is used as a crop plant, so that it is resistant to this pest.
Gene therapy is used to treat patients with cystic fibrosis. Healthy genes are inserted into the lung cells of the patients.
(The last two examples are examples of gene transfer between organisms of the same species.)
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(continued on next slide)
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More examples of each hazard are listed in the textbook.
The next slide (hidden) contains directives for a class activity. Students are asked to listen to a discussion on the ethical implications of genetic engineering. After listening to the talk, the students are to form groups to prepare a presentation on their own views on genetic engineering.
The full video is about an hour long. The video can be stopped at time 23:45 (After Topic 6: Improvement vs. Cure). Students should be sufficiently exposed to the nature of the debate on genetic engineering in these 23 plus minutes.
*To un-hide slides, go to ‘Normal View’ or ‘Slide Sorter’ and right click on the slide. Unselect ‘Hide Slide’.
Note:
The full video is about an hour long. The video can be stopped at time 23:45 (After Topic 6: Improvement vs. Cure). Students should be sufficiently exposed to the nature of the debate on genetic engineering in these 23 plus minutes.