Here is a possible design for an experiment to assess one factor affecting the rooting of stem cuttings: - Plant species chosen: Coleus canina (common name cut-leaf coleus), which is known to form roots readily from stem cuttings. - Factor to be tested: Effect of auxin treatment on root formation. - Materials: Coleus canina stem cuttings, water, rooting hormone powder containing auxin (IBA). - Methods: Take stem cuttings of uniform size and remove lower leaves. Dip half the cuttings in auxin powder solution and half in water only. Insert all cuttings in potting soil. Maintain soil moisture and observe over 4 weeks.

1. 3.5 Genetic modification and biotechnology
Essential idea: Biologists have developed techniques for
artificial manipulation of DNA, cells and organisms.
http://www.nacentralohio.com/wp-content/uploads/2013/01/WW_0113_GMO_AppleOrange.jpg

2. Understandings
Statement Guidance
3.5 U.1 Gel electrophoresis is used to separate proteins or
fragments of DNA according to size
3.5 U.2 PCR can be used to amplify small amounts of DNA.
3.5 U.3 DNA profiling involves comparison of DNA.
3.5 U.4 Genetic modification is carried out by gene transfer
between species.
3.5 U.5 Clones are groups of genetically identical organisms,
derived from a single original parent cell.
3.5 U.6 Many plant species and some animal species have natural
methods of cloning.
3.5 U.7 Animals can be cloned at the embryo stage by breaking up
the embryo into more than one group of cells.
3.5 U.8 Methods have been developed for cloning adult animals
using differentiated cells.

3. Applications and Skills
Statement Guidance
3.5 A1 Use of DNA profiling in paternity and forensic investigations.
3.5 A2 Gene transfer to bacteria using plasmids makes use of restriction
endonucleases and DNA ligase.
3.5 A3 Assessment of the potential risks and benefits associated with genetic
modification of crops.
3.5 A4 Production of cloned embryos produced by somatic-cell nuclear
transfer. [Dolly can be used as an example of somatic-cell transfer.]
3.5 S1 Design of an experiment to assess one factor affecting the rooting of
stem-cuttings. [A plant species should be chosen for rooting
experiments that forms roots readily in water or a solid medium.]
3.5 S2 Analysis of examples of DNA profiles. [Students should be able to
deduce whether or not a man could be the father of a child from the
pattern of bands on a DNA profile.]
3.5 S3 Analysis of data on risks to monarch butterflies of Bt crops.

4. 3.5 U1 Gel electrophoresis is used to separate proteins or fragments of
DNA according to size
Visualizing DNA
Sequences
• Enzymes are used to cut DNA into
fragments of various lengths.
• These fragments are placed into small
wells at one end of the gel in a gel box
filled with a buffer (which conducts a
current).
• The electrical current running through the
box has a positive on one side and negative
side (DNA is negative and attracted to the
positive).
• The fragments of DNA will move through
the gel based on size and charge.
• The smallest particles that are charged go
the farthest in the gel, while the large non-
charged particles fall out and embed in the
gel the quickest.

5. 3.5 U1 Gel electrophoresis is used to separate proteins or fragments of
DNA according to size

6. 3.5 U1 Gel electrophoresis is used to separate proteins or fragments of
DNA according to size

7. • Genetic screening is the testing of
an individual for the presence or
absence of a particular gene.
There are many potential uses of
genetic screening.
• The purpose may be to identify
disease carriers. e.g. Carriers of
Cystic Fibrosis or PKU
• The purpose may be to inform the
treatment of a disease e.g. HLA-
27b associated with types of
Arthritis (not causal).
3.5 U1 Gel electrophoresis is used to separate proteins or fragments of
DNA according to size
http://www.dls.ym.edu.tw/ol_b
iology2/ultranet/Chromo7.gif

8. Advantages and of genetic
screening
• Early Diagnosis of diseases
therefore reducing the
accumulation of the damaging
effects of some diseases eg.
PKU/ Guthrie test
• Screening of parents who may
be carriers of alleles that may
cause the diseases. In this way
the frequency of the disease
can be reduced in the
population
• Reducing the frequency of the
allele through controlled IVF
for embryos not carrying the
allele
3.5 U1 Gel electrophoresis is used to separate proteins or fragments of
DNA according to size
http://media2.wcpo.com/photo/2014/08/06/wcpo-
baby_1407374007598_7250945_ver1.0_640_480.jpg

9. 3.5 U2 PCR can be used to amplify small amounts of DNA.
• PCR (polymerase chain reaction) is a
laboratory technique that takes a single
or few copies of DNA and amplifies
them to generate millions or more
copies of a particular DNA sequence.
• When you collect DNA from different
sources such as sperm samples or small
drops of blood, there are usually very
little usable cells to collect DNA.
• Therefore, PCR is used to create enough
DNA to be analyzed for investigations
such as forensics or custody cases.
• Once large quantities of the DNA have
been created, other methods such as gel
electrophoresis are used to analyze the
DNA.
Click4Biology

10. 3.5 U2 PCR can be used to amplify small amounts of DNA.
• For analysis of dead
organisms (wooly
mammoth).
• To make more copies of
DNA found at crime
scenes.
• From a single
embryonic cell for
prenatal diagnosis

11. 3.5 A.1 Use of DNA profiling in paternity and forensic investigations.
1. The first step in identifying an unknown child is to
first match the bands (size and location) from the
mother that appear in the child. A good way to do
this is to mark the child with the same color as the
mother for the bands that match or to put a small
M next to the matching bands.
2. The next step is to match the remaining bands
with one of the unknown samples from the
different father possibilities. As 50% of the DNA
inherited in the child will come from the mother
and 50% of the DNA will come from the father, the
remaining bands should match with the unknown
father’s sample.
3. Once again, colors can be used to match the child’s
remaining bands to the correct father’s bands or
by using other notation such as F3 to mark the
matching bands.
4. A similar technique can be used in criminal
investigations using the victim’s blood and the
possible suspect’s blood to match an unknown
sample found at a crime scene
http://www.atdbio.com/img/articles/STR-analysis-parentage-large.png

12. 3.5 A.1 Use of DNA profiling in paternity and forensic investigations.

13. Case 7286224:
The Green Street Holigans
3.5 A.1 Use of DNA profiling in paternity and forensic investigations.

14. DNA Profile Results:
Case 7286224
3.5 A.1 Use of DNA profiling in paternity and forensic investigations.

15. DNA Profile Results: Case 7286224
3.5 A.1 Use of DNA profiling in paternity and forensic investigations.

16. A Paternity Case: is he the father?
3.5 S.2 Analysis of examples of DNA profiles. [Students should be able to
deduce whether or not a man could be the father of a child from the
pattern of bands on a DNA profile.]

17. Sample Question:

18. Sample Exam Question: Answer

19. Genetically Modified Organism (GMO)Plant Examples:
Golden Rice enriched with beta-carotene which converts into vitamin A
3.5 U.3 Assessment of the potential risks and benefits associated with
genetic modification of crops.
http://upload.wikimedia.org/wikipedia
/commons/2/29/Golden_Rice.jpg

20. Potential benefit
1. Higher yields
2. Less land need to grow
3. Less pesticides sprayed
4. Could add genes for
certain proteins, vitamins
or possible vaccines
5. Crops last longer or don’t
spoil during storage
6. Can use pest resistant
crops or modified crops
in areas where water
availability is limited
7. Varieties of crops lacking
certain allergens or toxins
Potential harm
1. Long term effects on humans are
unknown
2. Animals may be harmed for Bt
3. Cross-pollination could occur with
wild species giving them a
competitive advantage. This could
allow these plants to outcompete
and eliminate other plants
(decrease biodiversity).
4. Some people or livestock might
have allergic reactions to certain
proteins produced by transferred
genes
3.5 U.3 Assessment of the potential risks and benefits associated with
genetic modification of crops.

21. 3.5 U.3 Assessment of the potential risks and benefits associated with
genetic modification of crops.
Benefits and risks of Genetic Transfer (GMO)
•Example Maize crop can be damaged by corn borer insects.
A gene from a bacterium has been transferred to maize. The gene codes for a
bacterial protein called Bt toxin that kills the corn borers

22. • Gene cloning: process by which
scientists can product multiple
copies of specific segments of
DNA that they can then work
with in the lab
Tools of Genetic Engineering
• Restriction enzymes used to cut
strands of DNA at specific
locations (restriction sites)
– Restriction Fragments have at
least 1 sticky end (single-
stranded end)
• DNA ligase: joins DNA fragments
• Cloning vector: carries the DNA
sequence to be cloned (eg.
bacterial plasmid)
3.5 U.4 Genetic modification is carried out by gene transfer between
species.

23. • Usually a virus (bacteriophage)
or a bacterial plasmid.
• A plasmid is a small, circular
piece of DNA.
• The virus will insert the gene on
its own.
• A plasmid will be taken up in
bacteria through
transformation.
3.5 U.4 Genetic modification is carried out by gene transfer between
species.

24. 3.5 U.4 Genetic modification is carried out by gene transfer between
species.
Vector: Bacteriophage is a virus that infects bacteria.

26. Gene Transfer (gene cloning)
3.5 A.2 Gene transfer to bacteria using plasmids makes use of
restriction endonucleases and DNA ligase.

27. 3.5 U.4 Genetic modification is carried out by gene transfer between
species.
• A gene produces a certain polypeptide in an organism.
• Since the genetic code is universal, when a gene is removed from one species and
transferred to another the sequence of amino acids in the polypeptide produced
remains unchanged.
• Gene modification has been used to introduce new characteristics to certain animal
species. For example goats that produce milk containing spider silk and bacteria
that produce human insulin. A plant example is the production of golden rice that
contains beta-carotene .

28. Gene Transfer in Insulin Production:
3.5 U.4 Genetic modification is carried out by gene transfer between
species.

29. 3.5 U.4 Genetic modification is carried out by gene transfer between
species.

30. 3.5 S.3 Analysis of data on risks to monarch butterflies of Bt crops.

31. 3.5 U.6 Many plant species and some animal species have natural
methods of cloning.
• Plants use a variety of
natural methods of cloning
involving stems, roots,
leaves or bulbs.
• Garlic bulbs are modified
plant leaves. All the bulbs
in the group are genetically
identical to each other.
• Strawberry plants grow
horizontal stems called
runners that grow roots
into the soil. These small
plants develop into
independent cloned
strawberry plants http://www.caithness.org/photos/fpb/2009/february/aspen/aspen_5.jpg
http://gardenpool.org/wpcontent/uploads/2010
/11/strawberry-plant.jpg

32. • At the very early embryo stage, cells
are still pluripotent (meaning they can
become any type of tissue)
• These cells can be separated
artificially in a laboratory in order to
create more than one of the same
organism
• The separated pluripotent cells can
then be inserted into the uterus of a
surrogate mother or mothers in order
to produce genetically identical
offspring
• The separation of cells has to happen
early in development, preferably the 8
cell stage
• This ability was first discovered by
trying on Sea anemone
3.5 U.7 Animals can be cloned at the embryo stage by breaking up the
embryo into more than one group of cells.

33. 3.5 U.8 Methods have been developed for cloning adult animals using
differentiated cells.
• Once cells start to differentiate and
embryos develop into a fetus and
eventually an adult cloning
becomes much more difficult
• Therapeutic cloning is an example
of cloning using differentiated cells
• This type of cloning can be used to
create a specific tissue or organ
• Cloning using differentiated cells
can also be used to reproduce
organisms like dolly the sheep. This
is done through somatic-cell
nuclear transfer.

35. • Organisms that reproduce asexually, produce genetically identical
offspring
• Identical twins in humans are also clones
3.5 A.4 Production of cloned embryos produced by somatic-cell nuclear
transfer. [Dolly can be used as an example of somatic-cell transfer.]

36. 3.5 A.4 Production of cloned embryos produced by somatic-cell nuclear
transfer. [Dolly can be used as an example of somatic-cell transfer.]

37. Step 1
A cell was taken
from udder of
adult sheep and
grown in culture
in a laboratory to
create many
daughter cells.
3.5 A.4 Production of cloned embryos produced by somatic-cell nuclear
transfer. [Dolly can be used as an example of somatic-cell transfer.]

38. Step 2: An egg was
taken from another
sheep, and its nucleus
was removed.
Step 3: The udder cell and the
de-nucleated egg were fused by
electricity, stimulating the egg to
develop as if it had been fertilized.

39. 3.5 A.4 Production of cloned embryos produced by somatic-cell nuclear
transfer. [Dolly can be used as an example of somatic-cell transfer.]

40. Step 4: The embryo that
developed was implanted
into a surrogate mother
sheep, and was born as
Dolly, with the exact DNA
from the original udder cell.
3.5 A.4 Production of cloned embryos produced by somatic-cell nuclear
transfer. [Dolly can be used as an example of somatic-cell transfer.]

41. 3.5 A.4 Production of cloned embryos produced by somatic-cell nuclear
transfer. [Dolly can be used as an example of somatic-cell transfer.]

42. 3.5 S.1 Design of an experiment to assess one factor affecting the
rooting of stem-cuttings. [A plant species should be chosen for rooting
experiments that forms roots readily in water or a solid medium.]