Genetic Engineering bullet points


11 Δεκ 2012 (πριν από 8 χρόνια και 7 μήνες)

576 εμφανίσεις

Genetic Engineering


3. Selective Breeding Allowing only those animals with desired characteristics to produce
the next generation

4. Humans use selective breeding, which takes advantage of naturally occurring genetic
variation in plants, anim
als, and other organisms, to pass desired traits on to the next
generation of organisms Nearly all domestic animals and plants have been produced by
selective breeding

5. Hybridization Crossing dissimilar individuals to bring together the best of both
anisms Hybrids are often hardier than their parents

16. Inbreeding The continued breeding of individuals with similar characteristics

17. The goal is to maintain the desired characteristics of a line of organisms There are
always risks to inbreeding Beca
use most members of a species are genetically similar,
there is a chance that a cross between two individuals will bring together two recessive
alleles for a genetic defect

18. Increasing Variations Breeders can increase the genetic variation in a populat
ion by
inducing mutations You can increase the mutation rate by using the following…
Radiation Chemicals Most mutations can be harmful but sometimes they can bring
desirable characteristics

19. Producing New Kinds of Bacteria Using this method of inducing

mutations, scientists
have made many useful strains of bacteria Ex.) bacteria that can digest oil

20. Producing New Kinds of Plants Scientists use drugs that prevent chromosomal
separation during meiosis This results in cells that have double or triple t
he normal
number of chromosomes called… Polyploidy

Manipulating DNA

22. Until recently, animal and plant breeders could not modify the genetic code of living
things They were limited by the variation that exists in nature Today scientists can go
right t
o the genetic code and re
write an organisms DNA, transfer genes at will from one
organism to another and design new living things to meet specific needs

23. Different techniques are used to… Extract DNA from cells Cut DNA into smaller
pieces Identify the

sequence of bases in a DNA molecule Make unlimited copies of DNA

24. Genetic Engineering Making changes in the DNA code of a living organism

25. DNA Extraction DNA can be extracted from most cells by a simple chemical
procedure The cells are opened and
the DNA is separated from other parts of the cell

26. Cutting DNA DNA molecules are much too large to be analyzed so biologists cut
them into smaller fragments

27. Restriction Enzymes Cuts DNA at a specific sequence of nucleotides

28. Separating DNA Ele
ctrophoresis Mixture of DNA fragments is placed at one end of a
porous gel Electric charge is applied Negatively charged DNA molecules move towards
positive ends Small fragments move faster and farther than larger ones

30. Using the DNA Sequence Knowing
the sequence of an organisms DNA allows
researchers to study specific genes, to compare them with the genes of other organisms,
to try to discover the functions of different genes and gene combinations

31. Cutting and Pasting Short sequences can be assemb
led using laboratory machines
known as DNA synthesizers “ Synthetic” sequences can be joined to “natural” ones using
enzymes that splice DNA together The same enzymes make it possible to take a gene
from one organism and attach it to the DNA of another org

32. Recombinant DNA DNA molecules produced by combining DNA from other sources

34. Making Copies In order to study genes, biologists often need to make copies of a
particular gene

35. Polymerase Chain Reaction (PCR) Technique used to copy DNA Inve
nted by
American scientists Kary Mullis Autobiography

Dancing Naked in the Mind Field

37. How PCR Works Add a primer to the portions of a sequence you want to copy Heat
DNA to separate its two strands, then cool to let the primers bind to single
DNA polymerase starts making copies of the region between the primers

Cell Transformation

44. It would do little good to modify a DNA molecule in a test tube if it were not possible
to put that DNA back into a living cell and make it work During t
ransformation, a cell
takes in DNA from outside the cell. This external DNA becomes part of the cells DNA

45. Transforming Bacteria 1. The foreign DNA is first joined to a small circular DNA
molecule known as a plasmid Plasmid

small circular DNA molecul
e Easily replicated

46. Transforming Bacteria 2. The plasmid has a genetic marker

a gene that makes it
possible to distinguish bacteria that carry the plasmid (and foreign DNA) from those that


48. Transforming Plant Cells Many plant cells c
an be transformed by using a bacteria that
usually produces tumors in a plants cells Researchers have inactivated the tumor
producing gene and inserted a piece of foreign DNA into the plasmid The recombinant
plasmid can then be used to infect plant cells I
f transformation is successful, the
recombinant DNA is integrated into one of the chromosomes of the cell


50. Transforming Animal Cells Animal cells can be transformed in the same ways as
plant cells Many egg cells are large enough that DNA can be d
irectly injected into the
nucleus Once inside enzymes normally responsible for DNA repair and recombination
may help insert the foreign DNA into the chromosomes of the injected cell

51. Knocking Out Genes Recently, it has become possible to eliminate part
icular genes
by careful design of the DNA molecules that are used for transformation DNA molecules
can be constructed with two ends that will sometimes recombine with specific sequences
in the host chromosome Once they do, the host gene may be lost or spec
ifically replaced
with a new gene This makes it possible to pinpoint the specific functions of genes

Applications of Genetic Engineering

57. Transgenic organisms Organisms that contain genetic information from other species
Q: How does one do this? A: Ta
ke a gene from one organism and place it in another

58. This idea has sparked the new booming industry of biotechnology

59. Fun With Fireflies There is an enzyme that makes fireflies glow Luciferase Could we
take a gene out of an animal and put it in som
ething else? Could we get things that don’t
glow, to glow

60. Glowing Tobacco Plant Put luciferase gene in a tobacco plant and you can get a
glowing tobacco plant

69. Transgenic Microorganisms Before: Diabetics had to use insulin from cadavers Now:
We ma
ke bacteria that produce human proteins such as insulin, growth hormone, clotting
factor Future: Bacteria may produce substances to fight cancer, make raw materials for
plastic and fibers

70. Transgenic Animals There are currently no transgenic animals th
at are approved for
human consumption. But there are a lot of experimental studies being done

71. Transgenic Animals Mice susceptible to cancer Mice made to have human immune
systems Livestock with growth hormone Chickens resistant to bacterial infections

cause us food poisoning Mad cow resistant cows Sheep and pigs that produce our
proteins Spider web goats

72. Spider Web Goats? Take the gene for making spider web silk

73. Put it in a goat Then milk it Extract the spider web silk in large quantitie
s… And we
could have…

74. The best bullet proof vest ever! Strongest steel cables And much more…

75. Transgenic Plants Already here, already controversial Here are some facts and myths
There are only six categories of trangenic plants

76. Soy Beans 50 p
ercent of soy beans today are genetically modified

77. Corn 25 percent of corn is genetically modified

78. Insect Resistant The bulk of both soy beans and corn that is genetically modified is
modified to have a natural insecticide

79. Herbicide resistan
t Others resist weed killing chemicals

80. The other categories Virus resistant Delayed fruit ripening Altered oil control Pollen

81. Golden Rice Rice genetically modified to have added vitamins Not marketed to the
public yet

82. Transgenic Plan
t Myths The fish tomato and the fish berry Genetically modify plants
to have a fish gene that makes them able to live in colder temperatures Experimentally
tested, but never worked

83. Still controversial Soybeans with brazil nut allergens Terminator seed

84. A Rising Trend As more and more farmers are realizing the efficiency of these GM
plants, the more they will be used

85. Clone A member of a population of genetically identical cells produced by a single

86. How to get a clone in 4 easy steps
1. Remove the nucleus of an egg

87. How to get a clone in 4 easy steps 2. Fuse egg with a cell taken from another
organism 3. Place in the uterus of a foster mother 4. Foster mother gives birth to cloned

88. Donor Nucleus These two cells are fused u
sing an electric shock. Fused Cell The
fused cell begins dividing normally. Embryo The embryo is placed in the uterus of a
foster mother. The embryo develops normally into a lamb

Dolly Egg Cell An egg cell is
taken from an adult female sheep. The nucleus o
f the egg cell is removed.

89. Dolly First time this was done in a mammal was in 1997 A gigantic scientific
breakthrough at the time

90. We have also cloned Cows Pigs Mice Cats Dogs Horse Monkey

91. Starlight…guess where it was cloned

92. The cutest cl
one First cloned cat “ CC ”

93. Cloned Mice Nucleus Donor Egg Donor Surrogate Mother Cloned babies

94. Female gives birth to her own dam twin! Dam = female horse

95. The worlds first cloned dog

96. The latest clones Will be used to study stem cells And

animal to human transplants

97. Breaking News in the Cloning World! Scientists just announced today that for the
first time, they have successfully cloned a rhesus monkey embryo

98. Pros and Cons of Cloning Pros Saving endangered species Transgenic anim
als for
human consumption Organ and tissue transplants Cons Cloned animals have genetic
defects Health problems

99. Should we reproductively clone humans? No! It took 188 tries on Dolly Success rate
of .4 on the horse Success rate of 1.6 on the dog How ma
ny humans would die before this