BIOTECHNOLOGY Unit 8

PART 1

BASIC/FUNDAMENTAL SCIENCE VS. APPLIED SCIENCE

! Basic/Fundamental Science – the development and establishment of information to aid our understanding of the world.

! Applied Science – a discipline of science that applies existing scientific knowledge/information to develop practical applications, such as technology and inventions.

! Fossil Fuel example.

BIOTECHNOLOGY

! Biotechnologies are created using applied science. All biotechnologies are made by manipulating (cutting with restriction enzymes, copying using PCR, transplanting using transformation and recombination) DNA.

! Biotechnologies can be used to !  Produce transgenic organisms !  Produce clones !  Study diseases and evolution !  Produce new medical treatments

PART 2

CLONING

!  Clone – a genetically identical copy of a gene or of a whole organism.

!  Examples of cloning in nature: !  Plants – vegetative propagation !  Bacteria – binary fission !  Invertebrates – regeneration

!  Mammals, like humans, cannot clone themselves in nature. However, through biotechnologies it is now possible.

!  In 1997 a sheep named Dolly became the first clone of an adult mammal.

!  The success of Dolly led to the cloning of adult cows, pigs, and mice.

MAMMALIAN CLONING PROCESS

1.  An unfertilized egg is taken from the mammal you are cloning, and the egg’s nucleus is removed.

2.  Then the nucleus of a somatic cell of the individual you are cloning is implanted into the egg.

3.  The egg is stimulated and starts dividing, at which point it is an embryo.

4.  After the embryo grows for a few days, it is transplanted into a female’s uterus.

MAMMALIAN CLONING PROCESS

PROS AND CONS OF CLONING

! Pros: !  It allows for extraordinary studies in how cloned

mammal organs may be used in humans. !  It could help save endangered species.

! Cons: !  The success rate in mammals is very low. It takes

hundreds of tries to produce one clone and sometimes the clone isn’t as healthy as the original.

!  Ecological concerns because cloned animals would reduce biodiversity in the wild.

PART 3

GENETIC ENGINEERING

!  Genetic Engineering – the changing of an organism’s DNA to give the organism new traits.

!  Genetic engineering is possible because the genetic code is universal and shared by all organisms.

!  This means, you can take a gene from a bacterium and place it into a human. Or a redwood tree to an ant. The possibilities are endless.

!  Basic genetic engineering is based on the use of recombinant DNA biotechnologies.

RECOMBINANT DNA !  Recombinant DNA –

DNA that contains genes from more than one organism.

!  Bacteria are commonly used in making recombinant DNA.

!  The main reason for this is that bacteria have tiny rings of DNA called plasmids. Plasmids are closed loops of DNA that are separate from the bacterial chromosome.

RECOMBINANT DNA

!  Recombinant DNA is found naturally in bacteria that take in DNA from different organisms and add it to their own.

!  Scientists using applied science, are now making artificial recombinant DNA.

!  Simply put, scientists take foreign DNA and insert it into a plasmid to make recombinant DNA

WHY MAKE RECOMBINANT DNA?

! After a gene is added to a plasmid, the genetically engineered plasmid can be put back into bacteria.

!  In a way, the bacteria are turned into tiny factories, they will begin to express and make the products of the new genes that have been added.

!  Insulin example: !  The gene for human insulin can be removed from our

DNA and placed on a plasmid, then inserted into a bacteria.

!  The bacteria will then make human insulin that scientists can collect and use to treat people with diabetes, who don’t make insulin properly on their own.

INSULIN EXAMPLE

TRANSGENIC ORGANISMS

! Genetic engineering is possible, but much more complicated in plants and animals. (p. 277)

! Transgenic Organism – an organism that has one or more genes from another organism inserted into its DNA.

! Genetically Modified Organisms (GMOs) – an organisms who's genetic material has been altered using genetic engineering techniques.

PART 4

STEM CELLS

! Stem cells are a unique type of body cell that have the ability to: !  Divide and renew themselves for long periods of time !  Remain undifferentiated in form !  Develop into a variety of specialized cells

! When a stem cells divides (mitosis), it can either replicate itself or form specialized cells.

STEM CELL DIVISION

TYPES OF STEM CELLS

! Stem cells are classified by their origin, as either adult or embryonic.

! Adult Stem Cells !  Partially undifferentiated cells located among the

specialized cells of many organs and tissues. !  Found all over the body (brain, liver, skeletal muscle) !  Advantages: they can be taken from a patient, grown

in culture, and put back into the patient with minimal risk of rejection by the immune system.

!  Disadvantages: they are few in number, hard to isolate, and tricky to grow. Considered multipotent, which means they can only give rise to closely related cells.

TYPES OF STEM CELLS

! Embryonic Stem Cells !  Most embryonic stem cells are created in labs as a

result of the formation of embryos using in vitro fertilization (process by which an egg is fertilized outside a woman’s body).

!  The stem cells are taken from a cluster of undifferentiated cells in a 3-5 day old embryo.

!  Advantages: these cells are considered pluripotent, meaning they can form any of the 200 cell types of the body. They can also be grown in culture to create an indefinite supply.

!  Disadvantages: if these cells are used in treatments, a patient’s immune system might reject them or grow unchecked created tumors. They also raise many ethical questions. This is because the most common method of getting embryonic stem cells involves the destruction of the embryo.

STEM CELL RESEARCH

! The focus of stem cell research is on the treatment of diseases.

! Stem cells have long been used to treat patients with leukemia and lymphoma (cancers).

! Example of treatment hopes: !  Patients might be cured of diabetes if non-working

cells in the pancreas were replaced with healthy, growing cells.

!  Damaged organ, like the heart, might be strengthened by an injection of healthy cells