Docstoc

The Basics of Cloning

Document Sample
The Basics of Cloning Powered By Docstoc
					The Basics of Cloning

      What Cloning Is
     Stem Cell Research
    The Good and the Bad
        Legal Stuff
        What is Cloning?

Cloning is the process of making a
genetically identical organism through
nonsexual means.


In your own words, what does this
mean?
                  What is
                  Cloning?

Basically, cloning is creating one
organism from another organism that
already exists.
The organisms have identical DNA
This means that they look the same
         What is Cloning?
BUT—these identical
twins look the same
and have the same
DNA, so are they
clones???

Why???
    How do we get clones?
Clones are created when a cell (with its
  DNA) is placed into an egg cell that
  has had its DNA removed.
Cloning can be used to produce animals
  or plants with desired
  characteristics.
     How Dolly was cloned




1. A donor egg had its nucleus removed
2. A cell (containing DNA) was taken from
   the sheep that was being cloned
     How Dolly was cloned

3. The cell and the donor egg were
    fused using electricity
4. This created an embryo
5. This embryo was implanted in the
    uterus of a surrogate mother
    (sheep) for nine months
     How Dolly was cloned
6.   The surrogate mom gives birth to
     a clone!
7.   Is the clone from the egg or the
     cell with DNA???
8.   This procedure is not very
     successful—it took 277 tries to
     get Dolly!
     How do we get clones?
Some cloning is made possible through the
use of stem cells.




One important kind of stem cell is called an
embryonic stem cell.
            Stem Cells
Each person begins life as a single cell
  called a zygote, which begins to
  divide.
After about 5 days, it becomes a mass
  of cells called a blastocyst.
Inside the blastocyst there is an inner
  layer where the stem cells are found.
Where stem cells are found
            Stem Cells
Stem cells are especially important for
   two reasons:
1. They are unspecialized—they do not
   have a particular role in the human
   body.
2. BUT—they can be given a role to
   play through certain chemical
   factors.
            Stem Cells
Stem cells are pluripotent

This means they are capable of
 developing into any cell type in the
 human body such as heart, skin or
 hair.
             Stem Cells
Today, some people want to take those
 unspecialized stem cells and give
 them certain roles.

Doctors can potentially take stem cells
 and induce them into a specific cell,
 for example, a nerve cell or blood cell.
     Stem cells—so what?
Taking stem cells and creating a
 specific cell can lead to good and bad
 things.
This creates ethical problems for most
 people—is cloning good or bad?
                   Cloning—good?
Cloning can lead to very beneficial things like:
1. A cure for diseases such as Parkinson’s,
    Alzheimer's, or diabetes
2. It can help people who have fertility
    problems have biological children (but
    they would be clones of one of the
    parents!)
3. Further research cures for other
    diseases
          Cloning—bad?
Cloning also raises some ethical and
   biological problems:
1. It decreases the gene pool (more
   people with the same DNA)
2. Cloning is unnatural—the clone would
   not be an “original” person
3. It eliminates the need for men!
   (How???)
Therapeutic Cloning—maybe
      the first step

A person’s own DNA is used to grow a
 clone.
But instead of planting this embryo into
 a uterus to become a baby, its stem
 cells are removed and grown in a
 Petri dish
Therapeutic Cloning—maybe
      the first step


They use the stem cells to create the
 cells that are needed, such as nerve
 cells to treat Parkinson’s Disease, or
 even to grow replacement organs such
 as hearts!
Therapeutic Cloning
Therapeutic Cloning
              Legal Stuff
In August 2001, President Bush
  announced the government’s legal
  stance on cloning:
• Federal funds can be used for stem
  cell research
• But only existing cell lines could be
  used (no new cells could be created,
  thus no therapeutic cloning)
           Legal Stuff
BUT—privately funded stem cell
 research (even human cloning) is okay

In Great Britain, any stem cell
  research, as well as therapeutic
  cloning, is okay. However, human
  cloning (to make a new person) is NOT
  okay.
    What do you think???
          Think, Pair, Share

If you were a lawmaker, would you make
   cloning legal or not?
What conditions would you have (like no
   human cloning)?
     What do you think???
           Think, Pair, Share
1. Think about your stance for one
   minute
2. Share your view with a partner at
   your table and explain why you feel
   that way
3. Each of you be prepared to share
   your view with the class

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:8
posted:8/29/2012
language:English
pages:27