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The first attempt in cloning was conducted in 1952 on a group of frogs.
The experiment was a partial success. The frog cells were cloned into other
living frogs however, only one in every thousand developed normally , all of
which were sterile. The rest of the frogs that survived grew to abnormally large
sizes. In 1993, scientist and director of the in vitro lab at George
Washington University, Jerry Hall and associate Robert Stillman, reported the
first ever successful cloning of human embryos. It was the discovery of in-
vitro fertilization in the 1940's that began the pursuit to ease the suffering
of infertile couples. After years of research, scientists learned that "in a
typical in-vitro procedure, doctors will insert three to five embryos in hopes
that, at most, one or two will implant" (Elmer-Dewitt 38). And that "a woman
with only one embryo has about a 10% to 20% chance of getting pregnant through
in-vitro fertilization. If that embryo could be cloned and turned into three or
four, thechances of a successful pregnancy would increase significantly"(Elmer-
Dewitt 38).
The experiment the scientists performed is the equivalent of a mother
producing twins. The process has been practiced and almost perfected in
livestock for the past ten years, and some scientists believe that it seems only
logical that it would be the next step in in-vitro fertilization. The procedure
was remarkably simple. Hall and Stillman "selected embryos that were abnormal
because they came from eggs that had been fertilized by more than one sperm"
(Elmer-Dewitt 38), because the embryos were defective, it would have been
impossible for the scientist to actually clone another person. They did however,
split the embryos into separate cells, as a result creating separate and
identical clones. They began experimenting on seventeen of the defective
embryos and "when one of those single-celled embryos divided into two cell'the
scientists quickly separated the cells, creating two different embryos with the
same genetic information" (Elmer-Dewitt 38). The cells are coated with a
protective covering "called a zona pellucida, that is essential to development"
(Elmer-Dewitt 38), which was stripped away and replaced with a gel-like
substance ...
Newton's Method is used to find the root of an equation provided that the function f[x] is equal to zero. Newton Method is an equation created before the days of calculators and was used to find approximate roots to numbers. The roots of the function are where the function crosses the x axis. The basic principle behind Newton's Method is that th...
Hard Boiled eggs Place dozen eggs in large pot and fill with enough water to cover eggs. Bring eggs to boil, remove from heat, cover, and let sit for 20 minutes. Gently and carefully remove eggs from hot water, and place in bowl. Run cold tap water over eggs to cool off. ________________________________________ Non-boiled egg prep Gently ta...
The heart is bestowed with a specialized system that automatically generates rhythmic control via the sinus node, located in the superior lateral wall of the right atrium near the opening of the superior vena cava. The specialized pacemaker cells dictate control of the rest of the heart through regular electrical impulses that propagate from the r...
are objects so dense that not even light can escape their gravity, and since nothing can travel faster than light, nothing can escape from inside a black hole . Loosely speaking, a black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull. Since our best theory...
There are many beaches in the world ,which one you would like to visit ? Each one has its own characteristics in architecture ,the way of its people ,landscape,etc. For me ,Nha Trang is the best beach in my heart .Nha Trang beach has lots of wonderful sight that can help me reduce stress after work and school.i used to go there one a month when I...
