• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

CLONING - Discusion

Extracts from this document...

Introduction

CLONING The possibility of human cloning, raised when Scottish scientists at Roslin Institute created the much-celebrated sheep "Dolly", created worldwide interest and concern because of its scientific and ethical implications. The feat, cited by Science magazine as the breakthrough of 1997, also generated uncertainty over the meaning of "cloning" a term traditionally used by scientists to describe different processes for duplicating biological material. When the media report on cloning in the news, they are usually talking about only one type called reproductive cloning. There are different types of cloning however, and cloning technologies can be used for other purposes besides producing the genetic twin of another organism. A basic understanding of the different types of cloning is important to taking an informed stance on current public policy issues and making the best possible personal decisions. The following three types of cloning technologies will be discussed: a) recombinant DNA technology or DNA cloning, b) ...read more.

Middle

coli cells. BACs utilize the naturally occurring F-factor plasmid found in E. coli to carry 100 to 300 kb DNA inserts. A YAC is a functional chromosome derived from yeast that can carry up to 1 MB of foreign DNA. Bacteria are most often used as the host cells for recombinant DNA molecules, but yeast and mammalian cells also are used. Reproductive cloning is a technology used to generate an animal that has the same nuclear DNA as another currently or previously existing animal. Dolly was created by reproductive cloning technology. In a process called "somatic cell nuclear transfer" (SCNT), scientists transfer genetic material from the nucleus of a donor adult cell to an egg whose nucleus, and thus its genetic material, has been removed. The reconstructed egg containing the DNA from a donor cell must be treated with chemicals or electric current in order to stimulate cell division. Once the cloned embryo reaches a suitable stage, it is transferred to the uterus of a female host where it continues to develop until birth. ...read more.

Conclusion

Stem cells are extracted from the egg after it has divided for 5 days. The egg at this stage of development is called a blastocyst. The extraction process destroys the embryo, which raises a variety of ethical concerns. Many researchers hope that one day stem cells can be used to serve as replacement cells to treat heart disease, Alzheimer's, cancer, and other diseases. In November 2001, scientists from Advanced Cell Technologies (ACT), a biotechnology company in Massachusetts, announced that they had cloned the first human embryos for the purpose of advancing therapeutic research. To do this, they collected eggs from women's ovaries and then removed the genetic material from these eggs with a needle less than 2/10,000th of an inch wide. A skin cell was inserted inside the enucleated egg to serve as a new nucleus. The egg began to divide after it was stimulated with a chemical called ionomycin. The results were limited in success. Although this process was carried out with eight eggs, only three began dividing, and only one was able to divide into six cells before stopping. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Genetics, Evolution & Biodiversity section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Genetics, Evolution & Biodiversity essays

  1. Marked by a teacher

    An Investigation into the Mitotic Nuclear Division of Allium Sativum Root Tip Cells, and ...

    5 star(s)

    forces of the microtubule spindle fibres; a process that has a low energetic requirement. Hence, the cell counts observed are in accordance with those predicted in the hypotheses, and those obtained during research, demonstrating the regularity of the metaphase duration throughout numerous sets of data and therefore experimental investigations.

  2. Marked by a teacher

    Human Cloning Assignment

    4 star(s)

    It can also result in multiple pregnancies. Cloning is only another alternative to reproduction and unlike IVF; it takes very few cells and should work the first time with a single pregnancy making it a more efficient method of reproduction.

  1. Marked by a teacher

    The daphnia lab report

    3 star(s)

    To get the number of beats per minute the heart beats were multiplied by 4. 9. Step 5-8 were repeated for the other five solutions using a new daphnia every time and from each caffeine concentration, heart rate (bpm)

  2. Recombinant DNA, genetically engineered DNA prepared in vitro by cutting up DNA molecules and ...

    During sex cell division, however, an important gene exchange between homologous chromosomes takes place. Linked Nonalleles and Crossing Over As meiosis takes place, homologous chromosomes exchange some of their genes. This phenomenon is known as crossing over. Although the process is not well understood, it is thought that a reciprocal

  1. Chromosomes and DNA

    This exercise will remind you how nitrogen is converted into different forms before being used and excreted by plants and animals. Nitrogen must be changed into a more reactive form to allow plants and animals to use it. Plants can take up and use nitrogen when it is in the form of nitrates or ammonium salts.

  2. DNA cloning or gene cloning

    Many people are very opposed to cloning humans. The U.S. Congress has passed a bill to ban human cloning which would make it a crime to even attempt human cloning and to ship, receive or import cloned embryos or products derived from them. Many people feel that it is unethical and immoral to clone humans.

  1. Oncogenes are genes that cause cancer.

    Vogt of the University of Southern California. The strains are "deletion" mutants that have lost the oncogene and are therefore incapable of inducing tumors or transforming cells in culture. Duesberg and Weissmann and his colleagues fragmented the genomes of deletion mutants and of wild-type (oncogenic) viruses with the enzyme ribonuclease.

  2. patterns of growth and development

    from different distances, recognise colours and to control the movements of their eyes and use both of the eyes together. Babies eyes are examined soon after birth to make sure there are no eye problems. They go through different stages and progress through each.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work