BBC Learning English. Part 5 – Cloning

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BBC Learning English

Part 5 – Cloning

We are all made from billions of cells, and at the centre of each one are the instructions - the ______________ - for building our bodies which is stored in the form of a chemical called DNA.
There are two types of cloning, ___________________________ where a new baby would be created or ________________________, that’s about copying just some of the cells. Therapeutic cloning concentrates on some special cells called _____________ - they’re the powerfully adaptable 'master cells'.
These cells exist naturally in the body and they are there to replace cells that are lost through natural processes, so you lose ________________ all the time, you lose cells from your ____________ – your guts - and there are stem cells in the brain to replace a few cells which are lost.
…in the cases where there's accidental damage or a disease which ________________________, then quite frequently the stem cells aren't able to divide fast enough to replace the damaged tissue. So it's hoped that by growing them in a ___________, if you like, that they can be now used to replace lost cells in a person.
As Dr Robin Lovell-Badge explained, __________________________. They repair and maintain our _____________________ and other organs.
In 1998, American scientists succeeded in ________________________ – growing – stem cells. They ____________________________ for medical research and treatment.
In Sweden, for example, the neural cells - cells taken from the brain of adult mice – have been used to ______________________________. But researchers aren’t sure whether adult stem cells are as _________________________ as those found in _______________ - newly created lives.
When an egg is _________________ by a sperm, it forms a ball of cells, any of them can develop into almost any cell in the body.
Why is the procedure causing so much anxiety? Well, one way of _______________ – collecting - stem cells is to actually create embryos, through a process known as therapeutic cloning.
Dolly was the first _______________ cloned from an adult cell - a nucleus taken from an adult sheep cell and inserted into an empty egg. The egg's development into an embryo was _______________ by a revolutionary new technique which makes it possible to clone existing animals…
Once we have perfect copies of ourselves we’ll be able to repair and ___________________________. The ____________________________ we have now sometimes fail…
…our bodies work hard to reject anything alien that is _________________ onto it – anything that is imported into the body, even if it’s a new lung, a liver or a new heart.
In Britain, ________________________________ fall from 81% in the first year to 65% of patients surviving five years after the operation.
So the patient’s body would then accept stem cells which perfectly matched his __________________ instead of ___________________________________ or a tissue graft. In future cell nuclear transfer could even be used to create a ____________________________ …
. Some of the _____________________________ of the 21st century may result from stem cell research. The development and _________________________________ will attract the attention of the world’s media for some time to come.
Should the cloning of human embryos be permitted, even if reproductive cloning, the creation and birth of cloned human beings, is _______________?
…stem cells have an enormous potential to create new forms of treatment for diseases which are ___________________________
The committee say that the ____________________________________. They believe research should continue, should go forward, but only if strict rules limit, or regulate, the research.

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