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scienceyoucanlove:

How Cloning Works


On Jan. 8, 2001, scientists at Advanced Cell Tec­hnology, Inc., announced the birth of the first ­clone of an endangered animal, a baby bull gaur (a large wild ox from India and southeast Asia) named Noah. Although Noah died of an infection unrelated to the procedure, the experiment demonstrated that it is possible to save endangered species through cloning.

Cloning is the process of making a genetically identical organism through nonsexual means. It has been used for many years to produce plants (even growing a plant from a cutting is a type of cloning).

Animal cloning has been the su­bject of scientific experiments for years, but garnered little attention until the birth of the first cloned mammal in 1996, a sheep named Dolly. Since Dolly, several scientists have cloned other animals, including cows and mice. The recent success in cloning animals has sparked fierce debates among scientists, politicians and the general public about the use and morality of cloning plants, animals and possibly humans.

In this article, we will examine how cloning works and look at possible uses of this technology.

The unfer­tilized eggs of some animals (small invertebrates, worms, some species of fish, lizards and frogs) can develop into full-grown adults under certain environmental conditions — usually a chemical stimulus of some kind. This process is called parthenogenesis, and the offspring are clones of the females that laid the eggs.

Another example of natural cloning is identical twins. Although they are genetically different from their parents, identical twins are naturally occurring clones of each other.

Scientists have experimented with animal cloning, but have never been able to stimulate a specialized (differentiated) cell to produce a new organism directly. Instead, they rely on transplanting the genetic information from a specialized cell into an unfertilized egg cell whose genetic information has been destroyed or physically removed.

In the 1970s, a scientist named John Gurdon successfully cloned tadpoles. He transplanted the nucleus from a specialized cell of one frog (B) into an unfertilized egg of another frog (A) in which the nucleus had been destroyed by ultraviolet light. The egg with the transplanted nucleus developed into a tadpole that was genetically identical to frog B.

While Gurdon’s tadpoles did not survive to grow into adult frogs, his experiment showed that the process of specialization in animal cells was reversible, and his technique of nuclear transfer paved the way for later cloning successes.

Dolly

In 1996, cloning was revolutionized when Ian Wilmut and his colleagues at the Roslin­ Institute in Edinburgh, Scotland, successfully cloned a sheep named Dolly. Dolly was the first cloned mammal.

Wilmut and his colleagues transplanted a nucleus from a mammary gland cell of a Finn Dorsett sheep into the enucleated egg of a Scottish blackface ewe. The nucleus-egg combination was stimulated with electricity to fuse the two and to stimulate cell division. The new cell divided and was placed in the uterus of a blackface ewe to develop. Dolly was born months later.

Dolly was shown to be genetically identical to the Finn Dorsett mammary cells and not to the blackface ewe, which clearly demonstrated that she was a successful clone (it took 276 attempts before the experiment was successful). Dolly has since grown and reproduced several offspring of her own through normal sexual means. Therefore, Dolly is a viable, healthy clone.

Since Dolly, several university laboratories and companies have used various modifications of the nuclear transfer technique to produce cloned mammals, including cows, pigs, monkeys, mice and Noah.

read more about Dolly and cloning 

Thank you for sharing us, scienceyoucanlove!

thatscienceguy
wildcat2030:

A Neuroscientist’s Radical Theory of How Networks Become Conscious
It’s a question that’s perplexed philosophers for centuries and scientists for decades: Where does consciousness come from? We know it exists, at least in ourselves. But how it arises from chemistry and electricity in our brains is an unsolved mystery. Neuroscientist Christof Koch, chief scientific officer at the Allen Institute for Brain Science, thinks he might know the answer. According to Koch, consciousness arises within any sufficiently complex, information-processing system. All animals, from humans on down to earthworms, are conscious; even the internet could be. That’s just the way the universe works. “The electric charge of an electron doesn’t arise out of more elemental properties. It simply has a charge,” says Koch. “Likewise, I argue that we live in a universe of space, time, mass, energy, and consciousness arising out of complex systems.” What Koch proposes is a scientifically refined version of an ancient philosophical doctrine called panpsychism — and, coming from someone else, it might sound more like spirituality than science. But Koch has devoted the last three decades to studying the neurological basis of consciousness. His work at the Allen Institute now puts him at the forefront of the BRAIN Initiative, the massive new effort to understand how brains work, which will begin next year. Koch’s insights have been detailed in dozens of scientific articles and a series of books, including last year’s Consciousness: Confessions of a Romantic Reductionist. WIRED talked to Koch about his understanding of this age-old question. (via A Neuroscientist’s Radical Theory of How Networks Become Conscious - Wired Science)

wildcat2030:

A Neuroscientist’s Radical Theory of How Networks Become Conscious

It’s a question that’s perplexed philosophers for centuries and scientists for decades: Where does consciousness come from? We know it exists, at least in ourselves. But how it arises from chemistry and electricity in our brains is an unsolved mystery. Neuroscientist Christof Koch, chief scientific officer at the Allen Institute for Brain Science, thinks he might know the answer. According to Koch, consciousness arises within any sufficiently complex, information-processing system. All animals, from humans on down to earthworms, are conscious; even the internet could be. That’s just the way the universe works. “The electric charge of an electron doesn’t arise out of more elemental properties. It simply has a charge,” says Koch. “Likewise, I argue that we live in a universe of space, time, mass, energy, and consciousness arising out of complex systems.” What Koch proposes is a scientifically refined version of an ancient philosophical doctrine called panpsychism — and, coming from someone else, it might sound more like spirituality than science. But Koch has devoted the last three decades to studying the neurological basis of consciousness. His work at the Allen Institute now puts him at the forefront of the BRAIN Initiative, the massive new effort to understand how brains work, which will begin next year. Koch’s insights have been detailed in dozens of scientific articles and a series of books, including last year’s Consciousness: Confessions of a Romantic Reductionist. WIRED talked to Koch about his understanding of this age-old question. (via A Neuroscientist’s Radical Theory of How Networks Become Conscious - Wired Science)

science-junkie

wildcat2030:

See on Scoop.it - The future of medicine and health
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This week, health authorities in New Zealand announced that the tightly quarantined island nation — the only place I’ve ever been where you get x-rayed on the way into the country as well as leaving it — has…

thatscienceguy
thenewenlightenmentage:

An Interactive Map Of The Brain
Time to play “name that cortex.”
Can you point out the small squiggle of gray matter that makes up the brain’s motor cortex? Or how about the eye fields, which control visual attention and eye movements? No? Take a look at this handy interactive infographic created by Open Colleges, an Australian online education company, which walks you through major parts of the brain and what they control.
It maps out different regions of the brain like the frontal lobes or the neo cortex, what processes they deal with and how studies have shown that region to impact learning. The graphic has three views: the cerebral cortex, the outer layer of the brain involved in a whole host of functions like sensory perception, motor control and learning; the limbic system, a group of structures that deals with emotion and behavior; and the neuron, the individual cells that transmit chemical messages throughout the nervous system. Within those tabs, you can explore deeper to learn about specific aspects of each structure, like the role of dopamine or the functions controlled by the occipital lobe.
Go ahead and play around with it.

thenewenlightenmentage:

An Interactive Map Of The Brain

Time to play “name that cortex.”

Can you point out the small squiggle of gray matter that makes up the brain’s motor cortex? Or how about the eye fields, which control visual attention and eye movements? No? Take a look at this handy interactive infographic created by Open Colleges, an Australian online education company, which walks you through major parts of the brain and what they control.

It maps out different regions of the brain like the frontal lobes or the neo cortex, what processes they deal with and how studies have shown that region to impact learning. The graphic has three views: the cerebral cortex, the outer layer of the brain involved in a whole host of functions like sensory perception, motor control and learning; the limbic system, a group of structures that deals with emotion and behavior; and the neuron, the individual cells that transmit chemical messages throughout the nervous system. Within those tabs, you can explore deeper to learn about specific aspects of each structure, like the role of dopamine or the functions controlled by the occipital lobe.

Go ahead and play around with it.