Professor Susan Greenfield, director of the Royal Institution in London, debates the future of science. BBC News Online Science Correspondent David Whitehouse reports.

Earth: under scrutiny

Flexible minds will be needed to cope with the fall-out of the advances in physics, chemistry, and biology, says Professor Greenfield.

She paints a not altogether attractive picture of scientific advances during the next century, stressing the many roles that science plays in society.

There is science for discovering things like the fate of the universe and the fundamental structure of space and time.

And there is science that provides tangible benefits.

Shape and size

Many of these improvements will come in the shape of new materials. "They are the very essence of technological progress," says Professor Greenfield.

"In the future we will have new catalysts, new composites, and compounds that mimic the greatest inventor - Nature."

Making things smaller will also be important. This is called nanoscience - making objects and structures about a millionth of a millimetre in size.

Electricity will power smaller machines

"Even today, mechanical and electrical devices can be made from a single molecule, and wires can be a single atom wide. In the next century, electrical circuits will be at least 100 times smaller than current ones, and machines, including those for surgery, will be on this small scale."

She emphasises that the power of the science of molecular biology will affect us all.

We will learn more about genes and how they work. We will decode the entire genetic blueprints of many organisms.

But many of our pressing problems will not be solved by understanding genetics alone. A good example is the problem of combating Alzheimer's disease.

This devastating disorder - characterised by mounting confusion, memory loss, and disintegration of the individual's mind - has no single cause.

"However, a safe prediction might be that genetic disorders, such as cystic fibrosis, thalassemia, and Huntington's chorea will be eradicated," says Professor Greenfield.

The power of medicine

Trying to discover how the brain generates consciousness will also come to the fore. For many, this is the ultimate conundrum for science to unravel.

Professor Greenfield says it touches on the very nature of our most private and personal place - that inner world that no-one else can hack into.

Dolly the cloned sheep: Could humans be next?

"Germ-line therapy - the manipulation of genes we pass down to future generations - is currently banned, but could well become a reality."

But she warns: "As we learn more about controlling and selecting our genes, there is a real threat that we will strive to conform to a particular physical standard of fitness and beauty. Nowhere is this prospect more threatening than with cloning."

Already the popular press is spreading alarm at the idea of mini armies of identical children being bred.

Such an assumption belies a shaky grasp of what genes actually do. It is important to realise that genes are not omnipotent, but only work within a given context.

The multimedia age

With the sheer volume of information bombarding our brains, we may lose sight of something valuable - our imagination.

"One possible consequence will be that as our attention span falls so our imagination will dwindle. We might become a society hooked on sensually-laden multimedia, unable to concentrate and hence to think," says Professor Greenfield.

The way forward: Glued to the multimedia screen

But there are also dangers in trying to combat threats arising from science in the future. One of these is sensationalism in the media.

She says: "The result is that the public are unduly panicked, insufficiently informed, and view scientists as nerds or power-crazed robotic megalomaniacs."

To overcome this, Professor Greenfield says we should change journalists' "mind-set" in favour of giving their readers, listeners and viewers an in-depth review of a subject.

"Above all, it is important to combat the fear and prejudice arising from incomplete information among the public.

"Not only must we aim for a scientifically literate society, but one where the public, now armed with all this knowledge, can air their views in front of the experts and legislators."