scientists like to actually see the things they research. but this isn't always possible

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Scientists like to actually see the things they research. But this isn't always possible. Source: Clipart ETC. Most of what we see is larger than the wavelength of visible light. Scientists occasionally want to study things that are smaller than the wavelength of visible light. - PowerPoint PPT Presentation

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Page 1: Scientists like to actually see the things they research.  But this isn't always possible
Page 2: Scientists like to actually see the things they research.  But this isn't always possible

Scientists like to actually see the things they research .

But this isn't always possible.

Source: Clipart ETC

Page 3: Scientists like to actually see the things they research.  But this isn't always possible

Source: Wikipedia

Most of what we see is larger than the wavelength of visible light.

Scientists occasionally want to study things that are smaller thanthe wavelength of visible light.

Wavelength of ultraviolet light: 400 nanometersOne nanometer = one millionth of a millimeter

Page 4: Scientists like to actually see the things they research.  But this isn't always possible

That was the case with the ribosome that Nobel Prize laureate Prof. Ada Yonath wanted to explore.

The diameter of a ribosome is about 20 nanometers, which is approximately 20 times smaller than the ultraviolet wavelength.

Wavelength of ultraviolet light: 400 nanometersOne nanometer = one millionth of a millimeter

Page 5: Scientists like to actually see the things they research.  But this isn't always possible

To "see" the internal structure of bodies the size of a ribosome, scientists often expose them to x-rays.

This reveals the location of single atoms.

The wavelength of x-rays is about 20 times smaller than the diameter of ribosomes.

Source: NASA

Page 6: Scientists like to actually see the things they research.  But this isn't always possible

The ribosome is a key component of living cells.

Source: Wikipedia

Page 7: Scientists like to actually see the things they research.  But this isn't always possible

Living cells have a single nucleus and thousands of ribosomes.

Source: Wikipedia

Page 8: Scientists like to actually see the things they research.  But this isn't always possible

Ribosomes translate the genetic information within the cell's nucleus into a process for producing proteins.

Source Wikipedia

Page 9: Scientists like to actually see the things they research.  But this isn't always possible

Proteins are huge molecules, structured like folding chains and composed of a sequence of amino acids.

Source: Wikipedia

Page 10: Scientists like to actually see the things they research.  But this isn't always possible

Proteins are one of the most important compounds that make up living organisms. They are found in every living cell.

Ribosomes themselves are composed, in part, of proteins

Source: Clipart ETC

Page 12: Scientists like to actually see the things they research.  But this isn't always possible

The method for determining the structure of biological molecules using radiation is called x-ray crystallography.

Prof. Ada Yonath uses x-ray crystallography to study ribosomes.

Source NASA

Page 13: Scientists like to actually see the things they research.  But this isn't always possible

To prepare a living substance for x-ray crystallography research, the substance itself needs to be crystallized.

Source: Prof' Ada Yonaths' Lab

Page 14: Scientists like to actually see the things they research.  But this isn't always possible

Different crystals diffract the x-rays directed at them in different ways.

The particular composition and spatial structure of each crystal create a unique picture.

This picture resembles a collection of dots.

Source: Wikipedia

Page 15: Scientists like to actually see the things they research.  But this isn't always possible

All the pictures created during x-raying are entered into powerful computers, which feed them into a complex decoding process resulting in three-dimensional images.

The computer-assisted decoding relies on mathematical formulas and hypothetical structural models, based on data gathered through other methods.

Source: Wikipdia

Page 16: Scientists like to actually see the things they research.  But this isn't always possible

As the x-raying proceeds, it is crucial to maintain the stability of the substance being examined. In many cases, the substance is deformed due to the strong radiation it receives, similar to the way living tissues are harmed in an X-ray test.

Because of the radiation, the substance changes form, preventing the researcher from determining its structure.

Page 17: Scientists like to actually see the things they research.  But this isn't always possible

Prof. Ada Yonath was the first to deal successfully with two complex problems: crystallizing the ribosome and preparing the crystal for x-ray without changing its form during the examination process.

Source: L'OREAL-UNESCO Awards For Women in Science

Page 18: Scientists like to actually see the things they research.  But this isn't always possible

The living substance that Prof. Yonath used to examine ribosome structure was bacteria that live in hot springs or in the Dead Sea, which are resistant to high temperatures.

Prof. Yonath cooled samples of the substance to a temperature of -185º C, preventing its decomposition under experimental conditions.

Page 19: Scientists like to actually see the things they research.  But this isn't always possible

This accomplishment earned her the 2009 Nobel Prize for Chemistry.

She shared the prize with Thomas Steitz of Yale University in the U.S. and Venkatraman Ramakrishnan of Cambridge University in Britain.

The three scientists were awarded the prize for their contribution to the study of ribosome structure and functioning.

Page 20: Scientists like to actually see the things they research.  But this isn't always possible

Most antibiotic medicines attach themselves to bacterial ribosomes, preventing them from acting.

By understanding how antibiotics affect ribosomes, scientists can conduct research leading to the development of more effective drugs.

Source: The lab of Prof' Ada Yonath

Page 21: Scientists like to actually see the things they research.  But this isn't always possible

Writing: Hanan CohenEditing: Nurit SnirGraphic design: Vadik Bakman

Many thanks to Prof. Ada Yonath for her comments on this presentation