Science Week

We have all been very busy preparing for Science Week next week!
Here are some chemistry book reviews by our senior students to help get you in the mood:

The Molecule and Its Double
Article written by: Sameer Garg

The book titled The Molecule and Its Double, talks about molecules which form mirror images. To understand what this means, we should first know that a molecule is essentially a neutral group of at least two atoms held together by covalent bonds (very strong chemical bonds). Molecules which are asymmetric, meaning they lack an internal plane of symmetry, form mirror images that appear to be the same but in actuality are not. A common example of this phenomenon is seen by looking at your left or right hand in the mirror.

(right hand in mirror) (left hand palm up)

(right hand in left hand glove)

Your left hand is the mirror image of your right hand. Also, a right hand doesn’t fit in a left hand glove.

The left and right hand appear to be symmetrical but a left hand glove doesn’t fit properly on the right hand. The problem however is not with both hands but instead with only one hand. Your hand is asymmetrical and therefore does not produce the same exact image in the mirror. The two hands are “non-superimposable mirror images” meaning that the mirror image cannot be placed on the actual hand.

In the same way at a molecular level, molecules can be “non-superimposable mirror images” also called chiral which comes from the Greek word for hand. The feature that is most often the cause of chirality in molecules is the presence of an asymmetric carbon atom. This is a carbon atom in the shape of a tetrahedral which is bonded to four different groups.

The carbon in alanine, shown below, is asymmetric meaning it is bonded to four different groups. The presence of an asymmetric carbon atom allows a molecule to exist in two forms which are mirror images of each other.

Like left and right handed gloves, the structures are not spatially equivalent to each other even though the bond sequence in these structures is the same. In conclusion, we find that molecules have doubles which are mirror images that have the same arrangement or makeup however, the structures look different.

Gaia. A new look at life on Earth.
Article written by: Elizaveta Uvarova

In my article I'm not going to present you James Lovelock as an independent scientist, environmentalist, author, researcher or Doctor Honoris Causa of several universities throughout the world. I would like to introduce James Lovelock as a creator of theory of Gaia who has a unique perspective on the fate of the earth. The idea that the earth is alive has existed since ancient times. The name Gaia (which means goddess of Earth in ancient Greek) is of a living entity and was used by Greeks two thousand years ago.

The quest for Gaia began more than 30 years ago, when NASA ( the National Aeronatics and Space Administration of the USA) first made plans to look for life on Mars. And Lovelock took part in investigation of Mars. He created a completely new concept of searching for life on other planets. To assert that life on other planets could exist only in the presence of the atmosphere and favorable climatic conditions. However, during long-term studies, he came to the conclusion that life itself affects the environment. It means that to determine the existence of life on other planets, the presence of atmospheric and climatic conditions do not have fundamental significance.

Surprisingly enough, just a search for life on other planets led him to develop a new look at life on earth. Journeys into space did more than present the Earth in a new perspective. They also sent back information about its atmoshpere and its surface which provided a new insight into the interactions between the living and the inorganic parts of the planet. From this has arisen the hypotesis, the model, in which the Earth's living matter such as air, oceans, and land surface form a complex system which can be seen as a single organism and which has the capacity to keep our planet a fit place for life.

In his book "Gaia", James Lovelok shows how life controls its own environment. For example, by controlling the level of CO2 in the atmosphere, it helps carefully maintain temperature on Earth. With increasing temperature, plants grow faster, consuming the excess CO2, which leads to a decrease in temperature. As the temperature of the Earth decreases, animals eat more plants, and the temperature again rises.

Usually, we can explain the atmospheric and climatic conditions on the planet by studying chemical processes taking place there. At the same time,this is not true on Earth. Earth over millions of years has kept the temperature at the level, conducive to the maintenance of life. Despite the bombardment of meteorites, explosions of volcanic activity and changes in solar radiation, temperature on earth remained virtually unchanged.

James noted that many scientists and other people misunderstand his Gaia hypothesis, believing that he argues that life itself is consciously and intentionally controls the environment. He just wanted to say that life affects the environment - simply acts, not necessarily intentionally.

The presence of the life makes the soil become more fertile, better ventilated and retains water. Without life, the soil eventually turns into sand. Almost all the factors of our environment are closely monitored either locally or across the planet.

All these factors, only proves once again that our planet is a single organism, in which everything is interconnected.

Gaia theory is a rich souce of prediction and in this book it was predicted that Plate tectonics might be biologically driven; that dimethyl sulphide might be the main carrier of sulphur in the natural environment; and that the forests of the humid tropics might be the areas where mankind’s destructive tendencies could do most harm.

Privileged Ape
Article written by: Daniil Levin

To begin with let’s look at the name of the book: Privileged Ape… Ape… We are Apes. Privileged, privilege is a speciality that other don’t have… Positive speciality. It is true - we are privileged. Jack Cohen searches the answers on the next questions: What is this privilege? How did we receive it? How do we keep this privilege in generations? And if there’s something negative in this privilege what is it?

Some words about the author: Jack Cohen, English, is a reproductive biologist for already twenty-five years. In addition, he has a semi-professional interest in science fiction and the myths. He worked in the University of Birmingham and, for a period, at Harvard. He wrote a lot of books on many topics, but surely, scientific, and related to the evolution. This book is not a theory; it is a new scientific viewpoint, which he hopes will generate theories.

So, let’s start with the book. The book is about the evolution, and the future, of the variety of Mankind. It contains authors developed ideas about reproduction and what is it carrying across the generations. It is all about the caring and cultural “investments” that parents make in their children. Jack Cohen intents to provide a biological context for our cultural evolution. He gives to the reader a chance to learn about different cultures, about its transmission across the generations. The book is quite difficult; well, very difficult, because this book is an outcome of biological insights generating sociological statements.

I start from evolution. Evolution is the way we change across the generations. Evolution is carried through the reproduction. We understand that a human is the most intelligent creature on our planet. It means that we have something special, that the other creatures don’t. A kind of a privilege…

So, the first question is what is our privilege? Our privilege, referring to the book, is a capability to keep the experience that we’ve earned, that our previous generations earned and to use it to gain even more experience. Our privilege is, actually, an opportunity to start developing from the place where our ancestors have stopped. We don’t have to start more or less from the beginning, as turtles, for example. Sea turtles are left on the beach in eggs and when they hatch from them, a whole new world is around, and there’s nobody to help. The main point in life is how to survive. Hunger, cold, predators are the only problems to solve out. Food, water and a place for an overnight are everything that is needed. Reproduction is not such an important feature for them.

In opposite, human offspring is born in as good conditions as possible. No hunger, no cold, no predators - no need in survival. The human baby still can’t make its own way but is “carried” through this helpless stage by adults. Why don’t we anymore have fur, claws or fangs? Why we don’t possess whose, but animals do? And instincts? All of them are forgotten, lost in history, cut from DNA. Human’s way in surviving is to think, to ask questions, to learn on our mistakes. A baby, left in deep forest will not stay alive for long.

So, in conclusion, we can say, that DNA is not the only thing that is transmitted across the human’s generations. Cultural capital is transmitted too. We also notice the different levels of organisation of life on this planet. There can be some general rules on which they depend. The bacteria grade of organisation, for example, dominated the first three quarters of Earth’s history, so far, and intelligence of our kind has been here for such a brief moment, that it is much more difficult to pick out “likelihoods” rather then just to accept it as a matter of chance?

Jack Cohen asks himself interesting questions, like “What passes between the generations to reproduce a Frenchman?” The answer is genetic and cultural inputs. Both are required. The middle chapters examine the enormous and apparent, cultural and material success of urban life from this reproductive viewpoint. Cities, for example, are immensely effective accumulators and transmitters of this human cultural capital. New York, for example is balanced by its differences of culture, rather by the lowest-common-denominator philosophy of its political wards or educational establishment. Islam or democracy or communism could each prevent the attainment of a culture, which permits all of them to flourish.

After that, Dr. Cohen slowly moves into different cultures and the relations between them. He gives in example of what happens between them: “The girl growing in an Islamic enclave within a European city is taught to be sexually attractive but not available, while her school-friends in the majority culture take the converse solution to the social equation: they are available but not (in her terms) attractive.”