chemistry

In the 21st century our tastes buds, our brain chemistry, our biochemistry, our hormones and our kitchens have been hijacked by the food industry.

I really enjoyed hanging out with some of the teachers. This one chemistry teacher, she liked hanging out. I liked making explosives. We would stay after school and blow things up.

Almost all the world is natural chemicals, so it really makes you re-think everything. A cup of coffee is filled with chemicals. They've identified a thousand chemicals in a cup of coffee. But we only found 22 that have been tested in animal cancer tests out of this thousand. And of those, 17 are carcinogens. There are ten milligrams of known carcinogens in a cup of coffee and thats more carcinogens than you're likely to get from pesticide residues for a year!

The chemists who uphold dualism are far from being agreed among themselves; nevertheless, all of them in maintaining their opinion, rely upon the phenomena of chemical reactions. For a long time the uncertainty of this method has been pointed out: it has been shown repeatedly, that the atoms put into movement during a reaction take at that time a new arrangement, and that it is impossible to deduce the old arrangement from the new one. It is as if, in the middle of a game of chess, after the disarrangement of all the pieces, one of the players should wish, from the inspection of the new place occupied by each piece, to determine that which it originally occupied.

[Henry Cavendish] fixed the weight of the earth; he established the proportions of the constituents of the air; he occupied himself with the quantitative study of the laws of heat; and lastly, he demonstrated the nature of water and determined its volumetric composition. Earth, air, fire, and water__ach and all came within the range of his observations.

For the first time I saw a medley of haphazard facts fall into line and order. All the jumbles and recipes and hotchpotch of the inorganic chemistry of my boyhood seemed to fit into the scheme before my eyes__s though one were standing beside a jungle and it suddenly transformed itself into a Dutch garden.[Upon hearing the Periodic Table explained in a first-tern university lecture.]

I wasn__ aware of just how close he__ moved to me until now. So many details came into focus. The shape of his lips, the line of his neck. ____ not dangerous,_ I breathed.He brought his face toward mine. __ou are to me.__nd somehow, against all reason, we were kissing. I closed my eyes, and the world around me faded. The noise, the smoke_._._. it was gone. All that mattered was the taste of his mouth, a mix of cloves and mints. There was a fierceness in his kiss, a desperation_._._. and I answered, just as hungry for him. I didn__ stop him when he pulled me closer, so that I almost sat on his lap. I__ never been wrapped around someone__ body like that, and I was shocked at how eagerly mine responded. His arm went around my waist, pulling me onto him further, and his other hand slid up the back of my neck, getting entangled in my hair. He took his lips away from my mouth, gently trailing kisses down to my neck. I tipped my head back, gasping when the intensity returned to his mouth. There was an animalistic quality that sent shock waves through the rest of my body.

Attraction isn't wrong. People can__ help who they are drawn to and they certainly can__ control affinity, as uncommon as it is. What is wrong is acting on inclination if it hurts someone else, namely a significant other.

If the results of the present study on the chemical nature of the transforming principle are confirmed, then nucleic acids must be regarded as possessing biological specificity the chemical basis of which is as yet undetermined.

In describing a protein it is now common to distinguish the primary, secondary and tertiary structures. The primary structure is simply the order, or sequence, of the amino-acid residues along the polypeptide chains. This was first determined by [Frederick] Sanger using chemical techniques for the protein insulin, and has since been elucidated for a number of peptides and, in part, for one or two other small proteins. The secondary structure is the type of folding, coiling or puckering adopted by the polypeptide chain: the a-helix structure and the pleated sheet are examples. Secondary structure has been assigned in broad outline to a number of librous proteins such as silk, keratin and collagen; but we are ignorant of the nature of the secondary structure of any globular protein. True, there is suggestive evidence, though as yet no proof, that a-helices occur in globular proteins, to an extent which is difficult to gauge quantitatively in any particular case. The tertiary structure is the way in which the folded or coiled polypeptide chains are disposed to form the protein molecule as a three-dimensional object, in space. The chemical and physical properties of a protein cannot be fully interpreted until all three levels of structure are understood, for these properties depend on the spatial relationships between the amino-acids, and these in turn depend on the tertiary and secondary structures as much as on the primary. Only X-ray diffraction methods seem capable, even in principle, of unravelling the tertiary and secondary structures.[Co-author with G. Bodo, H. M. Dintzis, R. G. Parrish, H. Wyckoff, and D. C. Phillips]

As the physicist Paul Davies puts it, 'If everything needs everything else, how did the communities of molecules ever arise in the first place?' It is rather as if all the ingredients in your kitchen somehow got together and baked themselves into a cake - but a cake that could moreover divide when necessary to produce more cakes. It is little wonder that we call it the miracle of life. It is also little wonder that we have barely begun to understand it.

My laboratory is interested in the related challenges of understanding the origin of life on the early earth, and constructing synthetic cellular life in the laboratory. Focusing on artificial life frees us to explore novel chemical systems, but what we learn from these systems helps us to understand possible pathways leading to the origin of life. Our basic design for a synthetic cell involves the encapsulation of a spontaneously replicating nucleic acid, which acts as the genetic material, within a spontaneously replicating membrane vesicle, which provides spatial localization. We are using chemical synthesis to make nucleic acids with modified nucleobases and sugar-phosphate backbones.

A DNA sequence for the genome of bacteriophage ΦX174 of approximately 5,375 nucleotides has been determined using the rapid and simple 'plus and minus' method. The sequence identifies many of the features responsible for the production of the proteins of the nine known genes of the organism, including initiation and termination sites for the proteins and RNAs. Two pairs of genes are coded by the same region of DNA using different reading frames.

The cell, this elementary keystone of living nature, is far from being a peculiar chemical giant molecule or even a living protein and as such is not likely to fall prey to the field of an advanced chemistry. The cell is itself an organism, constituted of many small units of life.

For it is not cell nuclei, not even individual chromosomes, but certain parts of certain chromosomes from certain cells that must be isolated and collected in enormous quantities for analysis; that would be the precondition for placing the chemist in such a position as would allow him to analyse [the hereditary material] more minutely than [can] the morphologists ... For the morphology of the nucleus has reference at the very least to the gearing of the clock, but at best the chemistry of the nucleus refers only to the metal from which the gears are formed.

Chloroplasts bear chlorophyll; they give the green world its color, and they carry out the business of photosynthesis. Around the inside perimeter of each gigantic cell trailed a continuous loop of these bright green dots. They spun . . . they pulsed, pressed, and thronged . . . they shone, they swarmed in ever-shifting files around and around the edge of the cell; they wandered, they charged, they milled, raced . . . they flowed and trooped greenly . . . All the green in the planted world consists of these whole, rounded chloroplasts . . . If you analyze a molecule of chlorophyll itself, what you get is one hundred thirty-six atoms of hydrogen, carbon, oxygen, and nitrogen arranged in an exact and complex relationship around a central ring. At the ring__ center is a single atom of magnesium. Now: If you remove the atom of magnesium and in its place put an atom of iron, you get a molecule of hemoglobin. The iron atom combines with all the other atoms to make red blood, the streaming red dots in the goldfish__ tail.

The science of genetics is in a transition period, becoming an exact science just as the chemistry in the times of Lavoisier, who made the balance an indispensable implement in chemical research.

I took a glass retort, capable of containing eight ounces of water, and distilled fuming spirit of nitre according to the usual method. In the beginning the acid passed over red, then it became colourless, and lastly again all red: no sooner did this happen, then I took away the receiver; and tied to the mouth of the retort a bladder emptied of air, which I had moistened in its inside with milk of lime lac calcis, (i.e. lime-water, containing more quicklime than water can dissolve) to prevent its being corroded by the acid. Then I continued the distillation, and the bladder gradually expanded. Here-upon I left every thing to cool, tied up the bladder, and took it off from the mouth of the retort._ I filled a ten-ounce glass with this air and put a small burning candle into it; when immediately the candle burnt with a large flame, of so vivid a light that it dazzled the eyes. I mixed one part of this air with three parts of air, wherein fire would not burn; and this mixture afforded air, in every respect familiar to the common sort. Since this air is absolutely necessary for the generation of fire, and makes about one-third of our common air, I shall henceforth, for shortness sake call it empyreal air, [literally fire-air] the air which is unserviceable for the fiery phenomenon, and which makes abut two-thirds of common air, I shall for the future call foul air [literally corrupted air].