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White and colleagues — including her graduate advisor, retired JPL scientist Michael Russell — simulated vents that didn't spew particularly hot water (it was only about 212 FahrenheitThe Fahrenheit scale is a temperature scale, named after the German physicist Daniel Gabriel Fahrenheit and based on one he proposed in 1724. In the Fahrenheit temperature scale, the freezing point of water freezes is 32 °F and water boils at 212 °F, a 180 °F separation, as defined at sea level and standard atmospheric pressure. " data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">Fahrenheit, or 100 degrees CelsiusThe Celsius scale, also known as the centigrade scale, is a temperature scale named after the Swedish astronomer Anders Celsius. In the Celsius scale, 0 °C is the freezing point of water and 100 °C is the boiling point of water at 1 atm pressure." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"Celsius). One major challenge with creating the experimental setup was maintaining the same pressure found 0.6 miles (1 kilometer) below the ocean surface — about 100 times the air pressure at sea level. Previous experiments have tested similar chemical reactions in individual high-pressure chambers, but White and her colleagues wanted to more fully replicate the physical properties of these environments, including the way the fluids flow and mix together. This would require maintaining the high pressure in multiple chambers, which added to the complexity of the project. (Because a crack or leak in even a single high-pressure chamber poses the threat of an explosion, it's a standard operating procedure in such cases to install a blast shield between the apparatus and the scientists.)/p>

The scientists wanted to determine whether such ancient conditions could have produced organic molecules — those containing carbon atoms in loops or chains, as well as with other atoms, most commonlyhydrogen. Examples of complex organic molecules include amino acids<div class="cell text-container large-6 small-order-0 large-order-1"><div class="text-wrapper"><br />Amino acids are a set of organic compounds used to build proteins. There are about 500 naturally occurring known amino acids, though only 20 appear in the genetic code. Proteins consist of one or more chains of amino acids called polypeptides. The sequence of the amino acid chain causes the polypeptide to fold into a shape that is biologically active. The amino acid sequences of proteins are encoded in the genes. Nine proteinogenic amino acids are called "essential" for humans because they cannot be produced from other compounds by the human body and so must be taken in as food.<br /></div></div>" data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">amino acids, which can eventually form DNADNA, or deoxyribonucleic acid, is a molecule composed of two long strands of nucleotides that coil around each other to form a double helix. It is the hereditary material in humans and almost all other organisms that carries genetic instructions for development, functioning, growth, and reproduction. Nearly every cell in a person's body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA)." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">DNA and RNARibonucleic acid (RNA) is a polymeric molecule similar to DNA that is essential in various biological roles in coding, decoding, regulation and expression of genes. Both are nucleic acids, but unlike DNA, RNA is single-stranded. An RNA strand has a backbone made of alternating sugar (ribose) and phosphate groups. Attached to each sugar is one of four bases—adenine (A), uracil (U), cytosine (C), or guanine (G). Different types of RNA exist in the cell: messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA)." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"RNA./p>

But just as eggs, flour, butter, and sugar aren't the same thing as a cake, the presence of both carbon and hydrogen in the early oceans doesn't guarantee the formation of organic molecules. While a carbon and a hydrogen atomAn atom is the smallest component of an element. It is made up of protons and neutrons within the nucleus, and electrons circling the nucleus." data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]"atom might reasonably bump into each other in this prehistoric ocean, they wouldn't automatically join to form an organic compound. That process requires energy, and just like a ball won't roll up a hill by itself, carbon and hydrogen won't bind together without an energetic push./p>