“Life is old. The dinosaurs are perhaps the most famous extinct creatures, and they had their beginnings 250 million years ago. But life dates back much further.” In August 2016 fossilised microbes were found dating back 3.7 billion years ago. Earth is 4.5 billion years old. This means life formed in the billion years between “Earth coming into being and the preservation of the oldest known fossils.”
Cells make up all living things and were first discovered in the 17th century. The most numerous of living things are microorganisms made up entirely of single cells. “The big biological breakthrough of the 19th Century was the theory of evolution, as developed by Charles Darwin and others.” Darwins theory sets out how the vast diversity of life could be traced back to a single common ancestor.
In 1952 Miller reproduced amino acids from simple chemicals. Amino acids form proteins that “control most biochemical processes in our bodies.””Today we take it for granted that DNA carries our genes, but this actually came as a shock to 1950s biologists. Proteins are more complex, so scientists thought they were the genes.” DNA tells your body how to make proteins. Each protein is a long chain of amino acids. RNA is the middle man. “DNA makes RNA makes Protein”
“The ability to create offspring is absolutely central: the only way an organism can “win” is to leave behind lots of children.”
Power from Protons
Green plants extract energy from sunlight. Energy builds cells. the process “of harnessing energy is so utterly essential, many researchers believe it must have been the first thing life ever did.” “Wächtershäuser imagined a flow of hot water streaming out of a volcano. The water was rich in volcanic gases like ammonia, and held traces of minerals from the volcano’s heart.”
Rocks, minerals and chemical reactions help organic compounds fuse into larger ones. “All the other things that make up modern organisms – like DNA, cells and brains – came later.”
Volcanic ridges exist underwater and in hot springs, chemical rich water pumps out through holes in the rocks. today they are thick with bacteria and life. Could this be where life started? It would have to be alkaline water due to the way cells store proton energy from the sun. The middle of the Atlantic Ocean ridge is alkaline and carbonate minerals have clumped together. This is important as carbon forms the basis of all life and forms covalent bonds with several other atoms such as hydrogen, oxygen, nitrogen, and sometimes sulphur and phosphorus. All found in the human body.
“They now knew that the rocks of alkaline vents were porous: they were pocked with tiny holes filled with water. These little pockets, they suggested, acted as “cells”. Each pocket contained essential chemicals, including minerals like pyrite. Combined with the natural proton gradient from the vent, they were the ideal place for metabolism to begin.”
“Once life had harnessed the chemical energy of the vent water, Russell and Martin say, it started making molecules like RNA. Eventually it created its own membrane and became a true cell, and escaped from the porous rock into the open water.”
Cells are made up of a plasma membrane, nucleus which holds the DNA and acts as the command centre, cytoplasm that holds RNA and holds the ribosome (molecule that reads the RNA and strings together amino acids to make proteins) and the cytoskeleton. Enzymes are proteins inside cells and speed up the chemical reactions.
Enzymes in nature often have a metal atom at their core this points towards the location of volcanic ponds or springs, these also have more ultraviolet radiation from the sun. It might be here that life started.
“Almost 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium. All 11 are necessary for life.” https://en.wikipedia.org/wiki/Composition_of_the_human_body
Carbon based life
“The sixth element on the periodic table supports life as we know it
Many scientists describe life as we know it as ‘carbon-based’. Fundamentally, without carbon, life on Earth would not be possible.
Carbon is a relatively small atom: its nucleus contains six neutrons and six protons. It has a full inner shell (two electrons) and four electrons in its outer shell. Having four electrons means it can form many different types of bonds.
Carbon also forms covalent bonds with several other atoms, such as hydrogen, oxygen, nitrogen, and sometimes sulfur and phosphorus. Carbon readily forms single, double or triple bonds, chains, branched chains and even rings. It can bond with itself, as well, to form strong substances like diamond and graphite.
This versatility and ability to form many bonds enables carbon to form the many different shapes adopted by the complex organic compounds that make up the bodies of animals and plants. Some of the carbon chains needed for life are millions of atoms long.”