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@ In 2007, Kahr studied the ability of crystals to transfer genetic information, using crystals of potassium hydrogen phosphate.
@ He cleaved imperfect crystals & used them as seeds to grow new crystals in a solution.
@ He then examined the new crystals & found that the imperfect properties of the first crystals were transferred to the new crystals.
@ However the new crystals were unable to store or transfer these properties to the next generation.
@ RNA world hypothesis: RNA can self replicate & catalyze molecule formation without DNA or proteins.
@ RNA provides a copying template to join RNA pieces together & makes self-replication.
@ James Ferris showed that clay minerals could form RNA in water solution. Then RNA joins nucleotides together to form longer chains.
@ RNA was found to be able to express and maintain the genetic information in organisms
@ Lincoln and Joyce identified an RNA enzyme that catalyzes self replication. Hence RNA can reproduce molecules.
@ Iron-sulfur world hypothesis: Christian de Duve showed that the enzymes carbon monoxide dehydrogenase & acetyl-CoA synthase catalyze the formation of acetyl- CoA clusters from iron and sulfur reactions.
@ This proved that acetyl-CoA can organize molecules on a metal sulfide surface.
ORIGIN OF LIFE: SUMMARY
@ Charles Darwin (Warm Pond Theory) contains ammonia & phosphoric salts, light, heat, & electricity. From all that a protein was formed & changed to living things.
@ Alexander Oparin (Primordial soup theory) contains organic molecules created by action of sunlight in water. Organic molecules combined to form to give living cells.
@ Miller-Urey experiment (Biopoesis Theory) in mixture of water, hydrogen, methane, & ammonia, all cycled in an electric field. Carbon changed to protein.
@ Sidney Fox (combined Biogenesis & Soup Theories) allowing aminoacids to dry out. He noticed aminoacids forming long, thread-like molecules (Proteinoids).
@ Then Fox baked volcano lava over aminoacids, put in water, to form proteinoids, and proteinoids combined to form the spheres Protobionts (one-cell creature)
@ Graham Cairns Smith (Clay hypothesis) Organic molecules arose on inorganic silicate crystals solution.
@ Kahr proved the ability of crystals to transfer genetic information using potassium hydrogen phosphate
@ James Ferris (RNA World Hypothesis) Clay form RNA in water & RNA joins nucleotides to form longer chains
@ Lincoln & Joyce identified the RNA enzyme helping RNA produce molecule.
@ Christian de Duve (Iron-Sulfur World Hypothesis) The acetyl-CoA can organize molecules from iron- sulfur clusters.
Microbial Evolution
@ The oldest living creatures found in rocks and inorganic minerals are about 3.5 billion years old, one billion years after Earth formation.
@ The evolution of microorganisms are studied from the remains of the past (fossils).
@ Fossils may be observed in its solid state or from its prints on rocks
@ Blue-green bacteria were the first organisms discovered in history, detected in a form of stromatolites (bacterial colonies with minerals)
@In 1936 Cluyver & Niel stated that the first
bacterium discovered was spherical in shape.
@ Barghoorn & his associates examined 3.5 billion year old rocks & discovered many organisms: single, paired, long, thin, flat, wrinkled, or folded.
@ First organisms discovered were anaerobic, since oxygen was absent at that time.
@ In 1965 Schopf & his co-workers discovered preserved rod-shaped & spherical organisms about 2 billion years old.
@In 1977 Woese & co-workers described the
methanogenes (methane-producing) bacteria .
It has a different RNA & genetic composition
@ In 1977 Fox and Woese divided prokaryotes into two: Bacteria & Archaebacteria.
@ The archaebacteria include three kinds: * Methanogenes * Extreme halophiles, * Thermoacidophiles.
@ The methanogenes were found to live at a temp. 65°-70eC, anaerobic, & utilize carbon dioxide & hydrogen & give off methane gas
@Extreme halophiles grow in salty in oceans .
They have a photosynthetic mechanism from
pigments inside the organism .
@ Thermoacidophiles grow in hot, acidic places above 90°C. They have different cell wall, cell membrane, & ribosomes.
@ Mitochondria & chloroplasts structures are thought to descend from prokaryotes.
@ The mitochondrion is thought to have been a bacterium & the chloroplast to have been a structure of the blue-green bacteria.