Evolution of Prokaryotes, Eukaryotes, and Viruses

• Prokaryotes contain circular DNA while Eukaryotes contain linear DNA.
• Prokaryotes are found in Archaea and Bacteria, while Eukaryotes are found in Animalia, Plantae, Fungi, and Protista.
• Miller’s Experiment demonstrates the spontaneous formation of organic molecules and creates H2, CH4, NH3, and some amino acids.
• The first polymer formed in Miller’s Experiment was the RNA molecule as it is capable to self-replicate and be a catalyst itself.
• A cell was formed when lipids were able to enclose the RNA by chance.
• The evolution of metabolism has a strong relationship with atmospheric conditions.
• Glycolysis occurred first since the atmosphere has small concentration of oxygen and this pathway does not require oxygen.
• Photosynthesis became possible when oxygen level increased and is more adaptive since it can also do glycolysis and hence producing more energy.
• Eukaryotes are believed to have arose from archaea due to the similarity in metabolism and genes.
• invagination hypothesis explains the compartmentalization of cellular components as it provides additional nuclear membrane internally.
• Unicellular plants transition to multicellular when there’s no food.
• A mechanism for multicellularity is the production of spores where it allows dispersion in order to colonize an area where food is available.
• Reductive evolution is a more conducive theory explaining the origin of viruses.
• 5-8% of human DNA is made up of retrovirus and this is the reason why we acquire HIV (once activated).
• Without cell nucleus since it has no compartmentalization

  prokaryotes
• Circular DNA

  prokaryotes
• Archaea and Bacteria

  prokaryotes
• Contains nucleus and other organelles

  eukaryotes
• Linear DNA

  eukaryotes
• Animalia, Plantae, Fungi, Protista

  eukaryotes
• amphiphatic due to hydrophobic tail and hydrophilic head

  lipid membrane
• hydrophilic head composed of phosphate group responsible for its polarity
• hydrophobic tail composed of hydrocarbon chain
• glycolysis occurred first since the atmosphere has small concentration of oxygen and this pathway does not require oxygen
• Photosynthesis became possible when oxygen level increased; more adaptive since it can also do glycolysis and hence producing more energy
• Oxidative metabolism became more adaptive as well and it can produce greater power
• prokaryotes have removed unnecessary structures and became obligate intracellular parasites

  reductive evolution