Origin of life
Origin of universe
· 13.8 billion years ago
Origin of Earth
· 4.5 billion years ago
· Solar system is forming
· Rocks and meteors are colliding
· Heavy stuff go to the center
· As earth spins it is getting denser
· Not dense enough to hold gases so no atmosphere
· Icy rock
· Inside of becomes molten
· Pressure
· Causes lots of eruptions and geysers
· Primordial atmosphere
· Volcanic gases start to form
· H20, CO2, NH3, N2, H2S
· Reduces oxygen
· So no o2
· Important because life could not have formed if there was oxygen around
· Oxygen would just break those organisms down
· Gases were escaping
· Formation of monomers
· Amino Acids, Glycerol, Monosaccharides
· From primordial gases
· Have crucial energy sources to have formed
· Intense thermal source
· Center of Earth
· Released heat from volcanoes
· Intense lightning storms
· Contrast between temperatures on the surface of Earth and the atmosphere caused this
· Intense UV radiation
· No ozone layer to block out these rays
· These energy sources and monomers combined together
· Millers apparatus tested this
· Similar gases with spark chamber, condenser, then boiling back to gas
· Formed a gooey group of organic materials
· Formation of polymers
· Monomers combined together to form polymers
· Amino acid X 2= protein
· Mono Sac X 2= Poly sac
· Glycerol + fatty acids = Lipids
· Nucleotides X 2= nucleic acids
· Used these energy sources to do so
· Intense thermal source
· Center of Earth
· Released heat from volcanoes
· Intense lightning storms
· Contrast between temperatures on the surface of Earth and the atmosphere caused this
· Intense UV radiation
· No ozone layer to block out these rays
· Formation of water
· Earth is really hot
· Causes water to evaporate quickly initially
· Causes earth to be rocky and rigid with gasses
· Earth then cools down
· Water collects on Earth surface
· Forms a “dilute soup”
· Water with consumable things in it
· 5-10% is organic
· Becomes more smooth
· Dilute soup is still forming
· Aggregation
· Molecules are in a clump
· These are called aggregates
· 2 types
· Both are Prebions
· Coacervates
· Proteins + carbon
· Microsphere
· Proteins
· Prebionts are not living
Living organism- physical entity that utilizes matter and energy from the environment to grow and reproduce
· Prebions
· System that uses energy
· Consumes other molecules to maintain themselves
· Some point they become able to divide
· RNA forms and becomes “RNA world”
· Proteins
· No DNA
· First molecules to direct protein synthesis
· Prokaryote consumers develop
· Replicated as aggregates begin to grow and split
· First Organism
· 3.5 billion years ago
· Prokaryote
· Consumer-anaerobic
· Heterotroph hypothesis
· Heterotrophs before autotrophs
· Earth is cooling
· Competition for organic molecules is increasing
· Aggregation is happening in tidal pools
· Soup is becoming more and more dilute
· Less organic material is being formed while more is being consumed
· Photosynthesis becomes useful
· Ex. “A” is useful
· Concentration of A goes down
· Organism find way to turn B->A
· B becomes useful and the concentration goes down
· So you need new things to turn into other things so you can get the final product
· Autotrophs forming
· Chemiosmosis is formed—it’s chemosynthesis
· Heat energy is made into food at the bottom of Ocean through heat vents
· Photosynthesis is formed
· Food from sun
· On surface of ocean cause light cant go that deep
· O2 is starting to be released for the first time
· This is poisonous to heterotrophs
· Not all heterotrophs die though
· Through evolution some heterotrophs get the ability to use oxygen to help break down organic material
· Oxygen revolution
· Catastrophe to living organisms
· All molecules start to break down
· Atmosphere becomes oxidizing
· DNA
· Comes in because it is more stable
· Not easily damaged
· Double helix
· First cell -> Autotroph
· Diminishes autotrophs
· First autotroph-> First Aerobe
· Autotroph
· Prokaryote, autotroph
· Anaerobic—should be aerobic
· Aerobe
· Prokaryotic autotroph or heterotroph
· Anaerobic—should be aerobic
· Endosymbiotic theory
· A theory stating that the eukaryotes evolved through a process whereby different types of free-living prokaryotes became incorporated inside larger prokaryotic cells and eventually developed into mitochondria, chloroplasts, and possibly other organelles.
· 3 important events
· Cambrian explosion
· 541 million years ago
· Big evolutionary event
· Occurs in a time frame of 20 million years
· Every existing phylum in this time can be found
· Fossil evidence
· 2 places
· Chenjiang
· China
· Burgess Shale
· Canada
· Happened because oxygen levels were increasing to modern day levels
· Provided apparatus for animals to adapt
· Mass extinction
· 252 million years ago
· 90% of all marine species go extinct
· 30% of all terrestrial species become extinct
· Lasted for 100 thousand years
· Happened because meteor hit
· Caused massive global warming
· “Dinosaur” extinction
· 60 million years ago
· Other animals became extinct too
· Happened because meteor hit
· We think this is what happened because huge crater hit the Yucatan peninsula in Mexico
· Crater has iridium
· No iridium found on earth so it had to come from space
· 11 km wide
· This big of a crater must have raised huge dust cloud that blocked the sun from hitting Earth
· Crater is 100 km
· Organism moving to land
· Came to land because of O2 enrichment
· However animals drying out becomes problem
· Breathing wastes a lot of moisture
· Internal fertilization occurs
· So no drying out
· Terrestrial eggs have hard shells
· Animals develop amnions
· Help sequester waste products
Human Classification
DOMAIN SIDE----WHAT NAME IT IS FOR HUMANS
Kingdom---Animalia
Phylum--- Chordate
Class--- Mammalia
Order--- Primates
Family---Hominidae
Genus---Homo
Species--- Sapiens