Microbial Evolution and Ecology Flashcards
how old is Earth
4.5 - 4.6 billion years old
abiotic synthesis
biological molecules from inorganic precursors
Stanley Miller
1953
abiotic synthesis research using what we think the conditions were for early Earth
deepsea hydrothermal vents
best idea currently for what atmosphere was like
panspermia
seeding from space
ribozymes
RNA that copies itself/other strands
RNA World
early cells used RNA instead of DNA
life needs containment, which is theorized to be via
liposomes
liposomes are made from
phospholipids
prokaryotes came around
3.8 - 3.5 billion years ago
stromatolites
sedimentary rock formations
can have evidence of early prokaryotic cells
which is the likely first major metabolic pathway to evolve
glycolysis, it is universal across all life
photosynthesis
earliest forms did not use water or release oxygen
when did oxygenic photosynthesis occur? from who?
2.7 billion years ago
cyanobacteria
The Great Oxygenation Event
2 billion years ago
made oxygen prevalent in atmosphere
eukaryotes evolved
about 2 billion years ago, after oxygenation
how did eukaryotes evolve
endosymbiosis
eukaryotes and archaea share a common ancestor
lokiarcheota
lokiarcheota
oldest archaea
discovered in 2015
multicellular organisms
evolved 1.5 billion years ago
unicellular cells specialized
more advantages
slower rate of growth
natural selection
descent with modification
artificial selection
humans guiding evolution by selecting traits
example of selection in bacteria
drug resistance
vancomycin
antibiotic that targets normal cell wall
ecology
study of relationships of organisms to each other and to their environment
biotic interactions
between organisms