Chapter 15 Tracing Evolutionary History Flashcards
Earth is how old?
4.6 Billion years old
How long ago did prokaryotes evolve?
3.5 billion years ago
single celled ______ are considered to have evolved 2.1 billion years ago.
eukaryotes
stomatolites
fossilized mats containing photosynthetic bacteria
oxygen revolution
2.5 billion year old fossilized prokaryote mats suggest that photosynthetic bacteria produced O2 which created an aerobic atmosphere important for life is referred as _________.
Earth’s early atmosphere contained
H2O, CO, CO2, N2, and CH4
biogenesis
all organisms today arise via ________ stating that life comes from life.
Biogenesis Paradox
the discrepancy of how the 1st living organisms got here if life comes from life.
Chemical evolution in 3 stages
collection of monomers, formation of RNA polymers (simple genes), assembly of complementary RNA (replication)
Stanley Miller
simulated what he thought was the “early Earth” in his lab
Macro-molecules we likely synthesized from simpler molecules using
energy
simple organic molecules can polymerize on
hot rocks or clay
Short _____ pieces may have been acted as the 1st type of nucleic acid present on the early Earth.
RNA
If a RNA polymer formed the catalytic ability of RNA may have lead to
self replication of RNA
Ribozymes
RNA molecules that act like enzymes
because _________ have a hydrophobic tail and hydrophillic head, if they are placed into an aqueous solution they form a ___________
phospholipids, self sealing sphere
natural selection
favors those co-ops that are most efficient and effectively reproduced or divided.
Distinct Geological eras are used to categorize organisms into time frames when they evolved and existed on Earth.
most recent at top
Cenozic
Mesozoic
Paleozoic
Radiometric dating uses _________________ which decay with a predictable half-life
radioactive isotopes
Pangea
super continent
Plate tectonics theory
the Earth’s crust is divided into giant irregularly shaped plates that float on the underlying mantle.
Continental drift
suggest that lungfish evolved when Pangaea was still intact because fossils of lungfish have been found everywhere except Antarctica.
Fossil records show that the vast majority of species that have ever lived
are now extinct
In the last 500 million years ______ mass extinctions have occured causing more than ______% of the species to become extinct.
5, 50
