BIO Topic 8
what are the 7 proporties of life that all organisms share
cellular organization, enery and metabolism, repoductiom, heredity and evolution, growth and development, regulation and homeostatsis and response to stimuli
why are virsuses not considered organisms
no cellular organization, no internal metabolism and no grwoth or development
so if something does not have a of the 7 proporties of life they are...
not considered an organism
what is cellular organization
organisms have multipule cells
energy and metabolism
convert energy from enivronement to survive
what is reproduction
can reproduce
heredity and evolution
genetic material that can be passed down (inherited)
regulation and homeostatsis
regulate internally to stay stable despite changes
response to stimuli
respond to stimuli good for survival
what is a fossil
preserved impression of organism from past
what is stromatolite
layers of rock binded together
stromaolite can look different due to
photosynthesis
all organisms use
carbon
why is carbon good
binds to 4 different atoms, strong or weak covalante bonds, lots of diff changes, basically carbon good
what are the important organic elements
C, O, H, N
why are the organic elements important
they form biological molecules, such as carbs, proteins, fatty acids, nucleic acid
how did life originate of earth
organic molecules to protocells
what are the 4 necessary steps for life to emerge
1. make small molecule, 2. small molecules combine into macromolecules (big ones), 3. macromolecules into protocells, 4. emerge selfreplicating molecules to pass down genetic information
what are the names of the 4 steps
abiotic synthesis of organic molecules, polymerization into macromolecules, formation of protocells, origin of inheritance
what is pimordial/prebiotic soup
hypothetical group that gro from non-living(abiotic)(water, energy monomers) things into living(biotic)
what is stanley miller's experiment
"mini earth experiment" replicated the atmopheres and then added electric sparks (lightning) and how out that it could form amino acids. showed that right conditions and basic ingridients can form important life molecules
what is monomer
1 molecule
what is oligomers
2-10 repeated molecules
polymers definition
+10 molecules
what is a catalysr for polymerization of RNA
clay
life can come from
the abiotic world
what are the conditions needed for polymerization
precursor molecules (simple molecules/building blocks), heat enery (thermal), catalyst (Fe,Pb,Mg)
what is polymerization
small molecules(monomers join together to form big ones (polymer)
what is a protocell
droplets with memebranes, not living since lack genetic material but have other proporties of living organisms. can keep inside conditions stable from outside
experiments of protocells show that
they can reporduce, have internal metabolism, growth, regulate and have a response to environement.
protocells since they dont have genetic material they cannot
pass traits or evolve
proteins (like enzymes) made using DNA/RNA but
DNA/RNA need enzymes to be made
what is the RNA hypothesis
life might have started in an RNA word where RNA was the main molecule, handlying genetics and catalysts before DNA and proteins evolved
RNA can act as both
geneti cmaterial and catalysts
ribozymes (special RNA molecules) can
copy RNA molecules (self-replication)
what are ribosymes
RNA molecules that are catalysts and can function as enzymes
why is RNA replication good for natural selection
there can be errors in the replication which leads to varation, since deifferent sequences can be better than others
passing RNA of splitting vesicule to daughter vesicles contitue
inheritance
how to fossils help us understand the history of life
extinct species, similarities to modern organisms rapid changes in morphology
whats Biostartigraphy
a way to find the age of fossils not always accurate, used for sedimentary rocks
what is radiomatric dating
a way to determine the exact age of rock or fossils. precise, used with magmatic rocks
Faunal succession meaning
pattern of rock layers that have specific fossils in them in a vertical sequence. help find age of differnet layers
whats a biozone
sections of rock layers that have specifid types of fossils. helps date the layer
what is a biomarker
a species that have short life spans are helpful in dasting rocks
why are biomarkers good at helping us date rocks
they have specific habitats, widely spread out geologially, different morphologically and well preserved
Biostratigraphy uses what technique
biomarkers
what does radiometric dating do
measures the changes in isotopes inside fossils or magnetic rocks but not sedimentary rocks
how does radiometric dating work
when are oganisms dies it stops making carbon, C14 decays into N14 but C12 stays the same. so you can compare the two to find out how long its been since the organism has died
whats an isotope
an element with the same number of protons but different number of neutrons
what is half-life
time it takes for half of the C14 to decay into N14
many fossil have been
distroyed over time or havent been discovered
more likely to have species with hard shells
because they are more likely to fossilize
Discontinuities are
gaps in the fossil record
what are some of the causes of an incomplete fossil record
geological events, ecological events and evolutionary events
what is a geological event
plate mouvements, erosion or changes in how sediment builds up
what are ecological changes
habitat loss, change in climate
evolutionary events are
new species evolving, moving new areas or going extinct
the cambrian explosion occured
535-525My
the cambrian explision increased
morphological diversity
bilateral symmetry means
an organisms body can split into two equal halves that mirror eachother
what evolutions caused by the cambrian explosion, do to bilateral symmetry
development anterior sesning organs, anterior predation appendages, and posterior appendages for movement
what are anterior sensing organs
the develoopment of a nervous system
what is anterior predation appendages
prey capturing and feeding
what does posterior appendages for movement mean
swimming crawling flying, etc..
cambrian explosion caused many adaptive radiations which means
a group of organisms evolves into lots of new species with different traits that help them survive
what can cause mass extinction
change in temperature, volcanic eruptions, meteorites, etc
what will always follow a mass extinction
new adaptive radiations and new families
what are key innovations in the fossil record
first cell (prokaryotes), increases in atmospheric O2 concentration, endosymbiosos(eukaryotes), sexual reproduction, multicellularity and colonization of land
all living organisms
synthesize and use only L optical isomers of amino acids
the genetic code from LUCA is
almost universal
what are the three domains in the the tree of life
eukarya, archea and bacteria
in eukarya evolved from
prokaryotes
Eukarya cells perform serial endosymbiosis which is when
it swallows another cell and instead of digesting it, it keeps it and gains its abilities. (kirby)
serial endosymbiosis originiated what cells
mitochondria and plastids
plastids do what
enables photosynthesis
what does mitochondria does what
aerobis respirations (using oxygen to make energy)
what is the colonial hypothesis
single-celled organisms living in the same colony, stick together without dividing and eventually they do certain jobs and work as a team.
what is the symbiosis hypothesis
differnet kinds of species cells comes together closely to help eachother and form a long term reltionship where they both benefit. but is unlikely because they would both need to combine DNA