Chapter 23 And 26 Flashcards
When molten rock cooled it formed what? And what arose?
Chemically rich oceans formed by water condensation; life
Earth was formed as a hot mass of molten rock about ______?
4.5 bya
Why are the 7 characteristic of all living things?
- Composed of cells
- Complex and ordered
- Respond to their environment
- Can grow, develop, and reproduce
- Obtain and use energy
- Maintain internal balance
- Allow for evolutionary adaptation
Panspermia
The idea that life may have effected earth from some other planet or mars
First organisms emerged
3.8-2.5 bya and lived in very high temperatures
Because of no oxidation, meaning lack of ______, there ample availability of ____ ____ and their _____.
Oxygen; hydrogen atoms; electrons
Popular view of early earth atmosphere is
Carbon Dioxide (CO2) Nitrogen Gas Water Vapor Hydrogen gas Other sulfur, nitrogen, and carbon compounds Atmosphere lack oxygen gas (o2)
Miller and Urey experiment
Assembled a reducing atmosphere rich in hydrogen and no oxygen. Temp near 100C
Not a question: facts:
Miller Urey experiment found that methane gas (ch4) converted to simple carbon
Later experiments produced more than 30 carbon compounds including amino acids (adenine also produced part of DNA )
First genetic molecules
RNA; work with ribosomes to link amino acids during protein synthesis
Primitive organisms may have been ______, but built what they need from compounds using ——— or ————
Autotrophic; photosynthesis; chemosynthesis
CO2 levels decreased because?
Weathering of rocks; co2 and h2o formed carbonic acid, the acid reacted with rocks that had calcium carbonate (caCo3) releasing ions (hco3-) and ca+ and moved through rivers and reverted to precipitate caco3 , decreasing co2 and lower earth temp
Stromatolites
Mats of Cyanobacteria cells that trap mineral deposits
The 200my lag between the origin of photo synthesis and substantial levels of o2 explantation is
O2 reacted with iron to form iron oxide in oceans
O2 reacted with uv to create? And is critical?
O3 (ozone) and it reduces the mutation rate caused by uv light
What is the first explanation to do plants contribute to glaciations
1) colonization of plants (~490 MYA)
•release organic acid which increased weathering , releasing phosphorus, that enters oceans increasing algal photosynthesis, co2 removed from atmosphere to form algal tissue the reduced levels of co2 result in temp decrease and glaciation
••
What is the second explanation to do plants contribute to glaciations
2) Vascular plant diversification concurrent with 2nd glaciation
• extensive root system increased rock weathering and released nutrients that triggers algal growth in ocean
Hadean
Oldest rocks, 4600-4000 mya
Archean
Oldest fossils of prokaryotes, 4000 mya - 2500 mya
Proterozoic
2000mya - Cyanobacteria and oxygen in atmosphere
1600mya- oldest definite fossils of eukaryotes
2500-540 mya
Phanerozoic
600mya - Cambrian explosion and increase in diversity
450- increase in land plants
100- first flowering plants, birds, marsupial mammals
Rock fossils are created when
Organism is buried in sediment
Calcium in bone or other hard tissue mineralizes
Surrounding sediment hardens to form rock
Biomarkers
Their high c12 content suggest a biological origin
Aging Fossils are measured by Relative age
Position of fossil in sediment
Aging Fossil are measure by absolute age
Age if fossil is estimate by rates of radioactive decay chemical element isotopes mainly krypton an argon
Isotopes half life is
The rate of decay, the amount of time needed for one half of the orginal amount to be transformed
Rodinia
All continents
Gondwana
All current south hemisphere continents
Pangea
Formed from Gondwana
Three monophyletic domains or classes are
Eubacteria, archea, eukaryote
Eukaryotes domain has 6 supergroups called
Chromalveolates Rhizaria Archaeplastida Excavates Amoebozoa Opisthokonta
Bacteria and archae are distinct from eukaryotes because
They lack compartmentalization
What has and extensive endomembrane system?
Eukaryotes
Golgi apparatus and endoplasmic reticulum facilitates ?
Intercellular transport
Mitochondria and Chloropasts entered early eukaryotic cells by endosymbiosis
Mitochondria descendants of purple sulfur and chloroplasts derived from Cyanobacteria bacteria
In endosymbiosis, algae acquired chloroplast twice
1) red and green algae common ancestor an eukaryotic cell engulf cyanobacteria
2) brown algae engulf red algae
Multicellurity allowed organisms to deal with
Differentiation
Meiosis is associated with
Crossing over
Rapid diversity occurred in
Cambrian
Evolutionary innovations occurred when life was primarily
Aquatic
Eukaryotes characteristics
Compartmentalization:additional levels of transcription and translations
Multicellular: differential of cells into tissues
Sexual reproduction: greater genetic diversity
Taxonomy
Science of classifying living things
The genus name is
Capitalized and in italics
Hierarchical taxonomy
Domain Kingdom Phylum Class Order Family Genus Species
Evolutionary relationships among organisms accomplishs:
An orderly logical way to name organisms
Insight to understand history and major features and functions
Systematics
Reconstruction an study of evolutionary relationships
Phylogeny
Hypothesis about patterns of relationship among species
All organisms share many characteristics .. 4 are?
Have one or more cells
Carry out metabolism
Transfer energy with ATP
Encode hereditary info in DNA
Derived characteristic
Similarity that is inherited from the most recent common ancestor of an entire group
Ancestral characteristics
Similarity that arose prior to the common answer or of the group
Synapomorphies
Shared derived characters are considered informative about evolutionary relationships
Clades
Species that agar a common ancestor and indicated by the possession of shared derived characters
Homoplasy
A shared character state that has not been inherited from a common ancestor
Convergent evolution
Whales and penguins have flipper for limbs but no common ancestor
Evolutionary reversal
Snakes and lampreys do not haves limbs no common ancestor
Principle of parsimony
Which favors the hypothesis the requires fewest assumption to answer the question
Monophyletic
Includes the most recent ancestor of all the group and all decedents (Clade)
Paraphyletic
Includes most recent common ancestor of group but not all decedents
Polyphyletic
Does not include most recent common ancestor of all members of the group
Biological species concept
Defines species as groups of interbreeding populations that are reproductively isolated
Phylogenetic species concept
Species in a population or set of populations characterized by one or more shared derived characters
Phylogenetic species concept solves two biological species concepts problems
1) biological species concept cannot be applied to allopatric species (= not overlapping species)
2) psc looks to the past to see if species separated long enough to develop their own derived characters
Homologous
Derive from same ancestral source; dolphin flippers and frog legs are modifications limb
Homoplastic structures
Do no derive from ancestral sources; wings of birds (modification of limb) and dragonfly wings (modification of gill like appendages)
Difference between HIV 1-2
Hiv1 Spreads quickly and hiv2 less transmitted , longer period before initial infection and illness, weaken the immune system at much lower rate
