reading quizzes 2
The formation of Pangaea was accompanied by the formation of which ocean?
Panthalassa
Coal swamps were most prominent in eastern North America during which of the following geologic periods?
Pennsylvanian
Which deltaic complex in North America originated as a result of the Taconic (Acadian) Orogeny?
Queenston
One scientific hypothesis about the origin of life holds that
RNA existed before DNA.
The Principle of Superposition yields which kind of ages?
Relative
Homeobox (HOX) genes:
-Are conserved throughout many organismal lineages, including those that lead from primitive organisms to humans. -Code for a protein that encourages DNA transcription at sites of specific genes. -Can be replicated or duplicated to form segments. -Enable the organization of a body plan.
Major animal taxa may have appeared during the Proterozoic-Phanerozoic transition in part because of:
-Biomineralization -HOX gene mutations -ecologic changes resulting from the reorganization of biogeochemical cycles. -increasing oxygen
Which of the following may have resulted in the origin of skeletons?
-Increasing food availability -Protection from increasing predation -Increased body size and the need for muscle attachment and support -increased oxygenation of the oceans allowing animals to grow larger
The Taconic "Alps" have been largely eroded away. What makes scientists think that they once existed?
-Intense regional metamorphism -Thick wedges of "molasse" following the intense igneous activity and metamorphism -Younger rocks thrust-faulted inland over older rocks -Extensive igneous intrusions
What evidence would you look for in order to corroborate an impact during the late Devonian?
-Microtektites -Iridium -Well-developed shock mineral assemblages
The broad increase of strontium isotopes during the Permo-Carboniferous likely resulted from:
-enhanced weathering by land plants. -orogeny.
Chordates are characterized by
-paired gill slits sometime during their lives -dorsal nerve cord. -notochord
The heat sources for the earliest Earth were
-radioactivity -meteor bombardment -accretion of matter through gravitational attraction.
The significance of ribozymes as a class of molecules is that:
-some can make copies of themselves (more RNA). -some can catalyze chemical reactions.
What is a foreland basin?
A low surface parallel to, and on the landward side, of mountain range that forms near a subduction zone.
Which of the following orogenies resulted in the formation of the Old Red Sandstonecontinent?
Acadian
Even if you found iridium associated with the late Devonian mass extinction, which of the following besides impact could account for its concentration?
Anoxia
Why are beds of volcanic ash exceptionally useful for lithocorrelation in the field?
Ashfalls are deposited very rapidly (geologically speaking).
The Taconic Orogeny involved the collision of North America and the microcontinent of:
Avalonia
Complete cycles of sea-level change (high to low and back to high again) associated with the tectonic cycle occur on approximately which durations?
Several hundred million years
Volcanic eruptions at the end of the Permian occurred in what is now which continent or region?
Siberia
Which statement best describes the concept of facies?
Similar environments exist at different times and different environments exist at the same time.
Increased erosion of continental rocks as a result of the Taconic and Acadian orogenies is indicated by the ratios of which stable isotope?
Strontium
One theory to explain the origin of life is called chemical evolution. According to this theory, which of the following events would need to occur first for life to evolve?
Synthesis of organic molecules
Why is the Burgess Shale found high in the Canadian Rockies?
The Burgess Shale has been subjected to a mountain-building episode (orogeny) over time.
The end of the Precambrian is marked by:
The proliferation of multicellular life
Sandstones and shales are types of sedimentary rocks. Sandstones are formed in environments like beaches or streams; shales can form in muddy spots like marshes or lakes. However, whether a rock is a "sandstone" or a "shale" is determined by examination of ___________
The size of its component grains or clasts
Which of these does not belong to the phylum Mollusca?
Brachiopods
Enhanced marine photosynthesis during the late Ordovician is suggested by more positive _______ isotope values.
Carbon
Some members of the Ediacaran Fauna most strongly resemble members of which of the following phyla?
Cnidarians
The eye of cephalopods and vertebrates is quite similar. Why?
Convergent evolution
The Central Dogma of cell biology states which of the following?
DNA --> mRNA --> protein
New England and the mid-Atlantic regions of what is now the United States were impacted by both the Taconic and Acadian orogenies. Based on the current position of North America, of the two directions below, in which direction would you predict the grade of metamorphism to increase?
East
Most of the periods of the geologic time scale were originally recognized and named by researchers studying which of these areas?
Europe
Which statement best characterizes Earth surface conditions as time moves from the middle Paleozoic to the late Paleozoic?
Falling sea level, higher albedo, icehouse conditions
Of the following, which would probably be the most reliable for detecting that a limestone formation is actually two separate limestone formations, separated by a paraconformity?
Fragments from the lower formation reworked into the lower beds of the formation that have been incorporated into the top formation
Arkoses eventually begin to appear and persist through time. What does this suggest?
Granitic rocks are being weathered and eroded.
During field work, lithocorrelation would be done by which of the following methods?
Walking the outcrop
Which of these would most likely precipitate a Snowball Earth scenario?
Increasing atmospheric oxygen
Glaciation definitely occurred during which of these times?
Late Ordovician
The type of ocean circulation during the early-to-middle Paleozoic Era most resembles that of which modern ocean basin?
Mediterranean
What is the primary reason to use igneous rocks for radiometric dating, rather than metamorphic rocks?
Metamorphism "resets" the radioactive clock, so it can be impossible to tell if the radiometric date refers to the original rock or to the date of metamorphism.
What is a cyclothem?
alternating stratigraphic sequences of marine and non-marine sediments
Each phylum is characterized by distinctive type of:
body plan
Molluscs and annelid worms are thought to have been derived from a common ancestor because:
both phyla have segmented representatives
The Burgess Shale lagerstatte is an example of an exceptionally well-preserved ecosystem from the ______________ period
cambrian
The first life on earth was most likely
chemosynthetic archaea
The endosymbiotic theory proposes that mitochondria in eukaryotic cells arose from:
endosymbiotic prokaryotes that metabolized oxygen.
The most likely cause of the late Ordovician extinctions is thought to have been:
glaciation and global cooling.
A possible early input of energy to the early Earth was mimicked in the setup of the Miller-Urey experiment. These included:
lightning
Brachiopods are characterized by their distinctive
lopophore (horseshoe-shaped, cilia-lined feeding structure)
Anomalocaris may have been the first known ___________ to be preserved in the fossil record
predator
The amount of time it takes for a particular substance to be replaced in a particular reservoir is called its _______________________
residence time
Increasing fecal pellet formation would have oxygenated the oceans by:
sending more organic matter to the ocean bottom rather than having it suspended in the water column.
The significance of greenstone belts is that they:
suggest that the Archaean Eon had microplate tectonics.
Scientists' very earliest efforts at geologic time scales were based on:
superposition and lithology.
In order to use a fossil species as an index fossil, one must know
the fossil's total range zone wherever it existed
Aerobic respiration produces more ATP than anaerobic respiration
true
Ediacaran fossils are incredibly unusual in their deposition because they are soft-bodied organisms that have been deposited on sandstone.
true
Most of the major phyla known today were present by the beginning or shortly after the beginning of the Phanerozoic
true
Oxygenation of the Earth caused global cooling because oxygen reacts with methane to remove this powerful greenhouse gas from the atmosphere.
true
True or false: The formation of Pangaea resulted in greater climatic extremes on the Earth.
true
Most of the water in the Earth's earliest oceans probably originated from
volcanic degassing
Perhaps the most significant feature of the Habitable Zone is that it allows which of these compounds to persist?
water
Which of the following was not present in the primitive atmosphere of the Earth?
water vapor
The remains of the Taconic Orogeny are found mainly in:
western Massachusetts and eastern New York state.