BIO 19 (3)

a single species that has evolved into several different forms that live in different ways has undergone

adaptive radiation

the mesozoic era occured

after the paleozoic era

which of the following was not characteristic of earth before the oceans formed?

an atmosphere containing oxygen gas

what prevents organic molecules from forming on thier own and remaining intact today?

atmospheric oxygen is too reactive

the first organisms on earth were most like todays

bacteria

in the past, mass extinction encouraged the rapid evoultion of surviving species

by making new habitats available to them

earths most recent era is the

cenozoic

the process by which 2 species, for example, a flower and a pollinating insect, evolve in response to changes in each other over time is called

coevolution

the endosymbiotic theory proposes that eukaryotic cells arose from

communities formed by prokaryotes

early in earths history, while the planet was in a melted state, the most dense elements formed earths

core

during the jurassic and cretaceous periods, the dominant land animals were

dinosaurs

a fossilized dinosaur, found with fossils of the flowering plants tht it ate, must have lived

during the mesozoic era

which of these labels for fossils in a museum display contains an error?

early mammal (middle paleozioc)

example of fossils include preserved

eggs, footprints, and body parts

after precambrian time, the basic divisions of the geological time scale, from larger to smaller are

eras and periods

during the mesozioc era, animals began to invade the land

false

scientists use geologic dating to determine the absolute age of a rock in years

false

the cenozioc era included the cretaccous, jurassic, and triassic period

false

the vast majority of earths history - about 88% - is taken up by the cenozoic era

false

the leght of time required for half of the radioactive atoms in a sample to decay is its

half - life

to compare the relative ages of fossils, scientists sometimes use an easily recognized species calles an

index fossil

in addition to hydrogen, the gases used in miller and ureys experiment were

methane and ammonia

the fossil record shows that

modern organisms have unicellular ancestors, fossils occur in a particular order, most organisms that ever lived on earth are now extinct

what proportion of all species that have ever lived has become extinct?

more than 99%

a very large mass extinction in which amphibians and trilobites disappeared ocurred at teh end of the

paleozoic era

fossilized evidence of earths first forms of life would consist of

prokaryotes from the precambrian

the cambrian explsion resulted in the evolution of the first

representatives of most animal phyla

when oxygen was first released in the early seas, it combined with iron to form

rust

most fossils form in

sedimentary rock

to be useful as an index fossil, a species must have existed for a

short period over a wide geographical range

sedimentary rock is formed from

small particles of sand, silt, and clay

what was the response of the various groups of early organisms that existed when oxygen levels rose in the atmosphere?

some life forms became extinct, son survived only lin a few airless habitats, some evouved metabolic pathways that used oxygen for respiration

what does fossil evidence indicate about the order in which these 3 vertebrates evolved: bony fish with a jaw, a jawless fish, and a fish with leglike fins?

the fish with leglike fins was the last to evolve

one necessary condition for the evolution of the first life on earth was

the presence of liquid water

the galapagos finches underwent adaptive radiation, a process in which a small group evolves into several different forms that live in different ways

true

how would you date a sample of rock that yo ususpect as being one of the earliest on earth?

use a radioactive isotope with a long half - life

why did oceans not exist on earth nearly 4 billion years ago?

water remained a gas because earth way very hot

miller and ureys experiments attempted to demonstrate

whether organic molecules could have formed before life was present