a.) made aerobic heterotrophic life possible.
b.) was prevalent in the atmosphere of Earth in early times.
c.) is not toxic to cells.
d.) allowed for the evolution of autotrophic organisms.
e.) is made by respiration.
The most dramatic mass extinctions of organisms are thought to have taken place at the end of the Permian period. What factor(s) likely contributed to these extinctions?
a.) Volcanic eruptions
b.) Glaciers
c.) Decrease in the oxygen content of the atmosphere
d.) Decrease in the amount of sunlight penetrating the atmosphere
e.) All of the above
The ratio of carbon-14 (14C) to its stable isotope, carbon-12 (12C), is relatively constant in living organisms and their environment; however, this changes once an organism dies. In a fossil less than 50,000 years old, the ratio of 14C to 12C would
a.) be higher because the 12C is not replenished after death.
b.) be lower, because the 14C is not replenished after death.
c.) not change, because the 14C is replenished after death.
d.) be equal.
e.) None of the above; the ratio cannot be determined in fossils less than 50,000 years old.
Oxygen-generating cyanobacteria liberated enough O to open the door to _______ reactions in metabolic pathways leading to the evolution of larger _______ cells.
a.) oxidative; eukaryotic
b.) reductive; prokaryotic
c.) reductive; eukaryotic
d.) reductive; archaean
e.) oxidative; prokaryotic
Which of the following about Earth’s crust is true?
a.) It does not move over time
b.) It is composed of molten lava plates
c.) It is known as the asthenosphere, or “magma”
d.) Pieces of the crust can move by continental drift
e.) Both b and d
Coal is the fossilized remains of
a.) pine trees.
b.) tree ferns and horsetails.
c.)flowering plants.
d.) grasses.
e.) ginkgos.
The half-life of carbon-14 (14C) is approximately 5,000 years. The ratio of 14C to carbon-12 (12C) in a fossil 20,000 years old would be _______ that of a living organism today.
a.) the same as
b.) 4/1
c.) 1/4
d.) 1/8
e.) 1/16
a.) are scarce because organisms were not as prevalent during the history of life on Earth as they are today.
b.) provide a glimpse into the history of biodiversity on Earth.
c.) are less numerous for marine animals than they are for terrestrial animals.
d.) are scarce because most organisms died in oxygen-poor environments.
e.) provide a complete record of biodiversity on Earth.
Which of the following would be possible to date by means of radioactive carbon?
a,) A mastodon that is about 15,000 years old
b.) Remains thought to be associated with King Tut (who lived 2,500 years ago)
c.) A Homo erectus skeleton thought be around 800,000 years old
d.) Both a and b
e.) None of the above
Which of the following periods did not end with mass extinctions?
a.) Silurian
b.) Cretaceous
c.) Triassic
d.) Permian
e.) Devonian
Which of the following eras in Earth’s history is the longest?
a.) Mesozoic
b.) Precambrian
c.) Paleozoic
d.) Cenozoic
e.) Cambrian
Which of the following provides the best evidence for continental drift?
a.) The good fit of the coastlines of western Africa and eastern South America
b.) That similar fossils of flying insects are found in places distant from each other
c.) That similar rock formations are found in Appalachia and Antarctica
d.) The mass extinctions of marine organisms
e.) All of the above

I'm Niki!

Would you like to get a custom essay? How about receiving a customized one?

Check it out