WorksheetsProbability of Life Elsewhere Exam Review
Total questions: 57
Worksheet time: 33mins
Earth's atmosphere has undergone significant changes over the past 4.6 billion years. In its earliest stages, what was the main source of gases that formed Earth's first atmosphere?
Photosynthesis
Volcanic activity
Ocean evaporation
Human activity
Which of the following gases was NOT released from volcanic eruptions to form Earth's early atmosphere?
CO2
H2O
O2
N2
Over time, the composition of Earth's atmosphere continued to evolve. One way in which Earth's atmosphere changed after its initial formation is:
Oxygen levels increased due to photosynthesis.
The atmosphere became mostly hydrogen and helium.
Carbon dioxide levels dropped to zero.
Nitrogen was completely removed from the atmosphere.
What does the geologic time scale primarily help scientists understand?
the order of events in Earth’s history based on rock/fossil evidence
the exact age of Earth in years based on rock/fossil evidence
the rate of Earth’s rotation over time based on rock/fossil evidence
the migration patterns of modern animals based on rock/fossil evidence
Which statement best explains why environmental changes caused by humans do not affect all species the same way?
A. All species have the same ability to migrate to new locations.
B. Species vary in their ability to adapt to new or altered environments.
C. Some species are more visible, so they are better protected.
D. Species that rely on specialized habitats are usually less affected.
Which gases were most abundant in Earth’s atmosphere shortly after volcanic activity began forming it?
oxygen and helium
ozone and nitrogen oxide
carbon dioxide and water vapor
nitrogen and oxygen
How did cyanobacteria contribute to major atmospheric changes on Earth over time?
They created volcanic eruptions that cooled the planet.
They removed oxygen and released carbon monoxide.
They captured carbon dioxide and released oxygen through photosynthesis.
They added methane to the atmosphere, making it denser.
How did feedbacks between Earth’s biosphere and geosphere contribute to atmospheric change over time?
Volcanoes reacted with oxygen to create nitrogen-rich clouds.
The biosphere prevented changes in atmospheric composition.
Early life changed the atmosphere, which then influenced geologic and biological evolution.
Life on Earth remained separate from geologic systems.
Which atmospheric change best demonstrates the impact of cyanobacteria over geologic time?
the increase in helium due to surface heating
the decrease in nitrogen and methane concentrations
the increase in atmospheric oxygen and the drop in carbon dioxide
the decrease in water vapor caused by ocean evaporation
What contributed to the formation of Earth's early atmosphere?
Photosynthesis
Volcanic eruptions
Meteor impacts
Plant growth
Volcanic eruptions contributed to the formation of Earth's early atmosphere and eventually the oceans by:
releasing gases such as water vapor, carbon dioxide, and nitrogen into the air
removing all gases from the Earth's surface
creating only solid rocks without releasing any gases
absorbing water from the atmosphere and oceans
What is one limitation of using rock strata and fossils to date events in Earth’s history?
They only form near water.
They provide relative, not absolute, dates for events.
They only exist in igneous rocks.
They cannot be found on all continents.
How did water vapor released by volcanoes contribute to the formation of Earth’s hydrosphere?
It formed underground lakes through earthquakes.
It reacted with carbon dioxide to make oceans instantly.
It escaped into space and left Earth dry.
It condensed and fell as rain, forming oceans.
What role did volcanic activity play in shaping Earth?
It absorbed carbon dioxide and cooled the Earth rapidly.
It produced only ash, which blocked all sunlight and prevented life.
It released oxygen and nitrogen, allowing plants to grow immediately.
It released gases that helped form the atmosphere and oceans.
What is an example of a feedback loop between Earth systems that led to long-term changes in both the environment and life?
Clouds forming caused the extinction of early organisms.
Meteors created earthquakes that led to instant biological evolution.
Photosynthesis raised oxygen levels, changing oceans and supporting new life.
Volcanic eruptions removed oxygen from the atmosphere.
Which statement best explains how volcanic activity influenced the formation of Earth's oceans and contributed to the rise of complex life?
Volcanic eruptions released gases like water vapor that condensed into oceans, forming the basis for future biological activity.
Volcanic gases like carbon dioxide and nitrogen instantly cooled the planet and supported immediate life development.
The ash from volcanoes blocked sunlight, causing long extinction periods before life evolved.
Volcanism produced only lava and had little impact on early Earth's atmosphere or oceans.
Based on the figures, which argument best supports the idea that the hydrosphere and biosphere coevolved through feedbacks over time?
Volcanoes removed gases from the oceans, reducing life's influence on the planet.
Oceans formed from comets rather than Earth processes and were unrelated to atmospheric change.
Cyanobacteria prevented feedback by isolating carbon dioxide and stopping oxygen formation.
Water vapor released by volcanoes helped form oceans, which supported photosynthetic life that changed the atmosphere.
Why does the cosmic microwave background support the Big Bang theory?
It comes only from stars in nearby galaxies
It shows galaxies moving toward Earth
It was created by supernova explosions
It is leftover radiation from a hot, early universe
The ongoing process where Earth's systems and life on Earth influence and change each other over time is called:
Biological adaptation
Ecological succession
Planetary evolution
Coevolution
What is the primary reason we see more craters on Mars and the Moon compared to Earth?
Earth has more water and surface processes that erase craters.
Mars and the Moon are closer to the Sun.
Earth's atmosphere prevents asteroid collisions.
Mars and the Moon have stronger gravitational forces.
Which natural destructive process contributes to fewer craters on Earth?
Volcanic eruptions
Erosion by water and wind
Earthquakes
Solar radiation
What evidence supports the claim that life and Earth’s systems coevolved over 3.5 billion years?
Changes in oxygen levels and fossil records
The redshift in galaxy spectra
The ratio of hydrogen and helium in the universe
The presence of craters on Earth
What is the significance of the redshift observed in galaxy spectra?
It explains the formation of craters on Mars.
It indicates galaxies are moving closer to Earth.
It shows the universe is expanding.
It proves the existence of intelligent life.
What is cosmic background microwave radiation evidence of?
The presence of craters on Earth
The early stages of the universe
The formation of solar systems
The existence of intelligent life
Which factor allowed the pace of evolution to change over Earth’s history?
Changes in oxygen levels
The expansion of the universe
The presence of craters
The redshift in galaxy spectra
What role does water play in the differences in crater visibility between Earth and other solar objects?
Water increases the number of craters.
Water erodes craters over time.
Water prevents asteroid collisions.
Water creates new craters.
How do scientists know that some minerals in Moon rocks and Earth rocks are the same age?
They formed in the same type of rock layers.
They have identical chemical compositions.
They contain the same ratio of uranium-238 to lead-206.
They were found at the same depth below the surface.
What evidence supports the claim that the universe has been expanding?
Changes in oxygen levels
The redshift in galaxy spectra
The presence of craters on Mars
The ratio of hydrogen and helium in the universe
What is the primary factor that impacts the stability of Earth’s systems after asteroid collisions?
The structure of water on Earth
The size of the asteroid
The feedback mechanisms between Earth’s systems
The presence of intelligent life
What is the purpose of analyzing fossil and geologic evidence in understanding Earth’s history?
To prove the existence of intelligent life
To explain the redshift in galaxy spectra
To identify the presence of craters
To construct a timeline of evolutionary events
What is the role of feedback mechanisms in Earth’s systems?
They prevent asteroid collisions.
They increase the number of craters on Earth.
They explain the redshift in galaxy spectra.
They contribute to the coevolution of life and Earth’s systems.
What argument can be made about intelligent life based on models of the universe’s origin?
Intelligent life is unrelated to the universe’s origin.
Intelligent life exists only on Earth.
Intelligent life is proven to exist in other galaxies.
Intelligent life may exist on other planets.
What does the fossil record primarily reveal about the history of life on Earth?
The presence of craters on the Moon
Changes in species over time
The ratio of hydrogen to helium
The expansion of the universe
Which is a negative effect on animals at times when Earth's oxygen levels decreased?
The animals were unable to produce as much energy through respiration.
The animals were unable to produce as much energy through photosynthesis.
The animals lost the ability to metabolize calcium.
The predator-prey relationships reversed.
How do mass extinction events influence the diversity of life on Earth?
They increase the number of craters
They reduce the variety of species
They cause the universe to expand
They stabilize oxygen levels
Which evidence suggests that Earth's surface is constantly changing?
Unchanging number of craters on the Moon
Presence of new rock formations and eroded landscapes
Constant hydrogen and helium ratios in Earth's atmosphere
Stable fossil records in all rock layers
What process most contributes to the disappearance of impact craters on Earth's surface?
Redshift in galaxy spectra
Cosmic background microwave radiation
Plate tectonics and erosion
Solar radiation
Which observation provides evidence for the coevolution of life and Earth's systems?
Discovery of water on Mars
Changes in fossil types across different rock layers
Constant oxygen levels throughout Earth's history
Presence of craters on the Moon
What is the main reason ancient craters are more visible on the Moon than on Earth?
The Moon lacks atmosphere and active surface processes
The Moon has more asteroid impacts
The Moon is closer to the Sun
The Moon has higher oxygen levels
Which is used in radioactive dating?
Carbon-14
Index fossils
Hydrochloric acid
Law of superposition
Through relative dating, a geologist finds a fossil that is approximately 10,000 years old. Which radioactive element would geologist use to accurately calculate the fossils age?
Gallium 67 with a half life of 78 hours
Carbon-14 with a half-life of 5,700 years
Plutonium-238 with a half-life of 88 years
Iodine-129 with a half-life of 16 million years
The length of time required for half of the radioactive atoms in a sample to decay is its...
the relative age of something
age
half-life
eon
What percentage of Rubidium-87 will remain after 4 half-lives?
25%
12.5%
6.25%
3.125%
If the original mass of a radioactive isotope was 24 grams, how many grams would remain after 3 half-lives?
Which element is most abundant in the universe as a result of the Big Bang?
Iron
Carbon
Hydrogen
Oxygen
The formation of banded iron rock approx 2.4 billion years ago indicates that the atmosphere was receiving large amounts of oxygen. This observation is evidence of a change that is a direct result of what other change?
The production of greenhouse gases throughout volcanic eruptions more than 3 billion years ago
The evolution of eukaryotes, the first nucleated cells, 1.5 billion years ago.
The appearance of photosynthetic organisms approximately 2.7 billion years ago
The increased burning of fossil fuels by humans over the past 250 years
Which of the following best describes the overall pattern of atmospheric oxygen over the last 600 million years?
Constant increase over time
Steady decline toward the present
Fluctuations with several peaks and drops
Highest levels during the Mesozoic Era
When did primitive photosynthetic organisms add oxygen to Earth's atmosphere?
2.5 billion years ago
65 million years ago
13.7 billion years ago
1.9 billion years ago
What are the two main factors that make Earth unique and able to support life?
Liquid water and oxygen-rich atmosphere
Plate tectonics and a molten metallic core
The right size and the right location
The right time and the right location
According to most scientists, what is the ultimate cause of most mass extinctions?
overhunting
evolution of new species to replace old ones
major change in environment or climate
asteroid impact
How old is this sample?
4.5 billion years old
3.5 billion years old
2.5 billion years old
1.5 billion years old
Compare the surface of the Moon to Earth in terms of evidence for the Late Heavy Bombardment. Why is the evidence more visible on the Moon?
The Moon has no atmosphere or plate tectonics to erase craters
The Moon is closer to the Sun
The Moon is made of different materials
The Moon has more water
What is the Late Heavy Bombardment (LHB) primarily known for?
A period of intense volcanic activity on Earth
A time when many asteroids and comets struck the inner planets
The formation of the first oceans
The extinction of the dinosaurs
