Question 1

Based on what you know of the Earth's evolution, what percent of Earth-like planets in a star cluster with an age of 2 billion years likely has intelligent life?

Accepted Answer

A)   0
B)   10 percent
C)   30 percent
D)   50 percent
E)   100 percent

Question 2

Mutations always lead to improvements in an organism's ability to survive and reproduce.

Accepted Answer

A) True 
 B)False

Question 3

When the Pioneer and Voyager spacecraft were launched into space in the 1970s, they were outfitted with messages describing where they came from. Why is it fairly unlikely that an alien civilization will use them to find us?

Accepted Answer

A)   The extremely large distances between stars means it will take a very long time before they reach another solar system.
B)   They will probably rust and fall apart as they get older.
C)   They will burn up as the Sun's gravity pulls them in.
D)   They will likely run into Kuiper Belt objects before they leave the Solar System.
E)   They are moving so fast through space that they would be very difficult to catch.

Question 4

As living organisms evolved to become more complex during the history of the Earth, did this violate the second law of thermodynamics?

Accepted Answer

As a specific organism evolved...

Question 5

Using life on Earth as an example, calculate the maximum likelihood that any technologically advanced civilization that arose still exists on its home planet today.

Accepted Answer

The maximum value of L is simply the lif...

Question 6

Which one of the following is NOT one of the three categories of terrestrial life based on their DNA characteristics?

Accepted Answer

A)   bacteria
B)   eukarya
C)   archaea
D)   fungi

Question 7

If the entire history of the universe were scaled to fit into one day, what time of day would microorganisms first form, oxygen start becoming a significant component of the atmosphere, and humans split off from their genetic ancestors?

Accepted Answer

The Earth is 4.5 billion years old. Micr...

Question 8

Why would the 21-cm line be a good place to search for signals from intelligent life in the universe?

Accepted Answer

Other civilizations might decide to send...

Question 9

We search for intelligent life in the universe most effectively by:

Accepted Answer

A)   sending out spacecraft with messages on them
B)   using radio telescopes to search for radio signals
C)   monitoring ultraviolet radiation emitted by stars
D)   sending spacecraft to explore other worlds
E)   all of the above

Question 10

Scientists have shown that ammonia and methane, mixed together with liquid water and either hydrogen, carbon dioxide, or nitrogen, and exposed to electrical sparks, can produce some of the amino acids essential for life.

Accepted Answer

A) True 
 B)False

Question 11

What was the goal of the experiment depicted below?

Accepted Answer

A)   to create a microorganism
B)   to simulate the formation of Earth
C)   to simulate the Big Bang
D)   to simulate the early universe
E)   to simulate the formation of the building blocks of life

Question 12

Complex microorganisms that have complex DNA enclosed in a cell nucleus are called:

Accepted Answer

A)   algae
B)   bacteria
C)   fungi
D)   eukaryotes
E)   prokaryotes

Question 13

Where do we think life first formed on the Earth?

Accepted Answer

A)   in the air
B)   in the oceans
C)   on land
D)   on meteoroids that carried microorganisms to Earth
E)   deep in the interior of Earth

Question 14

What determines whether or not a specific mutation is passed on to future generations?

Accepted Answer

Mutations can be either good o...

Question 15

Animals are most closely related to which of the following branches?

Accepted Answer

A)   bacteria
B)   archaea
C)   flagellates
D)   fungi
E)   cyanobacteria

Question 16

Which of the following Solar System objects is NOT a good candidate for future searches for life?

Accepted Answer

A)   Mars, because it once had liquid water on the surface
B)   Jupiter's moon Europa, because it appears to have liquid water under its frozen surface
C)   Saturn's moon Titan, because it has an atmosphere containing many organic molecules
D)   Pluto, because a large portion of it is made of water ice
E)   Saturn's moon Enceladus, because its cryovolcanoes indicate that it has liquid water under the surface

Question 17

If we model the history of the universe as a single day, at what time would the first Homo sapiens appear?

Accepted Answer

A)   11:59:58.5 P.M.
B)   11:59:20 P.M.
C)   11:35:00 P.M.
D)   10:00 P.M.
E)   6:00 P.M.

Question 18

The habitable zone around a star depends most on its:

Accepted Answer

A)   mass and age
B)   radius and distance
C)   age and radius
D)   color and distance
E)   luminosity and velocity

Question 19

Some forms of life on Earth are silicon-based.

Accepted Answer

A) True 
 B)False

Question 20

The field of astrobiology uses our knowledge of ___________ to study life in the universe.

Accepted Answer

A)   biology
B)   chemistry
C)   physics
D)   astronomy
E)   all of the above

Exam 24: Life

What determines whether or not a specific mutation is passed on to future generations?

Correct AnswerverifiedMutations can be either good o...View AnswerShow Answer

Some forms of life on Earth are silicon-based.

Correct AnswerverifiedShow Answer

Using life on Earth as an example, calculate the maximum likelihood that any technologically advanced civilization that arose still exists on its home planet today.

Correct AnswerverifiedThe maximum value of L is simply the lif...View AnswerShow Answer

Scientists have shown that ammonia and methane, mixed together with liquid water and either hydrogen, carbon dioxide, or nitrogen, and exposed to electrical sparks, can produce some of the amino acids essential for life.

Correct AnswerverifiedShow Answer

Why would the 21-cm line be a good place to search for signals from intelligent life in the universe?

Correct AnswerverifiedOther civilizations might decide to send...View AnswerShow Answer

The field of astrobiology uses our knowledge of ___________ to study life in the universe.

Correct AnswerverifiedShow Answer

What was the goal of the experiment depicted below?

Correct AnswerverifiedShow Answer

Based on what you know of the Earth's evolution, what percent of Earth-like planets in a star cluster with an age of 2 billion years likely has intelligent life?

Correct AnswerverifiedShow Answer

If we model the history of the universe as a single day, at what time would the first Homo sapiens appear?

Correct AnswerverifiedShow Answer

Animals are most closely related to which of the following branches?

Correct AnswerverifiedShow Answer

Mutations always lead to improvements in an organism's ability to survive and reproduce.

Correct AnswerverifiedShow Answer

Which one of the following is NOT one of the three categories of terrestrial life based on their DNA characteristics?

Correct AnswerverifiedShow Answer

Which of the following Solar System objects is NOT a good candidate for future searches for life?

Correct AnswerverifiedShow Answer

Complex microorganisms that have complex DNA enclosed in a cell nucleus are called:

Correct AnswerverifiedShow Answer

If the entire history of the universe were scaled to fit into one day, what time of day would microorganisms first form, oxygen start becoming a significant component of the atmosphere, and humans split off from their genetic ancestors?

Correct AnswerverifiedThe Earth is 4.5 billion years old. Micr...View AnswerShow Answer

The habitable zone around a star depends most on its:

Correct AnswerverifiedShow Answer

When the Pioneer and Voyager spacecraft were launched into space in the 1970s, they were outfitted with messages describing where they came from. Why is it fairly unlikely that an alien civilization will use them to find us?

Correct AnswerverifiedShow Answer

Where do we think life first formed on the Earth?

Correct AnswerverifiedShow Answer

We search for intelligent life in the universe most effectively by:

Correct AnswerverifiedShow Answer

As living organisms evolved to become more complex during the history of the Earth, did this violate the second law of thermodynamics?

Correct AnswerverifiedAs a specific organism evolved...View AnswerShow Answer

Correct Answer
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Mutations can be either good o...
View Answer

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The maximum value of L is simply the lif...
View Answer

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Other civilizations might decide to send...
View Answer

Correct Answer
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Correct Answer
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The Earth is 4.5 billion years old. Micr...
View Answer

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
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Correct Answer
verified
As a specific organism evolved...
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