Question 1

Why is liquid water considered essential for life to form?

Accepted Answer

A)  Water is a highly effective solvent in biochemical reactions. 
B)  Most of Earth's surface is covered in water. 
C)  Liquid water defines the habitability zone. 
D)  Water is the key component of organic molecules. 
A)  Water is a highly effective solvent in biochemical reactions. 
B)  Most of Earth's surface is covered in water. 
C)  Liquid water defines the habitability zone. 
D)  Water is the key component of organic molecules. A

Question 2

Which of the following factors does NOT appear in the Drake equation?

Accepted Answer

A)  the number of stars in the Milky Way 
B)  the fraction of life-bearing planets on which intelligence evolves 
C)  the average lifetime of a technologically advanced civilization 
D)  the average delay between the formation of a planet and the appearance of life 
A)  the number of stars in the Milky Way 
B)  the fraction of life-bearing planets on which intelligence evolves 
C)  the average lifetime of a technologically advanced civilization 
D)  the average delay between the formation of a planet and the appearance of life D

Question 3

Which of the following is a basic feature of living things?

Accepted Answer

A)  metabolism 
B)  composed of proteins 
C)  sexual reproduction 
D)  cell nuclei 
A)  metabolism 
B)  composed of proteins 
C)  sexual reproduction 
D)  cell nuclei A

Question 4

What is one potential resolution to Fermi's paradox,if intelligent extraterrestrial life does exist?

Accepted Answer

It may be advantageous to hide

Question 5

The smallest self-replicating RNA molecule is built from 24 nucleotides.How many such molecules could there be containing the same number of nucleotides?

Accepted Answer

A)  224 
B)  424 
C)  242 
D)  244 
A)  224 
B)  424 
C)  242 
D)  244

Question 6

What are the advantages of searching for extraterrestrial signals in the radio band?

Accepted Answer

Radio waves can prop

Question 7

Which of the following is a common way in which genes in a population change?

Accepted Answer

A)  injury 
B)  aging 
C)  sexual reproduction 
D)  natural selection 
A)  injury 
B)  aging 
C)  sexual reproduction 
D)  natural selection

Question 8

Why did the oxygen content of the atmosphere increase dramatically 2.5 billion years ago?

Accepted Answer

A)  The first life appeared on Earth. 
B)  The sea and earth became saturated with oxygen. 
C)  The Late Heavy Bombardment occurred. 
D)  The Cambrian explosion led to diverse plant life. 
A)  The first life appeared on Earth. 
B)  The sea and earth became saturated with oxygen. 
C)  The Late Heavy Bombardment occurred. 
D)  The Cambrian explosion led to diverse plant life.

Question 9

Suppose the inner edge of a star's habitable zone is at 2 AU.The star suddenly increases its luminosity by a factor of 4.Where is the inner edge of the habitable zone now?

Accepted Answer

A)  1 AU 
B)  2 AU 
C)  4 AU 
D)  8 AU 
A)  1 AU 
B)  2 AU 
C)  4 AU 
D)  8 AU

Question 10

What is responsible for the oxygen in Earth's atmosphere?

Accepted Answer

The answer of What is responsible for the oxygen in...

Question 11

Describe the physical structure of a DNA molecule.

Accepted Answer

DNA consists of two

Question 12

The Drake equation estimates the:

Accepted Answer

A)  number of planets hosting life in the Milky Way. 
B)  number of technologically advanced civilizations in the Milky Way. 
C)  likelihood of observing a signature of life around a star. 
D)  likelihood of observing a radio signal from an extraterrestrial civilization. 
A)  number of planets hosting life in the Milky Way. 
B)  number of technologically advanced civilizations in the Milky Way. 
C)  likelihood of observing a signature of life around a star. 
D)  likelihood of observing a radio signal from an extraterrestrial civilization.

Question 13

Why do astronomers search for signals of extraterrestrial intelligence at a wavelength of 21 centimeters?

Accepted Answer

A)  At 21 centimeters there is very little contamination from other material in the galaxy. 
B)  Hydrogen emits radiation at 21 centimeters. 
C)  Oxygen emits radiation at 21 centimeters. 
D)  Greenhouse gases emit radiation at 21 centimeters. 
A)  At 21 centimeters there is very little contamination from other material in the galaxy. 
B)  Hydrogen emits radiation at 21 centimeters. 
C)  Oxygen emits radiation at 21 centimeters. 
D)  Greenhouse gases emit radiation at 21 centimeters.

Question 14

What are the four ways in which genes and their distribution within populations can change over time?

Accepted Answer

Mutation,migration,g

Question 15

How has the discovery of extremophiles changed our understanding of life in the universe?

Accepted Answer

Extremophiles demonstrate that

Question 16

What defines the habitability zone around a star?

Accepted Answer

The presence of liqu

Question 17

According to our present astronomical understanding,what astronomical environment is essential for life to begin and develop under evolution?

Accepted Answer

A world,ei

Question 18

A lock requires a three-number sequence to open,with each number ranging from 1 to 10.If a thief requires three seconds to try any one combination,what is the maximum number of seconds before the thief opens the lock?

Accepted Answer

A)  310 
B)  103 
C)  3 × 103 
D)  106 
A)  310 
B)  103 
C)  3 × 103 
D)  106

Question 19

Which of the following provides the basic energy source for some systems of life on Earth?

Accepted Answer

A)  crystal stress 
B)  plant life 
C)  wind energy 
D)  geothermal energy 
A)  crystal stress 
B)  plant life 
C)  wind energy 
D)  geothermal energy

Question 20

The development of antibiotic resistance among bacterial populations is a consequence of:

Accepted Answer

A)  lateral gene transfer. 
B)  mutation. 
C)  natural selection. 
D)  all of the above. 
A)  lateral gene transfer. 
B)  mutation. 
C)  natural selection. 
D)  all of the above.

Why is liquid water considered essential for life to form?

Which of the following factors does NOT appear in the Drake equation?

Which of the following is a basic feature of living things?

What is one potential resolution to Fermi's paradox,if intelligent extraterrestrial life does exist?

The smallest self-replicating RNA molecule is built from 24 nucleotides.How many such molecules could there be containing the same number of nucleotides?

What are the advantages of searching for extraterrestrial signals in the radio band?

Which of the following is a common way in which genes in a population change?

Why did the oxygen content of the atmosphere increase dramatically 2.5 billion years ago?

Suppose the inner edge of a star's habitable zone is at 2 AU.The star suddenly increases its luminosity by a factor of 4.Where is the inner edge of the habitable zone now?

What is responsible for the oxygen in Earth's atmosphere?

Describe the physical structure of a DNA molecule.

The Drake equation estimates the:

Why do astronomers search for signals of extraterrestrial intelligence at a wavelength of 21 centimeters?

What are the four ways in which genes and their distribution within populations can change over time?

How has the discovery of extremophiles changed our understanding of life in the universe?

What defines the habitability zone around a star?

According to our present astronomical understanding,what astronomical environment is essential for life to begin and develop under evolution?

A lock requires a three-number sequence to open,with each number ranging from 1 to 10.If a thief requires three seconds to try any one combination,what is the maximum number of seconds before the thief opens the lock?

Which of the following provides the basic energy source for some systems of life on Earth?

The development of antibiotic resistance among bacterial populations is a consequence of:

Getting Started: Science, astronomy, and Being Human

A Universe Made, a Universe Discovered

A Universe of Universal Laws

A Universe of Universal Laws

The Architecture and Birth of Planetary Systems

Home Base: Earth and Moon

Sibling Worlds: Mercury, Venus, and Mars

Gas, ice, and Stone: the Outer Planets

The Sun As a Star

Measuring the Stars: the Main Sequence and Its Meaning

Nursery of the Stars: the Interstellar Medium and Star Formation

To the Graveyard of Stars: the End Points of Stellar Evolution

Down the Rabbit Hole: Relativity and Black Holes

Our City of Stars: the Milky Way

A Universe of Galaxies

The Cosmic Web: the Large-Scale Structure of the Universe

Cosmology

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Exam 9: Life and the Search for Habitable Worlds

Why is liquid water considered essential for life to form?

Which of the following factors does NOT appear in the Drake equation?

Which of the following is a basic feature of living things?

What is one potential resolution to Fermi's paradox,if intelligent extraterrestrial life does exist?

The smallest self-replicating RNA molecule is built from 24 nucleotides.How many such molecules could there be containing the same number of nucleotides?

What are the advantages of searching for extraterrestrial signals in the radio band?

Which of the following is a common way in which genes in a population change?

Why did the oxygen content of the atmosphere increase dramatically 2.5 billion years ago?

Suppose the inner edge of a star's habitable zone is at 2 AU.The star suddenly increases its luminosity by a factor of 4.Where is the inner edge of the habitable zone now?

What is responsible for the oxygen in Earth's atmosphere?

Describe the physical structure of a DNA molecule.

The Drake equation estimates the:

Why do astronomers search for signals of extraterrestrial intelligence at a wavelength of 21 centimeters?

What are the four ways in which genes and their distribution within populations can change over time?

How has the discovery of extremophiles changed our understanding of life in the universe?

What defines the habitability zone around a star?

According to our present astronomical understanding,what astronomical environment is essential for life to begin and develop under evolution?

A lock requires a three-number sequence to open,with each number ranging from 1 to 10.If a thief requires three seconds to try any one combination,what is the maximum number of seconds before the thief opens the lock?

Which of the following provides the basic energy source for some systems of life on Earth?

The development of antibiotic resistance among bacterial populations is a consequence of:

Getting Started: Science, astronomy, and Being Human

A Universe Made, a Universe Discovered

A Universe of Universal Laws

A Universe of Universal Laws

The Architecture and Birth of Planetary Systems

Home Base: Earth and Moon

Sibling Worlds: Mercury, Venus, and Mars

Gas, ice, and Stone: the Outer Planets

The Sun As a Star

Measuring the Stars: the Main Sequence and Its Meaning

Nursery of the Stars: the Interstellar Medium and Star Formation

To the Graveyard of Stars: the End Points of Stellar Evolution

Down the Rabbit Hole: Relativity and Black Holes

Our City of Stars: the Milky Way

A Universe of Galaxies

The Cosmic Web: the Large-Scale Structure of the Universe

Cosmology

Filters