Question 1

All of the terms in the Drake equation are estimates.In the next decade,which of these estimates is likely to improve the most because of better observational data?

Accepted Answer

A) number of stars in the Milky Way 
B) fraction of stars with planets 
C) number of planets per star in the habitable zone 
D) fraction of planets where life evolves to intelligence 
A) number of stars in the Milky Way 
B) fraction of stars with planets 
C) number of planets per star in the habitable zone 
D) fraction of planets where life evolves to intelligence C

Question 2

The wavelengths that are most likely for communication with other civilizations are those in the water hole.

Accepted Answer

A) True 
 B)False  True

Question 3

A single human cell encloses about 1.5 metres of DNA,containing 4.5 billion base pairs.How far apart are these base pairs in the DNA?

Accepted Answer

A) 3.3×10¹⁰ nm 
B) 3×10⁹ nm 
C) 300 nm 
D) 0.34 nm 
A) 3.3×10¹⁰ nm 
B) 3×10⁹ nm 
C) 300 nm 
D) 0.34 nm D

Question 4

How do we usually refer to deoxyribonucleic acid?

Accepted Answer

A) as vitamin D 
B) as reproductive enzymes 
C) as RNA 
D) as DNA 
A) as vitamin D 
B) as reproductive enzymes 
C) as RNA 
D) as DNA

Question 5

The ____________________ is a region around a star where liquid water can exist.

Accepted Answer

The answer of The ____________________ is a region around a...

Question 6

What is important about the habitable zone around a star that makes astronomers believe life could exist there?

Accepted Answer

A) The level of UV radiation from the star is minimal in the habitable zone. 
B) Only in the habitable zone can complex organic molecules be found. 
C) Planets in the habitable zone will always have an oxygen atmosphere. 
D) In the habitable zone, water can exist as a liquid. 
A) The level of UV radiation from the star is minimal in the habitable zone. 
B) Only in the habitable zone can complex organic molecules be found. 
C) Planets in the habitable zone will always have an oxygen atmosphere. 
D) In the habitable zone, water can exist as a liquid.

Question 7

Even if societies on stars in distant galaxies survive at a technological level for only 10 years,that is long enough to establish two-way communication with them.

Accepted Answer

A) True 
 B)False

Question 8

The Miller experiment created synthetic DNA.

Accepted Answer

A) True 
 B)False

Question 9

The Viking spacecraft searched for life on Mars by looking for the effects of life in the upper atmosphere.

Accepted Answer

A) True 
 B)False

Question 10

Why do some scientists think that the idea of the habitable zone as a fixed distance range from a star is too restrictive?

Accepted Answer

A) Changes in stars' brightness might change the position of habitable zones. 
B) Many forms of life do not require liquid water. 
C) Planets may not always keep a constant distance from their star. 
D) Liquid water can be maintained by tidal heating. 
A) Changes in stars' brightness might change the position of habitable zones. 
B) Many forms of life do not require liquid water. 
C) Planets may not always keep a constant distance from their star. 
D) Liquid water can be maintained by tidal heating.

Question 11

The most important factor necessary for life to form appears to be the existence of ____________________ on the surface of the planet.

Accepted Answer

The answer of The most important factor necessary for life...

Question 12

Which of the following limits the number of technological civilizations in our galaxy?

Accepted Answer

A) the lifetime of M dwarf stars 
B) the number of satellite galaxies of the Milky Way 
C) the number of planets per star in a habitable zone for longer than a few billion years 
D) the fraction of civilizations that wish to communicate with others 
A) the lifetime of M dwarf stars 
B) the number of satellite galaxies of the Milky Way 
C) the number of planets per star in a habitable zone for longer than a few billion years 
D) the fraction of civilizations that wish to communicate with others

Question 13

Which of the following is used by all known forms of life on Earth as a medium for chemical reactions?

Accepted Answer

A) gaseous helium 
B) frozen carbon dioxide 
C) liquid water 
D) frozen water 
A) gaseous helium 
B) frozen carbon dioxide 
C) liquid water 
D) frozen water

Question 14

What is the significance of the Miller experiment?

Accepted Answer

The Miller experiment, also known as the

Question 15

What was happening elsewhere in the universe when the first complex life appeared on Earth?

Accepted Answer

A) The Milky Way galaxy was just forming. 
B) Some of the A-type stars we see in the sky today were still forming. 
C) The light we see from stars on the other side of the Milky Way was just starting its journey. 
D) The late heavy bombardment in our solar system had just finished. 
A) The Milky Way galaxy was just forming. 
B) Some of the A-type stars we see in the sky today were still forming. 
C) The light we see from stars on the other side of the Milky Way was just starting its journey. 
D) The late heavy bombardment in our solar system had just finished.

Question 16

The portion of the electromagnetic spectrum between the 21 cm line of neutral hydrogen and the 18 cm line of OH is known as the ____________________.

Accepted Answer

The answer of The portion of the electromagnetic spectrum between...

Question 17

What is an offspring born with altered DNA due to radioactivity,cosmic rays,or errors in reproduction called?

Accepted Answer

A) a mutant 
B) a new species 
C) a mule 
D) a cross-breed 
A) a mutant 
B) a new species 
C) a mule 
D) a cross-breed

Question 18

The first complex life appeared on Earth about 0.5 billion years ago.What period was that?

Accepted Answer

A) the Jurassic Period 
B) the Cambrian Period 
C) the Precambrian Period 
D) the Neolithic Period 
A) the Jurassic Period 
B) the Cambrian Period 
C) the Precambrian Period 
D) the Neolithic Period

Question 19

Suppose that a lifeform was discovered on Mars,and all of the different individuals in this lifeform had exactly the same genetic material.Why would biologists find this surprising?

Accepted Answer

A) Mars has never had conditions suitable for life. 
B) Lifeforms on other planets are not expected to have genetic material. 
C) Mars has had varying environmental conditions through its history. 
D) Random variations in genetic material are expected to help lifeforms adapt. 
A) Mars has never had conditions suitable for life. 
B) Lifeforms on other planets are not expected to have genetic material. 
C) Mars has had varying environmental conditions through its history. 
D) Random variations in genetic material are expected to help lifeforms adapt.

Question 20

When considering the possible number of technologically advanced civilizations in our galaxy,which of the following factors is it useful to consider?

Accepted Answer

A) the average lifespan of an alien 
B) the average lifespan of the civilization 
C) the distance to the civilization's planet 
D) the type of advanced communication they use 
A) the average lifespan of an alien 
B) the average lifespan of the civilization 
C) the distance to the civilization's planet 
D) the type of advanced communication they use

All of the terms in the Drake equation are estimates.In the next decade,which of these estimates is likely to improve the most because of better observational data?

The wavelengths that are most likely for communication with other civilizations are those in the water hole.

A single human cell encloses about 1.5 metres of DNA,containing 4.5 billion base pairs.How far apart are these base pairs in the DNA?

How do we usually refer to deoxyribonucleic acid?

The ____________________ is a region around a star where liquid water can exist.

What is important about the habitable zone around a star that makes astronomers believe life could exist there?

Even if societies on stars in distant galaxies survive at a technological level for only 10 years,that is long enough to establish two-way communication with them.

The Miller experiment created synthetic DNA.

The Viking spacecraft searched for life on Mars by looking for the effects of life in the upper atmosphere.

Why do some scientists think that the idea of the habitable zone as a fixed distance range from a star is too restrictive?

The most important factor necessary for life to form appears to be the existence of ____________________ on the surface of the planet.

Which of the following limits the number of technological civilizations in our galaxy?

Which of the following is used by all known forms of life on Earth as a medium for chemical reactions?

What is the significance of the Miller experiment?

What was happening elsewhere in the universe when the first complex life appeared on Earth?

The portion of the electromagnetic spectrum between the 21 cm line of neutral hydrogen and the 18 cm line of OH is known as the ____________________.

What is an offspring born with altered DNA due to radioactivity,cosmic rays,or errors in reproduction called?

The first complex life appeared on Earth about 0.5 billion years ago.What period was that?

Suppose that a lifeform was discovered on Mars,and all of the different individuals in this lifeform had exactly the same genetic material.Why would biologists find this surprising?

When considering the possible number of technologically advanced civilizations in our galaxy,which of the following factors is it useful to consider?

The Scale of the Cosmos

User's Guide to the Sky

The Origin of Modern Astronomy

Astronomical Telescopes and Instruments

Sun Light and Sun Atoms

The Family of Stars

The Structure and Formation of Stars

The Deaths of Stars

The Milky Way Galaxy

Galaxies

Cosmology in the 21st Century

The Origin of the Solar System

Comparative Planetology of the Terrestrial Planets

Comparative Planetology of the Jovian Planets

Filters

Exam 15: Life on Other Worlds

All of the terms in the Drake equation are estimates.In the next decade,which of these estimates is likely to improve the most because of better observational data?

The wavelengths that are most likely for communication with other civilizations are those in the water hole.

A single human cell encloses about 1.5 metres of DNA,containing 4.5 billion base pairs.How far apart are these base pairs in the DNA?

How do we usually refer to deoxyribonucleic acid?

The ____________________ is a region around a star where liquid water can exist.

What is important about the habitable zone around a star that makes astronomers believe life could exist there?

Even if societies on stars in distant galaxies survive at a technological level for only 10 years,that is long enough to establish two-way communication with them.

The Miller experiment created synthetic DNA.

The Viking spacecraft searched for life on Mars by looking for the effects of life in the upper atmosphere.

Why do some scientists think that the idea of the habitable zone as a fixed distance range from a star is too restrictive?

The most important factor necessary for life to form appears to be the existence of ____________________ on the surface of the planet.

Which of the following limits the number of technological civilizations in our galaxy?

Which of the following is used by all known forms of life on Earth as a medium for chemical reactions?

What is the significance of the Miller experiment?

What was happening elsewhere in the universe when the first complex life appeared on Earth?

The portion of the electromagnetic spectrum between the 21 cm line of neutral hydrogen and the 18 cm line of OH is known as the ____________________.

What is an offspring born with altered DNA due to radioactivity,cosmic rays,or errors in reproduction called?

The first complex life appeared on Earth about 0.5 billion years ago.What period was that?

Suppose that a lifeform was discovered on Mars,and all of the different individuals in this lifeform had exactly the same genetic material.Why would biologists find this surprising?

When considering the possible number of technologically advanced civilizations in our galaxy,which of the following factors is it useful to consider?

The Scale of the Cosmos

User's Guide to the Sky

The Origin of Modern Astronomy

Astronomical Telescopes and Instruments

Sun Light and Sun Atoms

The Family of Stars

The Structure and Formation of Stars

The Deaths of Stars

The Milky Way Galaxy

Galaxies

Cosmology in the 21st Century

The Origin of the Solar System

Comparative Planetology of the Terrestrial Planets

Comparative Planetology of the Jovian Planets

Filters