Question 1

The ability of a celestial body to retain an atmosphere would depend mainly on which of the following properties?

Accepted Answer

A)  mass and size 
B)  age and composition 
C)  presence of life-forms on it 
D)  tilt of the axis of rotation 
E)  period of rotation 
A)  mass and size 
B)  age and composition 
C)  presence of life-forms on it 
D)  tilt of the axis of rotation 
E)  period of rotation

Question 2

The evolution of terrestrial life involves which of the following?

Accepted Answer

A)  mechanisms of change 
B)  mutation 
C)  heredity 
D)  natural selection 
E)  all of these 
A)  mechanisms of change 
B)  mutation 
C)  heredity 
D)  natural selection 
E)  all of these

Question 3

How did the presence of cyanobacteria on Earth in the past enable the later appearance of more advanced life-forms, such as humans?

Accepted Answer

A)  They absorbed harmful chemicals, making the air safer. 
B)  They initiated the oxygenation of the atmosphere. 
C)  They fertilized the soil to let plants grow. 
D)  They increased the carbon dioxide in the atmosphere, causing the greenhouse effect. 
E)  They "ate" plants, creating the first digestive systems on Earth. 
A)  They absorbed harmful chemicals, making the air safer. 
B)  They initiated the oxygenation of the atmosphere. 
C)  They fertilized the soil to let plants grow. 
D)  They increased the carbon dioxide in the atmosphere, causing the greenhouse effect. 
E)  They "ate" plants, creating the first digestive systems on Earth.

Question 4

Briefly explain the various factors that differentiate life from other natural, physical processes.

Accepted Answer

In general,life reproduces,modifies its

Question 5

Why are high-mass stars not expected to have planets with advanced/intelligent life-forms?

Accepted Answer

A)  High-mass stars are short-lived, hence evolution has less time to happen. 
B)  High-mass stars are too big, and their habitable zone is very narrow. 
C)  High-mass stars are too hot, and their habitable zone is too far from them. 
D)  High-mass stars are too blue, and intelligent life-forms can see only white light. 
E)  High-mass stars don't form planets around them. 
A)  High-mass stars are short-lived, hence evolution has less time to happen. 
B)  High-mass stars are too big, and their habitable zone is very narrow. 
C)  High-mass stars are too hot, and their habitable zone is too far from them. 
D)  High-mass stars are too blue, and intelligent life-forms can see only white light. 
E)  High-mass stars don't form planets around them.

Question 6

Using the figure below, explain which types of events necessarily preceded the formation of our Solar System in order for the four main chemical elements of life to be present.

Accepted Answer

Clearly,the Big Bang was necessary,and p

Question 7

Which of the following bodies of the Solar System has not yet been landed upon by spacecraft?

Accepted Answer

A)  Europa 
B)  Titan 
C)  the Moon 
D)  Mars 
E)  Venus 
A)  Europa 
B)  Titan 
C)  the Moon 
D)  Mars 
E)  Venus

Question 8

The Solar System body to which humans have dedicated the largest number of landing missions so far is

Accepted Answer

A)  Europa. 
B)  Titan. 
C)  Enceladus. 
D)  Mars. 
E)  Venus. 
A)  Europa. 
B)  Titan. 
C)  Enceladus. 
D)  Mars. 
E)  Venus.

Question 9

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

Accepted Answer

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

Question 10

Which factors in the Drake equation can be better understood by studying large numbers of exoplanets?

Accepted Answer

The increasing number of discovered plan

Question 11

Which of the following is expected to be a strong requirement for supporting life?

Accepted Answer

A)  tidal forces 
B)  photosynthesis 
C)  water in liquid form 
D)  an atmosphere 
E)  lightning strikes 
A)  tidal forces 
B)  photosynthesis 
C)  water in liquid form 
D)  an atmosphere 
E)  lightning strikes

Question 12

What is SETI, what is its main objective, and how does it plan to achieve it?

Accepted Answer

SETI stands for Search for Extraterrestr

Question 13

The main goal of the Allen Telescope Array is to search for

Accepted Answer

A)  silicon-based life-forms in other planetary systems. 
B)  electromagnetic signals from civilizations inhabiting habitable planets. 
C)  exoplanets in other galaxies. 
D)  dark energy. 
E)  man-made satellites drifting out of control around Earth. 
A)  silicon-based life-forms in other planetary systems. 
B)  electromagnetic signals from civilizations inhabiting habitable planets. 
C)  exoplanets in other galaxies. 
D)  dark energy. 
E)  man-made satellites drifting out of control around Earth.

Question 14

What does the word "intelligent" mean, with respect to life in the universe?

Accepted Answer

For the Drake equation,"intelligent" ref

Question 15

In the context of self-replication of molecules, if each of them is successfully copying itself every 2 minutes, how long does it take to have a population growth factor of the order of a billion?

Accepted Answer

A)  1 hour 
B)  2 hours 
C)  10 minutes 
D)  2 minutes 
E)  2 billion minutes 
A)  1 hour 
B)  2 hours 
C)  10 minutes 
D)  2 minutes 
E)  2 billion minutes

Question 16

Which of the following is an example of an extremophile?

Accepted Answer

A)  organisms that thrive at high temperatures 
B)  organisms that thrive without light 
C)  organisms that thrive in highly acidic environments 
D)  organisms that thrive in environments with high radiation levels 
E)  All of these are examples of extremophiles. 
A)  organisms that thrive at high temperatures 
B)  organisms that thrive without light 
C)  organisms that thrive in highly acidic environments 
D)  organisms that thrive in environments with high radiation levels 
E)  All of these are examples of extremophiles.

Question 17

What would be the main factors determining whether water can exist in a liquid state on the surface of a planet?

Accepted Answer

A)  the presence of photosynthetic and highly intelligent life-forms 
B)  the age and mass of the central star 
C)  the atmospheric pressure and temperature on the planetary surface 
D)  the color and temperature of the central star 
E)  the existence of carbon-based biology 
A)  the presence of photosynthetic and highly intelligent life-forms 
B)  the age and mass of the central star 
C)  the atmospheric pressure and temperature on the planetary surface 
D)  the color and temperature of the central star 
E)  the existence of carbon-based biology

Question 18

What makes Titan an attractive target in the search for life-forms?

Accepted Answer

Titan has a thick atmosphere r

Question 19

In 1974, astronomers sent a message toward globular cluster M13.If life exists there, and it returns our signal, we won't receive it for at least another 50,000 years.Why?

Accepted Answer

A)  It will take that long for the space probe carrying our signal to reach the life-forms there. 
B)  Based on the age of the stars in M13, we anticipate it would take that long for a civilization to evolve enough to interpret and respond to our signal. 
C)  M13 is far enough away that even light takes a very long time to reach it. 
D)  It will take that long before our Solar System and M13 are properly aligned again. 
E)  The universe will have expanded substantially after M13 receives our message; therefore, it will take much longer for the response to make it back to Earth. 
A)  It will take that long for the space probe carrying our signal to reach the life-forms there. 
B)  Based on the age of the stars in M13, we anticipate it would take that long for a civilization to evolve enough to interpret and respond to our signal. 
C)  M13 is far enough away that even light takes a very long time to reach it. 
D)  It will take that long before our Solar System and M13 are properly aligned again. 
E)  The universe will have expanded substantially after M13 receives our message; therefore, it will take much longer for the response to make it back to Earth.

Question 20

The chemical element that forms the "backbone" of DNA molecules is

Accepted Answer

A)  carbon. 
B)  nitrogen. 
C)  silicon. 
D)  helium. 
E)  oxygen. 
A)  carbon. 
B)  nitrogen. 
C)  silicon. 
D)  helium. 
E)  oxygen.

Exam 24: Life

The ability of a celestial body to retain an atmosphere would depend mainly on which of the following properties?

The evolution of terrestrial life involves which of the following?

How did the presence of cyanobacteria on Earth in the past enable the later appearance of more advanced life-forms, such as humans?

Briefly explain the various factors that differentiate life from other natural, physical processes.

Why are high-mass stars not expected to have planets with advanced/intelligent life-forms?

Using the figure below, explain which types of events necessarily preceded the formation of our Solar System in order for the four main chemical elements of life to be present.

Which of the following bodies of the Solar System has not yet been landed upon by spacecraft?

The Solar System body to which humans have dedicated the largest number of landing missions so far is

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

Which factors in the Drake equation can be better understood by studying large numbers of exoplanets?

Which of the following is expected to be a strong requirement for supporting life?

What is SETI, what is its main objective, and how does it plan to achieve it?

The main goal of the Allen Telescope Array is to search for

What does the word "intelligent" mean, with respect to life in the universe?

In the context of self-replication of molecules, if each of them is successfully copying itself every 2 minutes, how long does it take to have a population growth factor of the order of a billion?

Which of the following is an example of an extremophile?

What would be the main factors determining whether water can exist in a liquid state on the surface of a planet?

What makes Titan an attractive target in the search for life-forms?

In 1974, astronomers sent a message toward globular cluster M13.If life exists there, and it returns our signal, we won't receive it for at least another 50,000 years.Why?

The chemical element that forms the "backbone" of DNA molecules is

Thinking Like an Astronomer

Patterns in the Skymotions of Earth and the Moon

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Formation of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquidthe Giant Planets

Planetary Moons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Our Starthe Sun

The Interstellar Medium and Star Formation

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

Galaxies

The Milky Waya Normal Spiral Galaxy

The Expanding Universe

Cosmology

Large-Scale Structure in the Universe

Filters