Question 1

The second law of thermodynamics states that:

Accepted Answer

A)  all systems must become more disordered with time 
B)  all systems must become more ordered with time 
C)  some systems can become more ordered if others become less ordered by the same amount or more 
D)  Earth must revolve around the Sun 
E)  energy must always be conserved 
A)  all systems must become more disordered with time 
B)  all systems must become more ordered with time 
C)  some systems can become more ordered if others become less ordered by the same amount or more 
D)  Earth must revolve around the Sun 
E)  energy must always be conserved C

Question 2

SETI's Allen Telescope Array is designed to search ___________ for signs of intelligent life.

Accepted Answer

A)  over a thousand stars 
B)  over a million stars 
C)  over a billion stars 
D)  galaxies in the Local Group 
E)  the 100 closest spiral galaxies 
A)  over a thousand stars 
B)  over a million stars 
C)  over a billion stars 
D)  galaxies in the Local Group 
E)  the 100 closest spiral galaxies B

Question 3

The main goal of the Allen Telescope Array is to search for high redshift galaxies.

Accepted Answer

A) True 
 B)False  False

Question 4

Carbon forms the backbone of our DNA primarily because:

Accepted Answer

A)  it is the most abundant element in the universe after hydrogen and helium 
B)  it reacts easily with oxygen 
C)  it remains solid even at high temperatures 
D)  a carbon atom can bond with up to four atoms at a time 
E)  it can form multiple types of crystal structures 
A)  it is the most abundant element in the universe after hydrogen and helium 
B)  it reacts easily with oxygen 
C)  it remains solid even at high temperatures 
D)  a carbon atom can bond with up to four atoms at a time 
E)  it can form multiple types of crystal structures

Question 5

If the most pessimistic assumptions in the Drake equation were true, we would:

Accepted Answer

A)  have to wait for millions of years to get a message back from the nearest intelligent life 
B)  have to wait for approximately 40 years to get a message back from the nearest intelligent life 
C)  be the only intelligent life in the universe 
D)  need to concentrate on the Andromeda Galaxy when searching for intelligent life 
E)  need to concentrate on the most distant galaxies to find signs of intelligent life 
A)  have to wait for millions of years to get a message back from the nearest intelligent life 
B)  have to wait for approximately 40 years to get a message back from the nearest intelligent life 
C)  be the only intelligent life in the universe 
D)  need to concentrate on the Andromeda Galaxy when searching for intelligent life 
E)  need to concentrate on the most distant galaxies to find signs of intelligent life

Question 6

People argue against the possibility of time travel by saying, "If humans will eventually be able to travel back in time, then where are all the tourists from the future?" This idea is similar to the ___________, only applied to time travel instead of aliens.

Accepted Answer

A)  Drake equation 
B)  cosmological principle 
C)  Fermi paradox 
D)  Urey-Miller experiment 
E)  evolutionary tree of life 
A)  Drake equation 
B)  cosmological principle 
C)  Fermi paradox 
D)  Urey-Miller experiment 
E)  evolutionary tree of life

Question 7

Which of the following is a likely source of the energy needed to create the first life on Earth?

Accepted Answer

A)  land volcanoes 
B)  asteroid impacts 
C)  lightning 
D)  fire 
E)  earthquakes 
A)  land volcanoes 
B)  asteroid impacts 
C)  lightning 
D)  fire 
E)  earthquakes

Question 8

Why did the presence of cyanobacteria on Earth in the past allow humans to exist?

Accepted Answer

A)  It was the first form of life. 
B)  It oxygenated the atmosphere. 
C)  It fertilized the soil to let plants grow. 
D)  It increased the carbon dioxide in the atmosphere, causing the greenhouse effect. 
E)  It was the first life form based on DNA. 
A)  It was the first form of life. 
B)  It oxygenated the atmosphere. 
C)  It fertilized the soil to let plants grow. 
D)  It increased the carbon dioxide in the atmosphere, causing the greenhouse effect. 
E)  It was the first life form based on DNA.

Question 9

What is the major difference between prokaryotes and eukaryotes?

Accepted Answer

A)  Eukaryotes have DNA, and prokaryotes have RNA. 
B)  Eukaryotes have a nuclear membrane surrounding their DNA, and prokaryotes do not. 
C)  Eukaryotes are planets, and prokaryotes are animals. 
D)  Eukaryotes appeared on Earth before prokaryotes. 
E)  Eukaryotes are single-celled, and prokaryotes are multicellular. 
A)  Eukaryotes have DNA, and prokaryotes have RNA. 
B)  Eukaryotes have a nuclear membrane surrounding their DNA, and prokaryotes do not. 
C)  Eukaryotes are planets, and prokaryotes are animals. 
D)  Eukaryotes appeared on Earth before prokaryotes. 
E)  Eukaryotes are single-celled, and prokaryotes are multicellular.

Question 10

What are the four main elements that make up all living organisms on the Earth?

Accepted Answer

CHON: carb

Question 11

If we model the history of the universe as a single day, at what time would the first primitive forms of single-celled microorganisms appear?

Accepted Answer

A)  5:00 A.M. 
B)  9:00 A.M. 
C)  12:00 noon 
D)  3:00 P.M. 
E)  5:20 P.M. 
A)  5:00 A.M. 
B)  9:00 A.M. 
C)  12:00 noon 
D)  3:00 P.M. 
E)  5:20 P.M.

Question 12

If we wanted to search the Milky Way for other civilizations, where should we look?

Accepted Answer

A)  near high-mass stars, because they live longer 
B)  near low-mass stars, because their habitable zones are farther from their stars 
C)  near the galactic center, because the higher temperature makes life more likely 
D)  in the disk of the Milky Way, because planets there are more protected from harmful gamma rays and X-rays coming from the galactic center 
E)  in the halo of the Milky Way, because stars in the halo have more heavy elements than stars in the disk 
A)  near high-mass stars, because they live longer 
B)  near low-mass stars, because their habitable zones are farther from their stars 
C)  near the galactic center, because the higher temperature makes life more likely 
D)  in the disk of the Milky Way, because planets there are more protected from harmful gamma rays and X-rays coming from the galactic center 
E)  in the halo of the Milky Way, because stars in the halo have more heavy elements than stars in the disk

Question 13

Which of these pictures depicts the situation with the lowest entropy?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 14

Why could life not have existed on land any earlier than 475 million years ago?

Accepted Answer

A)  The temperature was too high. 
B)  There was too little sunlight. 
C)  There was too little oxygen in the atmosphere. 
D)  Earth was covered in erupting volcanoes. 
E)  There was no land because Earth was covered in water. 
A)  The temperature was too high. 
B)  There was too little sunlight. 
C)  There was too little oxygen in the atmosphere. 
D)  Earth was covered in erupting volcanoes. 
E)  There was no land because Earth was covered in water.

Question 15

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 44,000 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 taking much longer for their 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 taking much longer for their response to make it back to Earth.

Question 16

Why was a comet impact 65 million years ago a chance happening that benefited the evolution of humans?

Accepted Answer

A)  It deposited a significant amount of nitrogen into the Earth's atmosphere. 
B)  It led to an increase in global UV radiation, which killed off most of the forests and jungles. 
C)  Mammals got an evolutionary boost. 
D)  Plant life began to decline. 
E)  It brought human DNA to Earth. 
A)  It deposited a significant amount of nitrogen into the Earth's atmosphere. 
B)  It led to an increase in global UV radiation, which killed off most of the forests and jungles. 
C)  Mammals got an evolutionary boost. 
D)  Plant life began to decline. 
E)  It brought human DNA to Earth.

Question 17

The ability for one generation to pass on its characteristics to future generations is known as:

Accepted Answer

A)  natural selection 
B)  mutations 
C)  heredity 
D)  self-replication 
E)  duplication 
A)  natural selection 
B)  mutations 
C)  heredity 
D)  self-replication 
E)  duplication

Question 18

Approximately 10 percent of all life on Earth has been in the form of microorganisms.

Accepted Answer

A) True 
 B)False

Question 19

Which of the following elements are NOT found in DNA molecules?

Accepted Answer

A)  carbon 
B)  nitrogen 
C)  hydrogen 
D)  helium 
E)  oxygen 
A)  carbon 
B)  nitrogen 
C)  hydrogen 
D)  helium 
E)  oxygen

Question 20

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

Accepted Answer

SETI is the Search for Extraterrestrial

Exam 24: Life

The second law of thermodynamics states that:

SETI's Allen Telescope Array is designed to search ___________ for signs of intelligent life.

The main goal of the Allen Telescope Array is to search for high redshift galaxies.

Carbon forms the backbone of our DNA primarily because:

If the most pessimistic assumptions in the Drake equation were true, we would:

People argue against the possibility of time travel by saying, "If humans will eventually be able to travel back in time, then where are all the tourists from the future?" This idea is similar to the ___________, only applied to time travel instead of aliens.

Which of the following is a likely source of the energy needed to create the first life on Earth?

Why did the presence of cyanobacteria on Earth in the past allow humans to exist?

What is the major difference between prokaryotes and eukaryotes?

What are the four main elements that make up all living organisms on the Earth?

If we model the history of the universe as a single day, at what time would the first primitive forms of single-celled microorganisms appear?

If we wanted to search the Milky Way for other civilizations, where should we look?

Which of these pictures depicts the situation with the lowest entropy?

Why could life not have existed on land any earlier than 475 million years ago?

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 44,000 years. Why?

Why was a comet impact 65 million years ago a chance happening that benefited the evolution of humans?

The ability for one generation to pass on its characteristics to future generations is known as:

Approximately 10 percent of all life on Earth has been in the form of microorganisms.

Which of the following elements are NOT found in DNA molecules?

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

Why Learn Astronomy

Patterns in the Skymotions of Earth

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Birth and Evolution of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquid the Giant Planets

Planetary Adornmentsmoons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Our Starthe Sun

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

The Expanding Universe

Galaxies

The Milky Waya Normal Spiral Galaxy

Modern Cosmology

Large-Scale Structure in the Universe

Filters