Deck 23: Life

Question 1

Terrestrial life is composed of 20 different acids that are composed of only 4 different chemical elements.

Answer 1

True

Question 2

Where do we think life first formed on the Earth?

A) In the air
B) In the oceans
C) On land
D) On asteroids that carried microorganisms to Earth

Answer 2

In the oceans

Question 3

The four main chemicals of which life on Earth are composed are hydrogen,carbon,oxygen,and sulfur.

Answer 3

False

Question 4

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

A) Bacteria
B) Eukarya
C) Archaea
D) Fungi

Question 5

Why was the comet impact a chance happening that benefited the evolution of humans?

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.

Question 6

If we model the age of the universe as a single day,at what time would the earliest traces of humanity appear on the Earth?

A) 11:00:00 P.M.
B) 11:35:00 P.M.
C) 11:53:10 P.M.
D) 11:59:25 P.M.

Question 7

According to the theory of evolution,chemical reactions resulting in the mutation of a molecule are a natural and inevitable occurrence.

Question 8

What occurred approximately 500 million years ago?

A) The extinction of the dinosaurs
B) The Cambrian explosion
C) The rise of mammals
D) The birth of the first humans

Question 9

In 1952,chemists Harold Urey and Stanley Miller mixed ammonia,methane,and hydrogen in a closed container,zapped it with electrical sparks and found that

A) they could induce cold fusion to occur.
B) they could not induce any amino acids to form.
C) single-celled microorganisms had been spontaneously created.
D) they had created about half the amino acids contained in DNA.

Question 10

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

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

Question 11

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

A) algae.
B) bacteria.
C) eukaryotes.
D) prokaryotes.

Question 12

The Drake equation estimates the number of solar systems in our galaxy today that may harbor life.

Question 13

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

Question 14

Some forms of life on Earth are silicon-based.

Question 15

If we model the history of the Earth as a single day,at what time would the first human civilizations appear?

A) 0.2 seconds before midnight
B) 2 minutes before midnight
C) 10:00 P.M.
D) 6:00 P.M.

Question 16

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 has intelligent life?

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

Question 17

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

Question 18

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

Question 19

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

Question 20

The habitable zone for a star ranges from 0.9 to 1.4 AU from the star.

Question 21

A value of for the Drake equation signifies that

A) 1 out of every 10 solar systems in our galaxy harbors intelligent life.
B) 1 out of every 10 solar systems in our galaxy harbors life of some kind.
C) 1 out of every 10 galaxies in our universe harbors intelligent life.
D) 1 out of every 10 galaxies in our universe harbors life of some kind.

Question 22

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

Question 23

Calculate the maximum likelihood that any technically advanced civilization that arose still exists in our galaxy today.

Question 24

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

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

Question 25

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

Question 26

Which one of the following is NOT one of the six chemical elements commonly found in living organisms?

A) helium
B) hydrogen
C) phosphorus
D) nitrogen

Question 27

The second law of thermodynamics states that

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.

Question 28

What would be the number of intelligent civilizations in our galaxy if all stars formed planets,each planet has a 0.1 percent change of supporting life,and every time conditions are right life develops,but only 0.001 percent of the time intelligent life develops,and once it develops it survives indefinitely?

Question 29

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

Question 30

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

A) have to wait for approximately 60 million years
To get a message back from the nearest intelligent life.
B) have to wait for approximately 400 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.

Question 31

Name three main dangers (one human and two astrophysical)that threaten the continued existence of human life on Earth.

Question 32

The habitable zone around a star depends most on its

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

Question 33

If a mutation occurred and spawned a population B that had a 25 percent higher chance of reproducing than the original population A,in how many generations would B make up 90 percent of the total population?

A) 8
B) 16
C) 20
D) 24

Question 34

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

Question 35

If the entire history of the Earth 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?

Question 36

Carbon forms the backbone of our DNA because

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.

Question 37

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 48,000 years.Why not?

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.

Question 38

We search for intelligent life in the universe by

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) All of the above

Question 39

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

Question 40

If you wanted to find intelligent life in the universe,what spectral types of stars would you study and why?