Question 1

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 2

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 3

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

Accepted Answer

Mutations can be either good o

Question 4

The image below is of an Australian shoreline.Which of the following forms of early life on Earth does it depict?

Accepted Answer

A) stromatolites 
B) cyanobacteria 
C) eukaryotes 
D) meteorites 
E) fungi 
A) stromatolites 
B) cyanobacteria 
C) eukaryotes 
D) meteorites 
E) fungi

Question 5

In which of the following locations has life NOT been found on Earth?

Accepted Answer

A) near deep-oceans hydrothermal vents 
B) in extremely dry deserts 
C) in Arctic ice 
D) in hot sulfur springs 
E) None of the above.Life has been found in all of these locations. 
A) near deep-oceans hydrothermal vents 
B) in extremely dry deserts 
C) in Arctic ice 
D) in hot sulfur springs 
E) None of the above.Life has been found in all of these locations.

Question 6

What was the goal of the experiment depicted below?

Accepted Answer

A) to create a microorganism 
B) to simulate the formation of Earth 
C) to simulate the Big Bang 
D) to simulate the early universe 
E) to simulate the formation of the building blocks of life 
A) to create a microorganism 
B) to simulate the formation of Earth 
C) to simulate the Big Bang 
D) to simulate the early universe 
E) to simulate the formation of the building blocks of life

Question 7

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 8

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 9

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 10

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 11

Some forms of life on Earth are silicon-based.

Accepted Answer

A) True 
 B)False

Question 12

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

Accepted Answer

A) True 
 B)False

Question 13

Which of the following Solar System objects is NOT a good candidate for future searches for life?

Accepted Answer

A) Mars,because it once had liquid water on the surface 
B) Jupiter's moon Europa,because it appears to have liquid water under its frozen surface 
C) Saturn's moon Titan,because it has an atmosphere containing many organic molecules 
D) Pluto,because a large portion of it is made of water ice 
E) Saturn's moon Enceladus,because its cryovolcanoes indicate that it has liquid water under the surface 
A) Mars,because it once had liquid water on the surface 
B) Jupiter's moon Europa,because it appears to have liquid water under its frozen surface 
C) Saturn's moon Titan,because it has an atmosphere containing many organic molecules 
D) Pluto,because a large portion of it is made of water ice 
E) Saturn's moon Enceladus,because its cryovolcanoes indicate that it has liquid water under the surface

Question 14

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?

Accepted Answer

A) 10 
B) 16 
C) 20 
D) 24 
E) 32 
A) 10 
B) 16 
C) 20 
D) 24 
E) 32

Question 15

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 16

When the Pioneer and Voyager spacecraft were launched into space in the 1970s,they were outfitted with messages describing where they came from.Why is it fairly unlikely that an alien civilization will use them to find us?

Accepted Answer

A) The extremely large distances between stars means it will take a very long time before they reach another solar system. 
B) They will probably rust and fall apart as they get older. 
C) They will burn up as the Sun's gravity pulls them in. 
D) They will likely run into Kuiper Belt objects before they leave the Solar System. 
E) They are moving so fast through space that they would be very difficult to catch. 
A) The extremely large distances between stars means it will take a very long time before they reach another solar system. 
B) They will probably rust and fall apart as they get older. 
C) They will burn up as the Sun's gravity pulls them in. 
D) They will likely run into Kuiper Belt objects before they leave the Solar System. 
E) They are moving so fast through space that they would be very difficult to catch.

Question 17

A value of N = 0.1 for the Drake equation signifies that:

Accepted Answer

A) one out of every 10 solar systems in our galaxy harbors intelligent life 
B) one out of every 10 solar systems in our galaxy harbors life of some kind 
C) one out of every 10 galaxies in our universe harbors intelligent life 
D) one out of every 10 galaxies in our universe harbors life of some kind 
E) approximately one intelligent civilization in the universe is created every 10 billion years. 
A) one out of every 10 solar systems in our galaxy harbors intelligent life 
B) one out of every 10 solar systems in our galaxy harbors life of some kind 
C) one out of every 10 galaxies in our universe harbors intelligent life 
D) one out of every 10 galaxies in our universe harbors life of some kind 
E) approximately one intelligent civilization in the universe is created every 10 billion years.

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

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

Accepted Answer

A) True 
 B)False

Question 20

The habitable zone around a star depends most on its:

Accepted Answer

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

Exam 24: Life

Carbon forms the backbone of our DNA primarily because:

What is the major difference between prokaryotes and eukaryotes?

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

The image below is of an Australian shoreline.Which of the following forms of early life on Earth does it depict?

In which of the following locations has life NOT been found on Earth?

What was the goal of the experiment depicted below?

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

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

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?

Some forms of life on Earth are silicon-based.

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

Which of the following Solar System objects is NOT a good candidate for future searches for life?

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?

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

When the Pioneer and Voyager spacecraft were launched into space in the 1970s,they were outfitted with messages describing where they came from.Why is it fairly unlikely that an alien civilization will use them to find us?

A value of N = 0.1 for the Drake equation signifies that:

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

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

The habitable zone around a star depends most on its:

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 Adornments Moons 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