Transcript Midterm review

© 2011 Pearson Education, Inc.
01.01 What is the difference between a sea and an ocean? (Ch. 1,
Section “How Many Oceans Exist on Earth?”)
A.
B.
C.
D.
E.
Seas are smaller in area
Seas are shallower in average depth
Seas are partly enclosed by land
Seas have a salinity that is different from the main oceans
All of the above
© 2011 Pearson Education, Inc.
01.01 What is the difference between a sea and an ocean? (Ch. 1,
Section “How Many Oceans Exist on Earth?”)
A.
B.
C.
D.
E.
Seas are smaller in area
Seas are shallower in average depth
Seas are partly enclosed by land
Seas have a salinity that is different from the main oceans
All of the above
Correct answer: E. All of these answers are correct statements
about the difference between a sea and an ocean.
© 2011 Pearson Education, Inc.
01.02 What invention made accurate open ocean navigation
possible by determining longitude? (Ch. 1, Fig. 1D, Box 1.2
“How do Sailors Know Where They Are at Sea?”)
A.
B.
C.
D.
E.
Alidade
Sextant
Chronometer
Orrery
Magnetic compass
© 2011 Pearson Education, Inc.
01.02 What invention made accurate open ocean navigation
possible by determining longitude? (Ch. 1, Fig. 1D, Box 1.2
“How do Sailors Know Where They Are at Sea?”)
A.
B.
C.
D.
E.
Alidade
Sextant
Chronometer
Orrery
Magnetic compass
Correct answer: C. John Harrison’s chronometer
allowed longitude to be accurately calculated (for the
time) which made it possible to reliably map islands
and distant coasts. The other items are all navigation
instruments, but not the correct answer to the
question.
© 2011 Pearson Education, Inc.
01.03 What is a scientific theory? (Ch. 1, Section “Theories and the
Truth”)
A. A proven fact
B. An explanation for a natural phenomenon that is supported
by many observations
C. The same thing as a hypothesis
D. An explanation for a natural phenomenon that has the
approval of scientific leaders
E. An explanation for a natural phenomenon that is thought by
most people to be true
© 2011 Pearson Education, Inc.
01.03 What is a scientific theory? (Ch. 1, Section “Theories and the
Truth”)
A. A proven fact
B. An explanation for a natural phenomenon that is
supported by many observations
C. The same thing as a hypothesis
D. An explanation for a natural phenomenon that has the
approval of scientific leaders
E. An explanation for a natural phenomenon that is thought by
most people to be true
Correct answer: B. A and C are incorrect. D and E are
common fallacies.
© 2011 Pearson Education, Inc.
01.04 Why does the Earth have a nickel-iron core at its center,
surrounded by silicate mantle? (Ch. 1, Section “Density and
Density Stratification”)
A. The core formed first from metallic meteorites
B. The intense pressure at the center of the Earth caused
primordial nebular material to transmutate into metal
C. A metal core occurs at the center of most planets
D. Because it is more massive, the core material sank to the
center of the Earth
E. Silicates are less rigid than metal, so the mantle and crust
flowed outward to the exterior
© 2011 Pearson Education, Inc.
01.04 Why does the Earth have a nickel-iron core at its center,
surrounded by silicate mantle? (Ch. 1, Section “Density and
Density Stratification”)
A. The core formed first from metallic meteorites
B. The intense pressure at the center of the Earth caused
primordial nebular material to transmutate into metal
C. A metal core occurs at the center of most planets
D. Because it is more massive, the core material sank to
the center of the Earth
E. Silicates are less rigid than metal, so the mantle and crust
flowed outward to the exterior
Correct answer: D. Not long after the initial accretion of the Earth as a
planet, the interior melted and this allowed denser materials (i.e., the
metals) to sink to the center while lighter silicates formed a shell around
them. A is incorrect because metallic meteorites are thought to have formed
in a planetary interior and are not therefore precursors. B is nonsense. C is
correct but not an answer to the question. E is incorrect because the rigidity
was not at issue.
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01.05 Why is continental crust higher than ocean crust? (Ch. 1,
Section "Density and Density Stratification"
A. Continental crust is higher because it has more material
beneath it
B. Ocean crust has to cover 70% of the Earth’s surface, so it
is spread out and therefore thinner
C. Continental crust is less massive and higher because it is
hotter than ocean crust
D. The granite-type rock that makes up much of continental
crust naturally forms mountains
E. Continental crust is thicker and less dense than ocean
crust, so it floats higher on the mantle
© 2011 Pearson Education, Inc.
01.05 Why is continental crust higher than ocean crust? (Ch. 1,
Section "Density and Density Stratification"
A. Continental crust is higher because it has more material
beneath it
B. Ocean crust has to cover 70% of the Earth’s surface, so it
is spread out and therefore thinner
C. Continental crust is less massive and higher because it is
hotter than ocean crust
D. The granite-type rock that makes up much of continental
crust naturally forms mountains
E. Continental crust is thicker and less dense than
ocean crust, so it floats higher on the mantle
Correct answer: E. A is incorrect because the crust has no
more material beneath it (when considered in terms of
mass) because of isostatic balance. C is incorrect because
continental crust is actually cooler. B and D are nonsense.
© 2011 Pearson Education, Inc.
01.06 According to the Nebular Hypothesis, the Sun, Earth, and
other planets in our solar system formed from an enormous
cloud of gas and dust. Which of the following is not true
about the Earth shortly after its formation? (Ch. 1, Section
“How Were Earth and the Solar System Created?”)
A. There were no oceans
B. Metals had not yet coalesced in the Earth’s center
to form the core
C. The atmosphere was composed mostly of oxygen
D. The surface was bombarded by meteorites
E. There was not yet a Moon
© 2011 Pearson Education, Inc.
01.06 According to the Nebular Hypothesis, the Sun, Earth, and
other planets in our solar system formed from an enormous
cloud of gas and dust. Which of the following is not true
about the Earth shortly after its formation? (Ch. 1, Section
“How Were Earth and the Solar System Created?”)
A. There were no oceans
B. Metals had not yet coalesced in the Earth’s center
to form the core
C. The atmosphere was composed mostly of
oxygen
D. The surface was bombarded by meteorites
E. There was not yet a Moon
Correct answer: C. If the Earth had an atmosphere shortly
after accretion, it probably did not have significant free
oxygen. Oxygen would not be significant until about
2 billion years later. Answers A, B, D, and E are all true
statements and can be used to reinforce the idea that
primitive Earth was vastly different from its present state.
© 2011 Pearson Education, Inc.
01.07 Continental and ocean crust have different levels because
oceanic crust is denser and “floats” lower on the
asthenosphere than continental crust because of isostasy.
Assuming no difference in structure, what would happen if
the two types of crust were made of the same material?
(Ch. 1, Section 1.4, Section “Earth’s Internal Structure”)
A. The height difference would remain the same
B. There would still be a difference because continental crust is
thicker than ocean crust, but the heights would be nearly the
same
C. Continental crust is thicker, so the height difference would
increase
D. Isostasy would no longer apply since both types would have
the same mass
E. Because the oceanic crust is thinner, it would float higher
© 2011 Pearson Education, Inc.
01.07 Continental and ocean crust have different levels because
oceanic crust is denser and “floats” lower on the
asthenosphere than continental crust because of isostasy.
Assuming no difference in structure, what would happen if
the two types of crust were made of the same material?
(Ch. 1, Section 1.4, Section “Earth’s Internal Structure”)
A. The height difference would remain the same
B. There would still be a difference because continental
crust is thicker than ocean crust, but the heights would
be more nearly the same
C. Continental crust is thicker, so the height difference would
increase
D. Isostasy would no longer apply since both types would have
the same mass
E. Because the oceanic crust is thinner, it would float higher
Correct answer: B. The crust would still be lighter than
asthenosphere, so thicker crust would be higher, although less
so because the density difference would be removed. Answers
A, C, D, and E are incorrect statements.
© 2011 Pearson Education, Inc.
01.08 Charles Darwin considered a career as a minister. What
would have happened to the theory of evolution had he not
become a scientist instead? (Ch. 1, Box 1.3 “The Voyage of
HMS Beagle”)
A. The theory of evolution would not exist
B. Somebody else would have proposed the same idea at
about the same time
C. Somebody else would have proposed the same idea,
but probably not until much later
D. The theory of evolution would be much different than it
is today
E. He would have still published the theory of evolution
anyway
© 2011 Pearson Education, Inc.
01.08 Charles Darwin considered a career as a minister. What
would have happened to the theory of evolution had he not
become a scientist instead? (Ch. 1, Box 1. 3 “The Voyage of
HMS Beagle”)
A.
B.
C.
D.
E.
The theory of evolution would not exist
Somebody else would have proposed the same idea at
about the same time
Somebody else would have proposed the same idea, but
probably not until much later
The theory of evolution would be much different than it is
today
He would have still published the theory of evolution anyway
Correct answer: B. Often great ideas are “in the air”. Alfred Wallace published research with
nearly the same idea at the same time as Darwin published “On the Origin of Species.” Some
historians think the coincidence occurred because Darwin held his ideas until he was afraid of
being “scooped.” Answer A assumes that only Darwin could have come up with the idea.
Answer C probably gives Darwin too much credit for being ahead of his time. Answer D
assumes that theories have differences that are personality related, which misunderstands
the scientific process. Answer E seems unlikely if Darwin did not make his Beagle
observations and was distracted by other duties. In counterpoint, Einstein came up with his
the theory of relativity while working as a patent clerk.
© 2011 Pearson Education, Inc.
01.09 A rock sample has 6 billion K40 atoms (parent isotope), and
6 billion Ar40 atoms (daughter isotope). After two half lives,
what is the content of the rock sample? (Ch. 1, Section
“Radiometric Age Dating”)
A.
B.
C.
D.
E.
9 billion K40 atoms and 3 billion Ar40 atoms
1.5 billion K40 atoms and 10.5 billion Ar40 atoms
0 K40 atoms and 12 billion Ar40 atoms
.75 billion K40 atoms and 11.25 billion Ar40 atoms
3 billion K40 atoms and 9 billion Ar40 atoms
© 2011 Pearson Education, Inc.
01.09 A rock sample has 6 billion K40 atoms (parent isotope), and
6 billion Ar40 atoms (daughter isotope). After two half lives,
what is the content of the rock sample? (Ch. 1, Section
“Radiometric Age Dating”)
A.
B.
C.
D.
E.
9 billion K40 atoms and 3 billion Ar40 atoms
1.5 billion K40 atoms and 10.5 billion Ar40 atoms
0 K40 atoms and 12 billion Ar40 atoms
.75 billion K40 atoms and 11.25 billion Ar40 atoms
3 billion K40 atoms and 9 billion Ar40 atoms
Correct answer: E. One half life has already passed, given the
stable daughter product. The second half life involves halving the
6 billion, which would equal 3 billion.
© 2011 Pearson Education, Inc.
01.10 Which of the following would isostatic adjustment apply to?
(Ch. 1, Section “Earth’s Internal Structure”)
A. The floating of the lithosphere upon denser
mantle beneath
B. The adjustment of species’ behavior/structures
(adaptations) to new environments
C. The adjustment of the amounts of CO2 released
during photosynthesis
D. The formation of our solar system
© 2011 Pearson Education, Inc.
01.10 Which of the following would isostatic adjustment apply to?
(Ch. 1, Section “Earth’s Internal Structure”)
A. The floating of the lithosphere upon denser
mantle beneath
B. The adjustment of species’ behavior/structures
(adaptations) to new environments
C. The adjustment of the amounts of CO2 released
during photosynthesis
D. The formation of our solar system
Correct answer: A. Isostacy refers to the buoyancy of a lithospheric
plate on top of the asthenosphere. The other answers are incorrect.
© 2011 Pearson Education, Inc.
01.11 Which of the following is NOT true about the oxygen on
Earth? (Ch. 1, Section “The Importance of Oxygen to Life”)
A.
B.
C.
D.
E.
It shields the Earth from ultraviolet radiation
It is necessary for respiration for many organisms
It is essential for anaerobic bacteria’s survival
It is a byproduct of photosynthesis
When oxygen concentrations are high, speciation
occurs rapidly
© 2011 Pearson Education, Inc.
01.11 Which of the following is NOT true about the oxygen on
Earth? (Ch. 1, Section “The Importance of Oxygen to Life”)
A.
B.
C.
D.
E.
It shields the Earth from ultraviolet radiation
It is necessary for respiration for many organisms
It is essential for anaerobic bacteria’s survival
It is a byproduct of photosynthesis
When oxygen concentrations are high, speciation
occurs rapidly
Correct answer: C. Oxygen was not present in Earth’s troposhphere
when anaerobic bacteria (by definition, without oxygen) evolved.
The other answers are all correct statements.
© 2011 Pearson Education, Inc.
05.01 Many of the unique properties of water, such as cohesion
and its reputation as a universal solvent, come from its
atomic structure. What causes these properties? (Ch. 5,
Section “The Water Molecule”)
A. Atoms in water molecules are stuck together with atomic
bonds
B. Atoms in water molecules are stuck together with covalent
bonds
C. Water molecules are electrically polarized
D. Water molecules contain sodium (Na) ions that break down
substances
E. Many other ions can substitute for the hydrogen (H) atoms in
a water molecule
© 2011 Pearson Education, Inc.
05.01 Many of the unique properties of water, such as cohesion
and its reputation as a universal solvent, come from its
atomic structure. What causes these properties? (Ch. 5,
Section “The Water Molecule”)
A.
B.
C.
D.
Atoms in water molecules are stuck together with atomic bonds
Atoms in water molecules are stuck together with covalent bonds
Water molecules are electrically polarized
Water molecules contain sodium (Na) ions that break down
substances
E. Many other ions can substitute for the hydrogen (H) atoms in a
water molecule
Correct answer: C. The electrical polarization causes water
molecules to stick together with hydrogen bonds. This gives them
cohesion. The polarization also allows water to break down
substances whose molecules are glued by ionic bonds by attracting
the constituent ions. Answer A is nonsense; B is correct, but not the
answer. Answers D and E are nonsense.
© 2011 Pearson Education, Inc.
05.02 What is the unit that is equivalent to raising the temperature
of 1 gram of water by 1 degree centigrade? (Ch. 5, Section
“Water’s Thermal Properties”)
A.
B.
C.
D.
E.
Calorie
Van der Waals
Heat capacity
Kilocalorie
Joule
© 2011 Pearson Education, Inc.
05.02 What is the unit that is equivalent to raising the temperature
of 1 gram of water by 1 degree centigrade? (Ch. 5, Section
“Water’s Thermal Properties”)
A.
B.
C.
D.
E.
Calorie
Van der Waals
Heat capacity
Kilocalorie
Joule
Correct answer: A. The definition of a calorie is “the amount
Of energy required to raise the temperature of 1 gram of water by
1 degree centigrade, the other answers are not correct.
© 2011 Pearson Education, Inc.
05.03 Why does ocean temperature change little from day to night?
(Ch. 5, Section “Water’s Thermal Properties”)
A. Marine ice caps keep ocean water from heating up too much
B. Lesser cloudiness over the oceans allows them to soak up
more solar energy than land
C. Salts in ocean water absorb sunlight during the day and
release it at night
D. Stronger, more consistent winds over the ocean distribute
heat evenly
E. High heat capacity absorbs solar energy quickly and
releases it slowly
© 2011 Pearson Education, Inc.
05.03 Why does ocean temperature change little from day to night?
(Ch. 5, Section “Water’s Thermal Properties”)
A. Marine ice caps keep ocean water from heating up too much
B. Lesser cloudiness over the oceans allows them to soak up
more solar energy than land
C. Salts in ocean water absorb sunlight during the day and
release it at night
D. Stronger, more consistent winds over the ocean distribute
heat evenly
E. High heat capacity absorbs solar energy quickly and
releases it slowly
Correct answer: E. Water is capable of storing a tremendous
amount of heat and is a conductor of energy. Air is an
insulator and does not make for the effective transfer of
energy A–D are incorrect statements.
© 2011 Pearson Education, Inc.
05.04 What does the principle of constant proportions tell us?
(Ch. 5, Section “Determining Salinity”)
A. No matter where ocean salinity is measured, the result is the
constant
B. No matter the salinity of ocean water, the ratios of major
dissolved ions remains the same
C. The amount of chloride ions (Cl-) in ocean water is constant
D. Remove a major dissolved salt from ocean water and other
salts increase to keep the salinity constant
E. Ocean water salts are dissolved ions
© 2011 Pearson Education, Inc.
05.04 What does the principle of constant proportions tell us?
(Ch. 5, Section “Determining Salinity”)
A. No matter where ocean salinity is measured, the result is the
constant
B. No matter the salinity of ocean water, the ratios of major
dissolved ions remains the same
C. The amount of chloride ions (Cl-) in ocean water is constant
D. Remove a major dissolved salt from ocean water and other
salts increase to keep the salinity constant
E. Ocean water salts are dissolved ions
Correct answer: B. Answers A, C, and D are incorrect
statements. Answer E is a correct statement but not the
answer to the question.
© 2011 Pearson Education, Inc.
05.05 Which of the following processes is NOT part of the
hydrologic cycle? (Ch. 5, Section “Dissolved Components
Added to and Removed from Seawater”)
A. Water soaks into the soil to form groundwater
B. Water is locked up in ice in polar caps
C. Water flows from rivers to the oceans
D. Water is added to the oceans and atmosphere by volcanic
activity
E. Water is evaporated from the oceans to form water vapor and
clouds
© 2011 Pearson Education, Inc.
05.05 Which of the following processes is NOT part of the
hydrologic cycle? (Ch. 5, Section “Dissolved Components
Added to and Removed from Seawater”)
A.
B.
C.
D.
Water soaks into the soil to form groundwater
Water is locked up in ice in polar caps
Water flows from rivers to the oceans
Water is added to the oceans and atmosphere by volcanic
activity
E. Water is evaporated from the oceans to form water vapor and
clouds
Correct answer: D. The hydrologic cycle concept has water moving from one
reservoir to another. The addition of new water to the system is therefore not
part of the cycle because it cannot cycle back to that reservoir. A sharp
student could point out that water could recycle to volcanoes. How? Water
subducted in sediments and ocean crust at convergent plate boundaries is
released into the upper mantle and eventually makes its way to island arc
volcanoes through magma ascent. This is a slow process and tiny compared
to other parts of the hydrologic cycle, so it is usually not included. Answers A,
B, C, and E are all parts of the cycle.
© 2011 Pearson Education, Inc.
05.06 How does the latent heat of evaporation (and its equivalent,
the latent heat of condensation) moderate climate? (Ch. 5,
Section “Why Does Water Have Such Unusual Chemical
Properties?”)
A. It retards the formation of ice, keeping the oceans warmer
B. By absorbing energy on evaporation and releasing it on
condensation, it keeps water cool when the air is hot and warm
when the air is cool
C. The endothermic reaction does not allow salt to build up past a
certain concentration
D. The latent heat helps generate winds, which help keep the oceans
cool when the air is hot
E. It gives water a higher heat capacity, which allows it to stay cool
when the air is warm and warm when the air is cool
© 2011 Pearson Education, Inc.
05.06 How does the latent heat of evaporation (and its equivalent,
the latent heat of condensation) moderate climate? (Ch. 5,
Section “Why Does Water Have Such Unusual Chemical
Properties?”)
A. It retards the formation of ice, keeping the oceans warmer
B. By absorbing energy on evaporation and releasing it on
condensation, it keeps water cool when the air is hot and
warm when the air is cool
C. The endothermic reaction does not allow salt to build up past a
certain concentration
D. The latent heat helps generate winds, which help keep the oceans
cool when the air is hot
E. It gives water a higher heat capacity, which allows it to stay cool
when the air is warm and warm when the air is cool
Correct answer: B. The two latent heats tend to work against
temperature swings. Answers A, C, and D are incorrect statements.
Answer E is almost correct, but it is the molecular properties that
determine the heat capacity, not the latent heat itself.
© 2011 Pearson Education, Inc.
05.07 Hydrothermal vents are considered both a source and sink
for ocean salts. How can one factor both add and take away
salt? (Ch. 5, Section “Dissolved Components Added to and
Removed from Seawater”)
A. As water interacts with hot rock, some materials are
dissolved whereas others are deposited
B. Due to random variations in chemical reactions, salts are
both deposited and dissolved in the vents
C. The dissolved material cycles round and round in the vents,
first being precipitated and then dissolved, then repeating
again and again
D. Hot vents give off material first as gas, which precipitates
salt, only to be dissolved by fluids moving through the vent
plumbing
E. The statement is incorrect. Hydrothermal vents are only a
source for salts, not a sink
© 2011 Pearson Education, Inc.
Hydrothermal vents are considered both a source and sink
for ocean salts. How can one factor both add and take away
salt? (Ch. 5, Section “Dissolved Components Added to and
Removed from Seawater”)
As water interacts with hot rock, some materials are dissolved
whereas others are deposited
Due to random variations in chemical reactions, salts are both
deposited and dissolved in the vents
The dissolved material cycles round and round in the vents, first
being precipitated and then dissolved, then repeating again and
again
Hot vents give off material first as gas, which precipitates salt, only
to be dissolved by fluids moving through the vent plumbing
The statement is incorrect. Hydrothermal vents are only a source
for salts, not a sink
05.07
A.
B.
C.
D.
E.
Correct answer: A. the hotter a fluid is, the more readily it is able to
dissolve a rock, and when the water temperature cools,
precipitation occurs. Answers B–E are incorrect statements.
© 2011 Pearson Education, Inc.
05.08 In the oceans, all of the following processes decrease local
salinity except for one. Which process increases salinity?
(Ch. 5, Sections: “Processes Affecting Seawater Salinity,”
and “Dissolved Components Added to and Removed from
Seawater”)
A.
B.
C.
D.
E.
Precipitation
River runoff
Evaporation
Sea ice melting
Icebergs melting
© 2011 Pearson Education, Inc.
05.08 In the oceans, all of the following processes decrease local
salinity except for one. Which process increases salinity?
(Ch. 5, Sections: “Processes Affecting Seawater Salinity,”
and “Dissolved Components Added to and Removed from
Seawater”)
A.
B.
C.
D.
E.
Precipitation
River runoff
Evaporation
Sea ice melting
Icebergs melting
Correct answer: C. Evaporation increases local salinity by
removing water from the ocean and leaving salts behind.
The other answers (A, B, D, and E) are all processes that
add water to the ocean without adding salt, thereby
decreasing local salinity.
© 2011 Pearson Education, Inc.
05.09 How does water have such strong surface tension? (Ch. 5,
Section “The Water Molecule”)
A. Water molecules are constantly bumping against each other,
creating strong surface tension
B. Water is the universal solvent, and so has extremely strong
surface tension
C. Hydrogen bonds form between adjacent molecules due to
water’s polarity, thus giving it strong surface tension
D. Water has high kinetic energy, resulting in strong surface
tension
© 2011 Pearson Education, Inc.
05.09 How does water have such strong surface tension? (Ch. 5,
Section “The Water Molecule”)
A. Water molecules are constantly bumping against each other,
creating strong surface tension
B. Water is the universal solvent, and so has extremely strong
surface tension
C. Hydrogen bonds form between adjacent molecules due
to water’s polarity, thus giving it strong surface tension
D. Water has high kinetic energy, resulting in strong surface
tension
Correct answer: C. The oxygen side of a water molecule
sticks to the hydrogen side of another water molecule,
holding the mass together. Answers A and B are correct
statements; however, they do not answer the question.
© 2011 Pearson Education, Inc.
05.10 Why are lakes like the Dead Sea and Great Salt Lake so
buoyant? (Ch. 5, Section “Salinity Variations”)
A. The water is brackish; it has a high amount of dissolved
solids, making it extremely dense and buoyant
B. The water is hypersaline; it has a high amount of dissolved
solids, making it extremely dense and buoyant
C. Salt water meets freshwater at these lakes, making them
extremely buoyant
D. None of the above
© 2011 Pearson Education, Inc.
05.10 Why are lakes like the Dead Sea and Great Salt Lake so
buoyant? (Ch. 5, Section “Salinity Variations”)
A. The water is brackish; it has a high amount of dissolved
solids, making it extremely dense and buoyant
B. The water is hypersaline; it has a high amount of
dissolved solids, making it extremely dense and buoyant
C. Salt water meets freshwater at these lakes, making them
extremely buoyant
D. None of the above
Correct answer: B. Evaporation has occurred at a rapid
pace, which causes pure water to leave the water bodies,
and leaves behind the salts that were weathered from
terrestrial rocks. The other statements are false—the saltier
the water, the more buoyant the water will be.
© 2011 Pearson Education, Inc.
05.11 Water in the ocean combines with carbon dioxide to form a
weak acid called carbonic acid. But the ocean’s pH is 8.1 on
average, which is slightly basic. How is this so? (Ch. 5,
Section “The Carbonate Buffering System”)
A.
B.
C.
D.
Water has a set pH and never fluctuates
Because of ocean water’s salt content, it is always basic
A and B
There is a natural buffer system
© 2011 Pearson Education, Inc.
05.11 Water in the ocean combines with carbon dioxide to form a
weak acid called carbonic acid. But the ocean’s pH is 8.1 on
average, which is slightly basic. How is this so? (Ch. 5,
Section “The Carbonate Buffering System”)
A.
B.
C.
D.
Water has a set pH and never fluctuates
Because of ocean water’s salt content, it is always basic
A and B
There is a natural buffer system
Correct answer: D. The carbonate rocks in the ocean are
able to absorb the carbonic acid and keep the pH of the
seawater at 8.1. The other answers are incorrect.
© 2011 Pearson Education, Inc.
12.01 Plankton are organisms that float. Why is a copepod, which
can swim and propel itself through the water, classified as
plankton? (Ch. 12, Section “Plankton”)
A. It lives at the surface of the ocean where plankton live
B. It was classified as a plankton before it was known that
copepods are swimmers
C. It has a swim bladder that keeps it from sinking, so it is a
floater
D. It spends part of its life floating and part swimming, so it is
classified as plankton because of the floating part
E. Because of its small size, it cannot swim very fast or very far,
so its location is determined by currents
© 2011 Pearson Education, Inc.
12.01 Plankton are organisms that float. Why is a copepod, which
can swim and propel itself through the water, classified as
plankton? (Ch. 12, Section “Plankton”)
A. It lives at the surface of the ocean where plankton live
B. It was classified as a plankton before it was known that
copepods are swimmers
C. It has a swim bladder that keeps it from sinking, so it is a
floater
D. It spends part of its life floating and part swimming, so it is
classified as plankton because of the floating part
E. Because of its small size, it cannot swim very fast or
very far, so its location is determined by currents
Correct answer: E. There is a common misconception that an
organism that can swim must therefore be a nekton, but the
deciding factor is whether the organism can swim well enough
to move significant distances through the water, irrespective of
currents.
© 2011 Pearson Education, Inc.
12.02 Of Earth’s total number of species, why are the fewest in the
marine pelagic realm? (Ch. 12, Section “How Many Marine
Species Exist?”)
A. There is more area on land for different species
B. Uniform conditions in the pelagic realm make fewer
specialized environments for organism adaptation as
different species
C. Organisms need a hard substrate (either land or sea bottom)
in order to evolve into different species
D. Evolution of differing species is triggered by extinction, but
extinction is rare in the pelagic environment
E. The pelagic realm contains the photic zone, and solar
radiation in the photic zone suppresses the number of new
species that evolve
© 2011 Pearson Education, Inc.
12.02 Of Earth’s total number of species, why are the fewest in the
marine pelagic realm? (Ch. 12, Section “How Many Marine
Species Exist?”)
A. There is more area on land for different species
B. Uniform conditions in the pelagic realm make fewer
specialized environments for organism adaptation as
different species
C. Organisms need a hard substrate (either land or sea bottom)
in order to evolve into different species
D. Evolution of differing species is triggered by extinction, but
extinction is rare in the pelagic environment
E. The pelagic realm contains the photic zone, and solar
radiation in the photic zone suppresses the number of new
species that evolve
Correct answer: B. The dark, cold, nutrient-poor pelagic zone is
not biodiverse. Answers C. D. and E. are incorrect statements.
© 2011 Pearson Education, Inc.
12.03 Why do most fish and marine mammals have the same
torpedo-like, streamlined shape? (Ch. 12, Section “Water’s
Viscosity”)
A. A streamlined shape presents a greater surface area to
volume ratio, which allows easier regulation of internal heat
B. If you are going to move through a substance, like water, it is
necessary to have a head and eyes at one end and a tail at
the other
C. Streamlining looks better to the opposite sex, so it leads to
greater reproduction
D. The streamlined shape minimizes energy expended to move
through the water
E. They can swim faster with streamlined shapes
© 2011 Pearson Education, Inc.
12.03 Why do most fish and marine mammals have the same
torpedo-like, streamlined shape? (Ch. 12, Section “Water’s
Viscosity”)
A. A streamlined shape presents a greater surface area to volume
ratio, which allows easier regulation of internal heat
B. If you are going to move through a substance, like water, it is
necessary to have a head and eyes at one end and a tail at the
other
C. Streamlining looks better to the opposite sex, so it leads to greater
reproduction
D. The streamlined shape minimizes energy expended to move
through the water
E. They can swim faster with streamlined shapes
Correct answer: D. Water is more viscous than air, so all aquatic
nekton have to be designed to move efficiently through this viscous
substance. Swimming faster (Answer E) is partly correct, but not the
most basic answer because not all fish rely on being fast swimmers,
but almost all have streamlined shapes.
© 2011 Pearson Education, Inc.
12.04 Most fresh water fish are hypertonic, meaning their body
cells contain more salt than the surrounding water. Since
osmosis should push water into their cells, why don’t they
explode? (Ch. 12, Section “Salinity”)
A. They urinate a lot, so the water does not build up
B. They don’t drink any water, since they get so much from
osmosis
C. Their cells have adapted to absorb salt
D. They have adapted to live with high osmotic pressure
E. All of the above
© 2011 Pearson Education, Inc.
12.04 Most fresh water fish are hypertonic, meaning their body
cells contain more salt than the surrounding water. Since
osmosis should push water into their cells, why don’t they
explode? (Ch. 12, Section “Salinity”)
A. They urinate a lot, so the water does not build up
B. They don’t drink any water, since they get so much from
osmosis
C. Their cells have adapted to absorb salt
D. They have adapted to live with high osmotic pressure
E. All of the above
Correct answer: E. All of the above are true statements.
© 2011 Pearson Education, Inc.
12.05 What is the primary difference between pelagic environment
zones below the photic zone? (Ch. 12, Section “What Are
Living Things, and How Are They Classified?”)
A.
B.
C.
D.
E.
Increasing pressure with increasing depth
Decreasing oxygen with increasing depth
Decreasing light with increasing depth
Increase in salinity with decreasing temperature
Decreasing food abundance with increasing depth
© 2011 Pearson Education, Inc.
12.05 What is the primary difference between pelagic environment
zones below the photic zone? (Ch. 12, Section “What Are
Living Things, and How Are They Classified?”)
A.
B.
C.
D.
E.
Increasing pressure with increasing depth
Decreasing oxygen with increasing depth
Decreasing light with increasing depth
Increase in salinity with decreasing temperature
Decreasing food abundance with increasing depth
Correct answer: A. Light (Answer B) is almost absent in the
Mesopelagic zone and absent in the Bathypelagic and
Abyssalpelagic zones. The salinity, temperature, food
abundance, and oxygen content do not vary much (Answers
B, D, and E). The pressure change is the greatest variable.
© 2011 Pearson Education, Inc.
12.06 Why don’t fish (right) have spines like the foraminifera (left)
to keep them from sinking? (Ch. 12, Section “How are
Marine Organizations Adapted for the Physical Conditions of
the Ocean?”)
A. The drag would use up too much energy in swimming
B. The fish is too heavy, so the drag would not slow its sinking
by much
C. The drag would hinder the fish from catching prey
D. None of the above
E. Answers A, B, and C
© 2011 Pearson Education, Inc.
12.06 Why don’t fish (right) have spines like the foraminifera (left) to keep
them from sinking? (Ch. 12, Section “How are Marine
Organizations Adapted for the Physical Conditions of the Ocean?”)
A. The drag would use up too much energy in swimming
B. The fish is too heavy, so the drag would not slow its sinking by
much
C. The drag would hinder the fish from catching prey
D. None of the above
E. Answers A, B, and C
Correct answer: D. The drag from the spines would use up much of
the fish’s energy and slow it down so it couldn’t easily catch prey.
Besides, the drag wouldn’t help the fish much because it is much
heavier and larger than a foraminifera.
© 2011 Pearson Education, Inc.
12.07 Which of the following organisms is in the same kingdom as
humans (kingdom: animalia)? (Ch. 12, Section “What Are
Living Things, and How are They Classified?”)
A.
B.
C.
D.
E.
Giant kelp
Blue-green algae
Eel grass
Bat star
Bacteria
© 2011 Pearson Education, Inc.
12.07 Which of the following organisms is in the same kingdom as
humans (kingdom: animalia)? (Ch. 12, Section “What Are
Living Things, and How are They Classified?”)
A.
B.
C.
D.
E.
Giant kelp
Blue-green algae
Eel grass
Bat star
Bacteria
Correct answer: D. The bat star is also in kingdom animalia.
The giant kelp (Answer A) is in kingdom protoctista. The bluegreen algae (Answer B) is in kingdom monera. The eel grass
(Answer C) is in kingdom plantae. The bacteria (Answer E) is
also in kingdom monera.
© 2011 Pearson Education, Inc.
12.08 Which of the following is an incorrect statement about the
marine environment? (Ch. 12, Section “What Are the Main
Divisions of the Marine Environment?”)
A. Pressure is generally greater than on land
B. Free oxygen is more abundant than the terrestrial
environment
C. Temperatures are more stable than on land
D. Salinity is an issue in the ocean but not on land
E. Because of the viscosity difference between water and air, it
is much easier for organisms to move through the air
© 2011 Pearson Education, Inc.
12.08 Which of the following is an incorrect statement about the
marine environment? (Ch. 12, Section “What Are the Main
Divisions of the Marine Environment?”)
A. Pressure is generally greater than on land
B. Free oxygen is more abundant than the terrestrial
environment
C. Temperatures are more stable than on land
D. Salinity is an issue in the ocean but not on land
E. Because of the viscosity difference between water and air, it
is much easier for organisms to move through the air
Correct answer: B. All of the statements above correctly reflect
differences between land and ocean environments except for
Answer B. Free oxygen is not abundant in the oceans and
most oxygen is dissolved.
© 2011 Pearson Education, Inc.
12.09 Which of the following is the most specific way to group
organisms according to the current taxonomic classification
system? (Ch. 12, Section “What Are Living Things, and How
Are They Classified?”)
A.
B.
C.
D.
E.
Genus
Phylum
Species
Order
Family
© 2011 Pearson Education, Inc.
12.09 Which of the following is the most specific way to group
organisms according to the current taxonomic classification
system? (Ch. 12, Section “What Are Living Things, and How
Are They Classified?”)
A.
B.
C.
D.
E.
Genus
Phylum
Species
Order
Family
Correct answer: C. The most specific label one can give an
organism is to refer to it by its species names. Answers A, B,
D, and E are higher-order taxonomic classifications and refer
to groups of species with similar traits.
© 2011 Pearson Education, Inc.
12.10 What marine organism represents the vast majority of the
ocean’s biomass? (Ch. 12, Section “How Are Marine
Organisms Classified?”)
A.
B.
C.
D.
E.
Plankton
Sea cucumbers
Shrimp
Fish
Crustaceans
© 2011 Pearson Education, Inc.
12.10 What marine organism represents the vast majority of the
ocean’s biomass? (Ch. 12, Section “How Are Marine
Organisms Classified?”)
A.
B.
C.
D.
E.
Plankton
Sea cucumbers
Shrimp
Fish
Crustaceans
Correct answer: A. Plankton dominate the ocean in terms of
biomass. Answers B–E are common organisms, but in no
way rival the biomass of plankton.
© 2011 Pearson Education, Inc.
12.11 What is a probable reason why land species represent 86%
of the world’s species, whereas marine species only
represent 14%? (Ch. 12, Section “How Many Marine Species
Exist?”)
A. There is more land on Earth than there is ocean
B. Water slows down the evolutionary process
C. The more variable the environment, the more chances
there will be for new species to form and the ocean is
more stable than the land environment
D. An underwater cataclysmic event during the Pleistocene
killed many marine species which reduced the previously
abundant marine species count to less than the number
of land species
© 2011 Pearson Education, Inc.
12.11 What is a probable reason why land species represent 86%
of the world’s species, whereas marine species only
represent 14%? (Ch. 12, Section “How Many Marine Species
Exist?”)
A. There is more land on Earth than there is ocean
B. Water slows down the evolutionary process
C. The more variable the environment, the more
chances there will be for new species to form and the
ocean is more stable than the land environment
D. An underwater cataclysmic event during the Pleistocene
killed many marine species which reduced the previously
abundant marine species count to less than the number
of land species
Correct answer: C. The ocean being a stable, relatively
unchanging environment means it makes sense that land species
represent 86% of the world’s species, and marine species only
represent 14%. Answers A, B, and D are incorrect statements.
© 2011 Pearson Education, Inc.
13.01 Biological oceanographers discuss about biomass frequently.
Just what is biomass? (Ch. 13, Section “What is Primary
Productivity?”)
A.
B.
C.
D.
E.
The amount of organisms produced in a given time
The total weight of protoplasm contained in a given organism
The total mass of all organisms of a given class
The total number of organisms within a given class
The total number of organisms within a given class divided
by the total weight of those organisms
© 2011 Pearson Education, Inc.
13.01 Biological oceanographers discuss about biomass frequently.
Just what is biomass? (Ch. 13, Section “What is Primary
Productivity?”)
A.
B.
C.
D.
E.
The amount of organisms produced in a given time
The total weight of protoplasm contained in a given organism
The total mass of all organisms of a given class
The total number of organisms within a given class
The total number of organisms within a given class divided
by the total weight of those organisms
Correct answer: C. Biomass is the total mass of all
organisms of a given class. Answers A. B. D. and E. are
not the definitions of biomass.
© 2011 Pearson Education, Inc.
13.02 What is the difference between gross primary productivity and net
primary productivity? (Ch. 13, Section “What Kind of Photosynthetic
Marine Organisms Exist?”)
A. Net productivity is the amount of organic material from
photosynthesizers that can be caught in a net
B. Gross productivity is the amount of organic carbon created by
photosynthesis per unit of time and net productivity is the gross minus
the amount of organic carbon consumed by the photosynthesizers
C. Gross productivity is the total amount of organic carbon produced
during a day, but net productivity is the amount left over after
predation by grazing organisms
D. Gross productivity is the amount of organic matter created in a unit
time and net productivity is the amount that is recycled
E. Gross productivity is the amount of energy that is created by
photosynthesizers and net productivity is the energy passed on to
grazing organisms
© 2011 Pearson Education, Inc.
13.02 What is the difference between gross primary productivity and net
primary productivity? (Ch. 13, Section “What Kind of Photosynthetic
Marine Organisms Exist?”)
A. Net productivity is the amount of organic material from
photosynthesizers that can be caught in a net
B. Gross productivity is the amount of organic carbon created by
photosynthesis per unit of time and net productivity is the gross minus
the amount of organic carbon consumed by the photosynthesizers
C. Gross productivity is the total amount of organic carbon produced during a
day, but net productivity is the amount left over after predation by grazing
organisms
D. Gross productivity is the amount of organic matter created in a unit time and
net productivity is the amount that is recycled
E. Gross productivity is the amount of energy that is created by
photosynthesizers and net productivity is the energy passed on to grazing
organisms
Correct answer: B. Some of the other answers sound right or
contain partly true statements, but the key factors are total organic
carbon created minus the organic carbon used. Answer D sounds
right, but it defines that part that is reused, not the net.
© 2011 Pearson Education, Inc.
13.03 What are the two primary factors that control biologic
productivity in the surface oceans? (Ch. 13, Section “Factors
Affecting Primary Productivity”)
A.
B.
C.
D.
E.
Sunlight and temperature
Temperature and sunlight
Temperature and nutrients
Sunlight and nutrients
Sunlight and oxygen
© 2011 Pearson Education, Inc.
13.03 What are the two primary factors that control biologic
productivity in the surface oceans? (Ch. 13, Section “Factors
Affecting Primary Productivity”)
A.
B.
C.
D.
E.
Sunlight and temperature
Temperature and sunlight
Temperature and nutrients
Sunlight and nutrients
Sunlight and oxygen
Correct answer: D. the two primary factors that control
biologic productivity in the surface oceans are sunlight and
nutrients. Though A. B. C. and E., temperature, nutrients,
and oxygen do control biological productivity at the surface
of the oceans, these are minor factors relative to sunlight
and nutrients.
© 2011 Pearson Education, Inc.
13.04 What is the biological pump? (Ch. 13, Section “How Does
Regional Productivity Vary?”)
A. Osmosis pushes nutrients across cell membranes, allowing
the nutrients to get from the bloodstream to where they are
needed by the cells
B. Photosynthetic organisms take in carbon dioxide and give off
oxygen
C. Photosynthetic organisms use sunlight, carbon dioxide, and
water to create energy
D. The removal of nitrogen from the water by biologic
productivity
E. The removal of organic matter and nutrients from surface
water to deep water through the sinking of dead surfacedwelling organisms
© 2011 Pearson Education, Inc.
13.04 What is the biological pump? (Ch. 13, Section “How Does
Regional Productivity Vary?”)
A. Osmosis pushes nutrients across cell membranes, allowing
the nutrients to get from the bloodstream to where they are
needed by the cells
B. Photosynthetic organisms take in carbon dioxide and give off
oxygen
C. Photosynthetic organisms use sunlight, carbon dioxide, and
water to create energy
D. The removal of nitrogen from the water by biologic
productivity
E. The removal of organic matter and nutrients from
surface water to deep water through the sinking of dead
surface-dwelling organisms
Correct answer: E. The biological pump involves the removal of organic
matter and nutrients from surface water to deep water through the sinking of
dead surface-dwelling organisms. Although statements B. C. and D. are
correct, they do not pertain to the biological pump, and statement A. is false.
© 2011 Pearson Education, Inc.
13.05 Why is upwelling such an important factor in creating areas
of high biologic productivity? (Ch. 13, Section “How Does
Regional Productivity Vary?”)
A. Upwelling brings nutrient-rich deep water to the surface
where productivity is limited by the availability of nutrients
B. Upwelling delivers oxygen-rich water to the surface where
productivity is limited by oxygen content in the water
C. Upwelling brings cool deep waters to the surface where
productivity is limited by high temperature
D. Upwelling brings new phytoplankton to the surface where
they can multiply rapidly
E. Upwelling causes rain, which results in less salty surface
waters that are better suited for primary productivity
© 2011 Pearson Education, Inc.
13.05 Why is upwelling such an important factor in creating areas
of high biologic productivity? (Ch. 13, Section “How Does
Regional Productivity Vary?”)
A. Upwelling brings nutrient-rich deep water to the surface
where productivity is limited by the availability of
nutrients
B. Upwelling delivers oxygen-rich water to the surface where
productivity is limited by oxygen content in the water
C. Upwelling brings cool deep waters to the surface where
productivity is limited by high temperature
D. Upwelling brings new phytoplankton to the surface where
they can multiply rapidly
E. Upwelling causes rain, which results in less salty surface
waters that are better suited for primary productivity
Correct answer: A. Upwelling brings nutrient-rich deep water to the
surface where productivity is limited by the availability of nutrients.
Statements B. C. D. and E. are incorrect stataements regarding
coastal biological productivity.
© 2011 Pearson Education, Inc.
13.06 Why are sessile, plant-like macroalgae (i.e., those attached
to the ocean bottom) only found in littoral and sub-littoral
environments? (Ch. 13, Sections 13.2, Section “Macroscopic
(Large) Algae”)
A. They need rocks for attachment and rocks are not found in the
deep-sea
B. They need nutrients that are found only in the littoral and sublittoral zones
C. They cannot survive in clear waters offshore because of
excessive solar ultraviolet radiation
D. They require light to reach the ocean bottom, which only
occurs in these two zones
E. They need to live in an area where wave energy reaches to the
seafloor, which only occurs in these two environments
© 2011 Pearson Education, Inc.
13.06 Why are sessile, plant-like macroalgae (i.e., those attached
to the ocean bottom) only found in littoral and sub-littoral
environments? (Ch. 13, Sections 13.2, Section “Macroscopic
(Large) Algae”)
A. They need rocks for attachment and rocks are not found in the
deep-sea
B. They need nutrients that are found only in the littoral and sublittoral zones
C. They cannot survive in clear waters offshore because of
excessive solar ultraviolet radiation
D. They require light to reach the ocean bottom, which only
occurs in these two zones
E. They need to live in an area where wave energy reaches to the
seafloor, which only occurs in these two environments
Correct answer: D. The light is the controlling factor. The
other answers are incorrect statements.
© 2011 Pearson Education, Inc.
13.07 Given what you know about surface productivity, where do
you think that sunlight penetrates deepest into the ocean?
(Ch. 13, Figure 13.6)
A.
B.
C.
D.
E.
North Atlantic
Circum-Antarctic
Middle gyre
Equator
Near continental margins
© 2011 Pearson Education, Inc.
13.07 Given what you know about surface productivity, where do
you think that sunlight penetrates deepest into the ocean?
(Ch. 13, Figure 13.6)
A.
B.
C.
D.
E.
North Atlantic
Circum-Antarctic
Middle gyre
Equator
Near continental margins
Correct answer: C. Light will penetrate farthest where there
are least particles in the water, which means the surface
productivity is low. This occurs in the middle gyre areas
(Answer C). Productivity is higher in the North Atlantic
(Answer A), Circum-Antarctic (Answer B), equatorial
(Answer D), and continental margin (Answer E) zones.
© 2011 Pearson Education, Inc.
13.08 Why are plankton greater in biomass than nekton and
benthos? (Ch. 13, Section “Transfer Efficiency”)
A. Plankton are eaten by both nekton and benthos and only 10%
of the energy is transmitted across tropic levels
B. Because plankton are small, they utilize nutrients more
efficiently
C. Benthos and nekton do not reproduce as quickly
D. Phytoplankton use solar energy to create new biomass and
this is more efficient than other mechanisms
E. The statement is incorrect. Nekton and benthos together have
greater biomass than plankton.
© 2011 Pearson Education, Inc.
13.08 Why are plankton greater in biomass than nekton and
benthos? (Ch. 13, Section “Transfer Efficiency”)
A. Plankton are eaten by both nekton and benthos and only 10%
of the energy is transmitted across tropic levels
B. Because plankton are small, they utilize nutrients more
efficiently
C. Benthos and nekton do not reproduce as quickly
D. Phytoplankton use solar energy to create new biomass and
this is more efficient than other mechanisms
E. The statement is incorrect. Nekton and benthos together have
greater biomass than plankton.
Correct answer: B. Because plankton are the food source for most nekton
and benthos (ultimately, through detritus) and the transfer efficiency of
energy is only 10%, there must be much greater biomass in plankton.
Answers A, D, and E are incorrect statements. Answer C is mostly true,
but does not address the question.
© 2011 Pearson Education, Inc.
13.09 In photosynthesis, what two things must come together with
light energy input to produce sugar and oxygen? (Ch. 13,
Section “What Is Primary Productivity?”)
A.
B.
C.
D.
E.
Hydrogen and carbon dioxide
Water and oxygen
Hydrothermal vents and oxygen
Water and hydrogen
Water and carbon dioxide
© 2011 Pearson Education, Inc.
13.09 In photosynthesis, what two things must come together with
light energy input to produce sugar and oxygen? (Ch. 13,
Section “What Is Primary Productivity?”)
A.
B.
C.
D.
E.
Hydrogen and carbon dioxide
Water and oxygen
Hydrothermal vents and oxygen
Water and hydrogen
Water and carbon dioxide
Correct answer: E. Water and carbon dioxide are used to produce
sugar and oxygen during photosynthesis. Answers A–D are
incorrect statements.
© 2011 Pearson Education, Inc.
13.10 What influences ocean color? (Ch. 13, Section “Light
Transmission in Ocean Water”)
A. The level of turbidity as a result of runoff
B. The level of photosynthetic pigment which has a positive
correlation with biological production
C. The level of salinity
D. Both A and B
E. None of the above
© 2011 Pearson Education, Inc.
13.10 What influences ocean color? (Ch. 13, Section “Light
Transmission in Ocean Water”)
A. The level of turbidity as a result of runoff
B. The level of photosynthetic pigment which has a positive
correlation with biological production
C. The level of salinity
D. Both A and B
E. None of the above
Correct answer: D. Ocean color is influenced by turbidity from runoff
and the photosynthetic pigments in the water. Salinity does not
influence color.
© 2011 Pearson Education, Inc.
13.11 What is responsible for the red tide phenomenon? (Ch. 13,
Section “Microscopic (Small) Algae”)
A. The water appears red as a result of reduced levels of
photosynthetic pigment
B. It’s a phenomenon that usually coincides with storm surges;
the name comes from the red kelp that often washes ashore
as a result of rough weather
C. Red tide occurs in patches of water where certain species of
dinoflagellates flourish. They are so abundant that the water
becomes discolored and takes on a red hue.
D. Red tides occur once a year and in accordance with the lunar
cycle
© 2011 Pearson Education, Inc.
13.11 What is responsible for the red tide phenomenon? (Ch. 13,
Section “Microscopic (Small) Algae”)
A. The water appears red as a result of reduced levels of
photosynthetic pigment
B. It’s a phenomenon that usually coincides with storm surges;
the name comes from the red kelp that often washes ashore
as a result of rough weather
C. Red tide occurs in patches of water where certain species
of dinoflagellates flourish. They are so abundant that the
water becomes discolored and takes on a red hue.
D. Red tides occur once a year and in accordance with the lunar
cycle
Correct answer: C. Red tide is a natural phenomenon which occurs
in patches of water where certain species of dinoflagellates flourish.
Answers A, B, and D are incorrect.
© 2011 Pearson Education, Inc.