Deck 14: Ocean Water and Ocean Life

Question 1

Between 25° and 35° latitude, salinity is likely to be _______ .

A) high
B) average
C) seasonally variable
D) low

Answer 1

high

Question 2

Deep ocean temperatures are_______ at low latitudes compared to high latitudes.

A) lower
B) very constant
C) highly variable
D) higher
E) about the same

Answer 2

about the same

Question 3

The average salinity of seawater is_______ .

A) 30.0%
B) 0.01%
C) 0.27%
D) 3.5%
E) 19.8%

Answer 3

3.5%

Question 4

At high latitudes the thermocline is _______ .

A) wider than at low latitudes
B) narrower than at low latitudes
C) about the same as at low latitudes
D) There is no thermocline at high latitudes.
E) There is no thermocline at low latitudes.

Question 5

Thermoclines in the ocean are best developed at _______ .

A) lower latitudes
B) higher latitudes
C) regions close to continents
D) both high and low latitudes

Question 6

Seawater has become more acidic since the industrial revolution and this is commonly attributed to_______ .

A) global climate change, which is changing the temperature of seawater and producing a related change in the water chemistry
B) human dumping of large quantities of waste materials into the oceans that increase the acid content of the water
C) the increase in CO₂ being put into the atmosphere and then absorbed into the oceans
D) a decrease in the amount of base compounds to neutralize the natural acids in seawater
E) the loss of calcite- secreting organisms and reef- builders in the oceans due to pollution

Question 7

The most abundant salt in seawater is_______ _.

A) SiO₂
B) NaCl
C) KCl
D) MgCl₂

Question 8

The Atlantic Ocean has lower salinity than other oceans because _______ .

A) it has more rainfall and runoff and less evaporation than other oceans
B) it spans all of the latitudes
C) it has less rainfall and runoff and more evaporation than other oceans
D) it is getting larger, and this increases the area where salt can flow into the ocean
E) it is getting smaller and this decrease the surface area for salt to evaporate

Question 9

The proportion of dissolved substances in seawater is expressed as 0/00, which is the same as_______ .

A) parts per million
B) parts per billion
C) parts per thousand
D) parts per hundred

Question 10

Salinity in the ocean is highest in regions where_______ is high and_______ is low.

A) precipitation; evaporation
B) precipitation; temperature
C) evaporation; precipitation
D) temperature; evaporation

Question 11

The thermocline is important because _______ .

A) the ability for the ocean to dissolve CO₂ from the atmosphere is dependent on temperature over a range of depths.
B) different chemical compositions form at different temperatures
C) it controls the climate and rate of evaporation and precipitation near the oceans
D) it forms a barrier to many types of marine life that can only exist within certain temperature ranges
E) none of the above

Question 12

In tropical regions the surface temperature of the oceans is high but decreases rapidly with depth between 300 and 1000 meters because _______ .

A) sunlight cannot penetrate much below the surface of the oceans
B) rapidly upwelling cold currents occur in these regions
C) volcanic activity on the seafloor is rare in the tropics
D) cold water from the polar regions flows just below the surface
E) tropical regions are areas of high rainfall and this rapidly lowers the temperature of seawater

Question 13

Scientists infer that chemical weathering of crustal rocks is not the only source of some minerals, such as chlorine, bromine, sulfur, and boron because _______ .

A) there are more of those minerals in the oceans than can be derived from crustal rocks alone
B) the minerals are highly reactive and are not found as compounds that would come from crustal material
C) those minerals have the wrong isotopic composition for weathering products of crustal rocks
D) some of the minerals are only found in meteorites and must have an extraterrestrial source
E) none of the above

Question 14

Consider the below chart of Arctic Sea ice in September of each year: What is causing the loss of sea ice?

A) volcanism
B) biolotical activity
C) global warming
D) changes in surface salinity

Question 15

The surface mixed zone is characterized by_______ .

A) high density water near the surface that rapidly decreases in density with depth
B) nearly constant temperatures to a depth of about 300 meters
C) a rapid change from warm temperatures on top to cold temperatures at a depth of about 300 meters
D) a mixture of temperatures and densities to a depth of about 300 to 450 meters depth
E) low density water near the surface that rapidly increases in density with depth

Question 16

Which of the following is not a process that removes dissolved components from seawater?

A) chemical precipitation
B) organisms building hard parts
C) hydrothermal activity
D) evaporation
E) All of the above remove components from seawater.

Question 17

Density is an important property of ocean water because_______ .

A) it determines the vertical position of the water
B) it determines the chemistry of the water
C) it determines the temperature of the water
D) it determines the horizontal position of the water
E) it only changes when there is a major change in water chemistry

Question 18

The dissolved materials in seawater are thought to originate from chemical weathering of rocks on the continents and also from_______ _.

A) organisms
B) evaporation of fresh water
C) meteorites
D) erosion
E) outgassing of elements from Earth's interior

Question 19

The total amount of solid material dissolved in water is known as_______ .

A) load
B) insoluble residue
C) solute
D) salinity

Question 20

What happens when fresh water flows into seawater?

A) The sea water covers the fresh water.
B) There is a continuous gradation from fresh water on top to sea water on the bottom.
C) They mix completely.
D) The fresh water covers the sea water.
E) There is a continuous gradation from seawater on top to fresh water on the bottom.

Question 21

Hydrothermal vents provide a unique deep sea environment that supports abundant life because _______ .

A) food carried in the hydrothermal fluids provides a hospitable environment to support abundant life
B) the hydrothermal vents support photosynthesis so there is abundant food
C) the density of the seawater is less and this allows organisms more mobility
D) the heat from the hydrothermal vents provides a more hospitable environment to support life

Question 22

Density in seawater is determined by_______ .

A) salinity
B) temperature
C) both temperature and salinity
D) none of these

Question 23

Productivity is the amount of carbon fixed by organisms through the synthesis of organic matter using energy derived from_______ and _______ .

A) photosynthesis; hydrothermal
B) hydrothermal; available nutrients
C) chemosynthesis; photosynthesis
D) chemosynthesis; hydrothermal
E) none of these

Question 24

Most marine animals live near the surface of the ocean because of _______ , which supports photosynthesis by marine algae that form the basis of the food chain.

A) air
B) sunlight
C) warmer temperatures
D) thermocline

Question 25

Why is productivity low in tropical regions?

A) because the low density of the water makes it hard for plankton to float near the surface
B) because there is too much sunlight
C) because the deep waters are too warm to maintain a healthy biomass
D) because the thermocline acts as a barrier to the mixing of surface and deep waters
E) All of the above are problems.

Question 26

Productivity of diatoms is highest in _______ .

A) fall
B) spring
C) summer
D) winter

Question 27

Organisms, such as algae and bacteria, that drift with ocean currents are known as_______ .

A) nekton
B) benthos organisms
C) biomass
D) plankton
E) none of these

Question 28

Fish most commonly live_______ .

A) in the upper part of the oceans
B) near islands and continents
C) far from islands and continents
D) in the deepest parts of the ocean
E) in the thermoclines

Question 29

Seaweed large marine algae. grows in shallow coastal regions because _______ .

A) there is more sunlight reaching the seafloor in those regions
B) they feed on the organisms washed into the ocean from nearby land
C) the surf is an important part of their mobility
D) they require fresh water to reproduce

Question 30

What limits productivity in polar regions?

A) the lack of sunlight year round
B) The thermocline acts as a barrier to mixing of surface and deep waters.
C) high density of the surface waters
D) low temperatures of the surface waters
E) all of the above

Question 31

One disadvantage to living near the surface of the ocean is_______ .

A) waves create difficulty in finding abundant food
B) too many other marine organisms live near the surface so competition for food is difficult
C) strong currents bring rapid changes to the environment
D) maneuvering in the water can be difficult and make it a problem to avoid predators

Question 32

On the deep seafloor, organisms are widely distributed _______ .

A) to avoid predators
B) because they have eaten most of their near neighbors
C) because there is little variation in substrate and no photosynthesis
D) because it is too cold to move and reproduction is slow

Question 33

Productivity is highest in _______ .

A) polar oceans
B) temperate oceans
C) tropical oceans
D) none of the above

Question 34

Consider the below image of a bather easily floating in the Dead Sea, exerting no effort to do so. Why is it so easy for the sunbather to stay afloat?

A) The thermocline is right near the surface and the temperature differential near her helps her to float.
B) The low water density in this region helps buoyancy.
C) The high biological activity produces gases to buoy her.
D) The high salinity in that body of water buoys her.

Question 35

Animals capable of moving independent of the ocean currents, by swimming or other means of propulsion, are called _______ .

A) plankton
B) benthos organisms
C) biomass
D) nekton

Question 36

_______ organisms live on or in the ocean bottom.

A) Scavenging
B) Benthonic
C) Planktonic
D) Nektonic
E) none of these

Question 37

The deep zone is characterized by_______ .

A) water that gradually decreases in temperature and increases in density with depth
B) water with relatively uniform temperature and density throughout
C) water that gradually decreases in temperature and density with depth
D) water that gradually increases in temperature and density with depth
E) water that gradually increases in temperature and decreases in density with depth

Question 38

Productivity in temperate oceans is determined by _______ .

A) seasons
B) latitude
C) ocean currents
D) all of these

Question 39

The portion of the ocean where photosynthesis can occur is called the_______ zone.

A) nektic
B) benthic
C) euphotic
D) neritic

Question 40

Major fisheries are concentrated in the neritic zone above the continental shelf. because of all of the following except _______ .

A) nutrients wash in from land
B) there is an abundance of sunlight to support photosynthesis
C) the sea bottom provides shelter and habitat
D) there are rapid changes in oxygen concentrations, temperature, and salinity that encourage diversity

Question 41

Examine the words and/or phrases below and determine the relationship among the majority of words/phrases. Choose the option that does not fit the pattern.

A) plankton
B) neritic
C) benthos
D) nekton

Question 42

In the food chain, each feeding stage is called a _______ level.

A) bios
B) trophic
C) replenishment
D) none of these

Question 43

The upper part of the ocean into which sunlight penetrates is called the_______ .

A) intertidal zone
B) oceanic zone
C) neritic zone
D) photic zone

Question 44

Salinity refers to _______ .

A) ocean thermal gradient
B) amount of sea life
C) salt content
D) all solid dissolved minerals

Question 45

_______ is the most important factor in the process of photosynthesis.

A) Salinity
B) Sunlight
C) Temperature
D) Pressure

Question 46

The reason that fishers choose a population that feeds close to the primary producing population is that_______ .

A) they will be close to shore so it is easier to fish those regions
B) energy transfer between trophic levels is inefficient and this will increase the available biomass
C) there will be a bigger variety of food available in those locations because there will be several trophic levels available
D) it is easier to recover more biomass from the fish because they have not wasted energy swimming after food
E) none of the above

Question 47

Thermoclines in the ocean are best developed at _______ latitudes.

A) higher
B) polar
C) lower
D) middle

Question 48

Seawater contains _______ of the natural occurring elements on earth.

A) about half
B) a few
C) most
D) all

Question 49

The open ocean, regardless of depth, where animals swim or float freely is called the_______ zone.

A) pelagic zone
B) oceanic zone
C) intertidal zone
D) photic zone

Question 50

Feeding stages in the food chain are known as _______ levels.

A) pelagic
B) photic
C) trophic
D) epipelagic

Question 51

_______ is the most abundant salt found in seawater.

A) Sodium chloride
B) Calcium sulfate
C) Thorium
D) Borate

Question 52

The density of seawater is controlled by_______ .

A) temperature
B) salinity
C) neither temperature nor salinity
D) both temperature and salinity

Question 53

Productivity in the oceans is highest in_______ regions.

A) equatorial
B) middle latitude
C) polar
D) aphotic

Question 54

Organisms that feed through a food web instead of a food chain are more likely to survive because_______ .

A) there is more biomass in a food web than in a food chain
B) if a member of the food web diminishes in availability, there are still many other things to eat
C) the variety of food in a web is healthier so the organisms are more likely to live a long time
D) food webs may contain organisms from different trophic levels

Question 55

Clams, sponges, and other bottom- dwelling animals are called _______ .

A) Scavenging organisms
B) Planktonic organisms
C) Nektonic organisms
D) Benthos organisms

Question 56

Examine the words and/or phrases below and determine the relationship among the majority of words/phrases. Choose the option that does not fit the pattern.

A) sodium chloride
B) carbon dioxide
C) magnesium chloride
D) sodium sulfate

Question 57

_______ are organisms that swim freely in the ocean.

A) Benthos organisms
B) Scavenging organisms
C) Nektonic organisms
D) Planktonic organisms

Question 58

The_______ is where the land and ocean meet and overlap.

A) intertidal zone
B) neritic zone
C) photic zone
D) oceanic zone

Question 59

Examine the words and/or phrases below and determine the relationship among the majority of words/phrases. Choose the option that does not fit the pattern.

A) oceanic zone
B) neritic zone
C) photic zone
D) intertidal zone

Question 60

Productivity of zooplankton is highest in _______ .

A) summer
B) winter
C) fall
D) spring

Question 61

_______ refers to the mass of all living organisms on Earth.

A) Food web
B) Biomass
C) Benthos
D) Trophic level

Question 62

The largest influence on density in oceans is _______ .

A) tectonic activity
B) temperature
C) salinity
D) biomass

Question 63

Among plankton, animals that drift on ocean currents are specifically known as _______ .

A) phytoplankton
B) neuroplankton
C) primary plankton
D) zooplankton

Question 64

Discuss variations in temperature and density of seawater with depth in the oceans. Please use Figure 14.3 to help with your discussion. What are the key factors that influence or control temperature and density? Are these variations the same worldwide or are they specific to certain regions? Explain.

Question 65

Large Blue whales that are up to 30 meters long live primarily on _______ that is/are only about 6 cm long.

A) lobsters
B) fish
C) krill
D) squid

Question 66

Marine organisms are influenced by a variety of physical oceanographic factors including_______ .

A) water depth
B) availability of sunlight
C) distance from shore
D) all of these

Question 67

_______ refers to the change in temperature with depth in the ocean.

A) Pycnocline
B) Halocline
C) Thermocline
D) Cryocline

Question 68

The_______ zone refers to the area where the land and ocean meet and overlap.

A) neritic
B) intertidal
C) pelagic
D) abyssal

Question 69

Only about_______ % of the light energy absorbed by algae is ultimately synthesized into food and made available to herbivores.

A) 54
B) 2
C) 0.5

Question 70

_______ include all organisms that drift with ocean currents.

A) Nekton
B) Nerithos
C) Plankton
D) Benthos

Question 71

What is the relationship of marine life zones to the distance from a given shoreline? Briefly discuss the factors that control or cause these different zones. Where are these factors on Figure 14.12 below and is one factor more important than the others?

Question 72

The pycnocline is a rapid change in _______ with depth in the ocean.

A) salinity
B) density
C) temperature
D) biomass

Question 73

_______ refers to the total amount of dissolved materials in water.

A) Salinity
B) Runoff
C) Chlorinity
D) Halocline

Question 74

Ocean life appears to be affected by a relatively small number of variables such as temperature, density, available sunlight, available nutrients. If any one of these variables changes how do you think it might it impact the human food web?