Deck 16: The Ocean Depths

Question 1

The deep-sea scavengers include animals that feed on:

A)Deep-sea plankton.
B)Bottom meiofauna.
C)Particulate organic matter.
D)Dead animals.
E)Bacteria.

Answer 1

D

Question 2

Which of the following is least likely to be seen in a vertical non-migrating mesopelagic fish?

A)Weak bones
B)Swim bladder
C)Flabby muscles
D)Small size
E)Large eyes

Answer 2

B

Question 3

The tubular eyes of some mid-water animals are adapted for:

A)Increasing the field of vision
B)Producing light
C)Seeing in the complete absence of light
D)Sensing changes in depth
E)Sensing changes in salinity

Answer 3

A

Question 4

Bioluminescence is used by mid-water animals in all of these except in:

A)Communication.
B)Warning coloration.
C)Attracting prey.
D)Counter illumination.
E)Escaping from predators.

Question 5

An important feeding adaptation among deep-sea fishes:

A)Migration to shallower water to feed.
B)Feeding on males,hence the term "male parasitism".
C)Ability to eat prey bigger than themselves.
D)Strong muscles that allow them to move fast to catch any available prey.
E)Absence of a stomach.

Question 6

Which of the following is not true regarding the deep-scattering layer (DSL)?

A)Position rises at night and moves down during the day
B)Comprise of fish,shrimp,squids and jellyfish
C)Found at depths of 300-500 meters
D)Discovered by sonar during WW II
E)Position is deeper on nights with a new moon

Question 7

The deepest of ocean waters are classified as:

A)Bathypelagic.
B)Hadal pelagic.
C)Abyssopelagic.
D)Mesopelagic.
E)Lower epipelagic.

Question 8

In addition to food,deep-water animals depend on the surface for:

A)Light.
B)Carbon dioxide.
C)Chlorophyll.
D)Oxygen.
E)All answers are correct.

Question 9

The mesopelagic zone extends from about 200 m to about:

A)300 m.
B)500 m.
C)1,000 m.
D)2,000 m.
E)4,000 m.

Question 10

A chambered nautilus is a species of.

A)Cnidarian.
B)Bathyopelagic fish.
C)Deep ocean isopod.
D)Cephalopod.

Question 11

The deep-sea benthos consists mostly of:

A)Deposit feeders.
B)Filter feeders.
C)Herbivores.
D)Omnivores.
E)Carnivores.

Question 12

Which of these groups of planktonic organisms would be least likely to be living in the mesopelagic?

A)Arrow worms
B)Ostracots
C)Copepods
D)Diatoms
E)Pteropods

Question 13

Pheromones are special chemicals that are used to:

A)Digest food.
B)Attract mates.
C)Catch prey.
D)Transport oxygen.
E)Produce bioluminescence.

Question 14

The mesopelagic zone refers to the ocean depths in which there is:

A)Enough light to support plant growth.
B)No light at all.
C)Dim light,but not enough for plant growth.
D)Enough light for primary production by bacteria.
E)Dim light,but enough to support only some hardy plants.

Question 15

The water below the oxygen minimum layer has:

A)No oxygen at all.
B)Only very small traces of oxygen.
C)Some of the oxygen it had when it left the surface.
D)Most of the oxygen it had when it left the surface.

Question 16

The zone immediately below the bathyalpelegic zone is called the:

A)Abyssopelagic.
B)Hadal pelagic.
C)Subtidal.
D)Subbathyal.
E)Mesopelagic.

Question 17

Deep-sea pelagic fishes are characterized by all of the following except:

A)Small eyes.
B)Absent or reduced swim bladder.
C)Color spotted with red.
D)Flabby muscles.
E)Large mouth and teeth.

Question 18

The presence of bioluminescent organs on the underside of mid-water fishes is involved in:

A)Counter shading.
B)Enlargement of silhouette.
C)Creating a transparency effect.
D)Cryptic coloration.
E)Counter illumination.

Question 19

Photophores are:

A)Specialized eyes.
B)Buoyancy-regulating organs.
C)Specialized jaws.
D)Light-sensitive organs that lack the lens of true eyes.
E)Light-producing organs.

Question 20

The main oceanic thermocline is located:

A)In the mesopelagic.
B)Above the mesopelagic.
C)Below the mesopelagic.
D)It varies since the thermocline disappears in the tropics.
E)It varies since the thermocline moves up and down in the water column depending on the amount of oxygen.

Question 21

The major advantage that deep-sea benthic animals have over pelagic ones is that their food:

A)Is easier to digest.
B)Falls to the bottom and stays in one place,thus being available for a longer time.
C)Gets to be eaten before it gets to pelagic animals.
D)Gets decayed at much faster rates by chemosynthetic bacteria.
E)Produces less detritus.

Question 22

Recent discoveries have shown the Challanger Expedition and other 19th-century oceanographic expeditions assumption that the deep ocean had no ______________ was incorrect.

A)Sediments
B)volcanic activity
C)water movement
D)biodiversity

Question 23

Bacteria thriving around deep-sea hydrothermal vents are:

A)Photosynthethic.
B)Symbiotic.
C)Heterotrophic.
D)Parasitic.
E)Chemosynthetic.

Question 24

A shrimp that occurs in large numbers around deep-sea hydrothermal vents does not have eyes.Light-sensitive cells on the top of the body,however,appear to be used to detect faint light from:

A)Bioluminescent predators.
B)The surface.
C)Faint glow around vents.
D)Bioluminescent prey.
E)Mates.

Question 25

Deep sea gigantism is most common in:

A)Crustaceans.
B)Polychaetes.
C)Brittle stars.
D)Sea stars.
E)Sea spiders.

Question 26

An unknown fish has been brought to you to examine.This fish is black,relatively small with small eyes and weak,flabby muscles.This fish is most likely from the:

A)Mesopelagic (vertical migratory).
B)Mesopelagic (vertical non-migrator).
C)Epipelagic.
D)Deep pelagic.
E)Deep-sea benthic.

Question 27

The "experimental lunch" that was left on the Alvin as it rested on the bottom revealed that deep-sea bacteria:

A)Do not exist at all.
B)May cause diseases in humans exposed to them.
C)Break down organic matter faster than in shallow water as a result of high pressure.
D)Grow slower than shallow-water species.
E)Are identical to those found in shallow water.

Question 28

The most common fish in the mesopelagic are:

A)Lanternfishes.
B)Bristlemouths.
C)Lancetfishes.
D)Cutlassfishes.
E)Hatchetfishes.

Question 29

The energy source for the bacteria that thrive around deep-sea hydrothermal vents is:

A)Hydrogen sulfide.
B)Light.
C)Heat from the hydrothermal vents.
D)Detritus.
E)Tube-worm tissues.

Question 30

The reason for deep sea gigantism is:

A)Predation.
B)Related to reproduction.
C)Competition for food.
D)Competition for space.
E)Not known.

Question 31

The condition that creates the largest problem for animals in the deep sea:

A)Salinity changes.
B)Temperature changes.
C)Pressure changes.
D)Food availability.

Question 32

The most numerous organisms on the deep sea floor are:

A)Macrofauna.
B)Epifauna.
C)Endofauna.
D)Meiofauna.
E)Infauna.

Question 33

Hermaphroditism and male parasitism is most common in:

A)Fishes.
B)Tube worms.
C)Clams.
D)Crabs.
E)Shrimp.

Question 34

Bioluminescence in mesopelagic organisms is produced by:

A)Photophores.
B)Specialized cells.
C)Secretions of lucifern.
D)All answers are correct.
E)Photophores and Specialized cells only.

Question 35

The giant deep-sea hydrothermal vent tubeworm feeds on:

A)Phytoplankton that utilize the heat for primary production.
B)Detritus from vent deposits.
C)Small bottom animals such as brittle stars.
D)Deep-sea bottom fishes that cluster around the vents.
E)It filter-feeds on chemosynthetic bacteria.