The mesopelagic, which is characterized by no sunlight, begins at about 200 m deep.
The correct order for the three zones of the deep sea in increasing depth are:
|A)||Bathypelagic, abyssopelagic, hadal|
|B)||Mesopelagic, epipelagic, abyssopelagic|
|C)||Abyssopelagic, hadal, Bathypelagic,|
|D)||Epipelagic, mesopelagic, bathypelagic|
The Deep Sea Benthos occurs only below the hadopelagic zone.
Nautilus achieves neutral buoyancy by which of these mechanisms?
|A)||Removing ions from chambers in its shell.|
|B)||Moving lipids between chambers in its shell.|
|D)||A thin, light shell.|
Mesopelagic organisms are dominated by:
|A)||Cnidarians, chaetognaths, crustaceans, fishes, and squids.|
|B)||Diatoms, copepods, chaetognaths, and fishes.|
|C)||Copepods, cephalopods, foraminiferans, and large fishes.|
|D)||Medusae, ctenophores, copepods, and squids.|
A biologist takes a surface plankton tow at night. Which of these animals caught in the tow surely is a vertically migrating mesopelagic animal?
|B)||A squid with photophores|
|D)||The larval stage of a barnacle|
Most of the fish species common to the mesopelagic are characterized by a small size, many sharp teeth, and a row of ventral (belly) photophores.
A whalefish is a mesopelagic fish with no scales, weak bones, and flabby flesh. What can you conclude about its lifestyle?
|A)||It migrates vertically.|
|B)||It must be an active swimmer.|
|C)||It eats detritus.|
|D)||It is a sit-and-wait predator.|
Which of these conditions do vertically migrating mesopelagic animals encounter?
|A)||Large changes in temperature.|
|B)||Anoxic water below the thermocline.|
|C)||High primary productivity at depth.|
|D)||No light at all.|
The greatest biological limiting factor that effects the size and metabolic rates of mesopelegic fishes is:
|A)||Lack of ambient light.|
|B)||The energy requirements to be bioluminescent.|
|C)||Eutrophication of mid-depth waters.|
|D)||Limited food availability|
The sonar echoes of the Deep Sea Layer or Deep Scattering Layer (DSL) are due to:
|A)||Exoskeletons of shrimp.|
|B)||Bones in fishes.|
|C)||gas-filled swim bladders.|
|D)||Shells of pteropods.|
Bioluminescence can have a role in all of these functions except?
|C)||Orienting the organism to the surface during vertical migration|
Which of these organisms can be very abundant in the mesopelagic?
Mesopelagic fish rely more heavily upon _________ to avoid predation than epipelagic fish.
|B)||Spines and scales|
Bathypelagic fishes usually have photophores on the head and sides of the body instead of on the ventral surface.
Fishes of the deep pelagic, such as the anglerfish, cruise constantly in search of scarce food.
To find a mate, a male deep-sea anglerfish uses:
|B)||Light patterns from rows of photophores.|
|C)||A powerful sense of smell.|
Deep-sea organisms do not usually survive when brought to the surface due to the severe changes of:
Due to the effects from respiration and bacterial decay coupled with lack of photosynthesis a layer exists at around 500m/1,600ft that is very difficult to survive in called the:
|C)||Oxygen Minimum Zone/Layer|
Another adaptation of many deep-sea fishes to the problem of finding a breeding mate in a dark sparsely-populated environment is that many have become:
In fishes, bioluminescence is produced by:
Life-spans of deep-sea organisms tend to be ___________ than those of epipelagic or mesopelagic organisms.
|B)||The same as|
|D)||Their life-spans cannot be calculated.|
Among the most common large deep-sea benthic deposit feeders are:
Which of these animals probably lives on the deep-sea floor?
|A)||A small, thin fish with large teeth and rows of photophores|
|B)||A shrimp carrying several hundred small eggs|
|C)||A suspension-feeding clam|
|D)||A scavenging amphipod with an expandable gut|
Mesopelagic fish like epipelagic fish make frequent use of __________ to save energy and yet avoid predation.
Which of these ecosystems possibly contains the greatest amount of biodiversity?
|D)||The deep ocean floor|
Which substance is the basis of the chemosynthetic food-chain at the hydrothermal vents?
Which of these occurs at the cooler vents associated with trenches?
|A)||Tube worms and ostracods|
|B)||Anglerfish and phytoplankton|
|C)||Archaea and bacteria|
|D)||Sea spiders and nautilus|
Primary producers at hydrothermal vents include:
Which of these colors appears as black in the bathyopelagic, abyssopelagic, and hadopelagic zones and is thus used by some fish and shrimp?