Deep Sea Adaptations

Question 1

what is used to map and explore the ocean floor?

Answer 1

titanic sinking - an impetus for development of SONAR

Question 2

what was used to determine depth?

Answer 2

lead line
-> sounding line
- used lead weight that drops to the floor to measure the depth

Question 3

what is echo sounding?

Answer 3

uses pulses of sound that rebound from the ocean floor

Question 4

how are 3D maps generated?

Answer 4

side-scan sonar
- uses conical or fan shaped pulses of sound

Question 5

what does high frequency give?

Answer 5

high resolution

Question 6

multibeam scanning

Answer 6

• high resolution of seafloor topography
• uses multiple frequencies of sound simultaneously-> diff info given based off what it bounces off
• creates swaths of seafloor that are patched together by software

Question 7

satellite altimetry

Answer 7

• measures time taken by radar pulse to travel from satellite antenna to surface of ocean and back to satellite receiver
• yield sea-surface heights
• water forms bump over mountains because gravity causes attraction of water to feature

Question 8

arctic ocean seafloor features map

Answer 8

sea ice -> declining so more area available for oil and gas and importation

Question 9

what were remote observations originally limited to?

Answer 9

tows and hauls until methods to get humans under water developed
- see animals in habitats and see ecosystems as a whole

Question 10

ocean exploration machines

Answer 10

• pisces iii
• pisces iv
• alvin
• johnson sea link
  -> collects specimens using nets

Question 11

remote operated vehicles

Answer 11

• jason, woods hole
• MBARI
• ROPOS

Question 12

what are the sunlight zones?

Answer 12

• euphotic
• disphotic
• aphotic

Question 13

what are the biozones?

Answer 13

• epipelagic
• mesopelagic - small light, no floating phytoplankton, no plants, steep change in thermocline
• bathypelagic - open ocean, pressured
• abyssopelagic - inside deep sea trenches, deeper than sea floor, cold, no sun

Question 14

how much biomass is in the top 200m?

Answer 14

83%

Question 15

how much biomass is in the hadal zone?

Answer 15

<0.8%

Question 16

what is found in deep water?

Answer 16

• fine sediment
• deposit feeders - ingest particles associated with sediment, dig through sediment
• suspension feeders where currents are strong - glass sponges
• food is scarce

Question 17

why is the deep sea hard to live in?

Answer 17

• cold water
• total darkness
• little oxygen
• very little food -> food limitation drives evolution

Question 18

how is marine snow made?

Answer 18

• dead organisms -> mostly planktonic (phyto), coastal has more diversity (kelp…)
• fecal pellets-> dense package that can sink fast
• mucus products -> filter structure secreted by zooplankton
• secretion of organisms -> extracellular polymers cementing bacterial cell walls, mucus sheets produced by diatoms, cyanobacteria colonies
• bubble -> burst DOC condenses into POC (dissolved organic carbon to particulate organic carbon)

Question 19

how do deep sea organisms adapt to pressure?

Answer 19

• reduce or lack of air-filled swim bladders -> can be crushed due to high pressure
  -> sperm whales: cool down by moving core blood either toward or away from body
• pressure-resistant structures

Question 20

how do deep sea organisms adapt to low food?

Answer 20

• small body
• vertical migration
• detritivores/generalized omnivores
• mouth/gut morphology

Question 21

how do deep sea organisms adapt to few mates?

Answer 21

dwarf males

Question 22

how do deep sea organisms adapt to lack of light?

Answer 22

• eyes: reduced or no eyes (bathy)
  -> tubular eyes with 2 retinas (meso)
• bioluminescence -> communication

Question 23

how does viper fish adapt to feeding in deep sea?

Answer 23

large teeth
hinged jaw

Question 24

how does chiasmodon tiger adapt to feeding in deep sea?

Answer 24

vast stomach to hold onto prey

Question 25

pelican or gulper eel

Answer 25

- vast mouth with hinged jaw - long undulating body - capture large fish - feeds on crustaceans like Rorquales

Question 26

how do tripod fish adapt?

Answer 26

- sit and wait predator - evolved variation of fins - uses little energy while waiting for prey

Question 27

what kind of siphons do carnivorous tunicates have?

Answer 27

atrial - water is pushed out oral - water comes in

Question 28

what is the point of the branchial basket?

Answer 28

collects filtered food

Question 29

what are carnivorous sponges?

Answer 29

- lycopodina - harp sponge - ping pong tree sponge - amphipod crustacean

Question 30

what kind of migration do mesopelagic fish do?

Answer 30

vertical or non- migrations

Question 31

compare vertical and non-migrators

Answer 31

- vertical: swim bladder, well-developed bones (allows to move up and down water column) - non-migrators: no swim bladder, weak bones, flabby muscles - similarities: black/black-silver eyes, large eyes, large mouth, photophores, small body size

Question 32

how do angler fish mate?

Answer 32

parasitic males - lures - females are large and sluggish - males are tiny and muscular swimmers - finding females - female is located and they bite into stomach. mouth and jaw regresses and tissues and blood systems fuse

Question 33

what is bioluminescence?

Answer 33

- emission of ecologically functional light by living organism - light is produced by chemical rxn within organism - no input of energy

Question 34

who has bioluminescence?

Answer 34

- marine bacteria - dinoflagellates - all major phyla

Question 35

how does bioluminescence work?

Answer 35

enzyme + substrate + co-factors -> excited state -> release of light + enzyme + substrate

Question 36

what is the core of bioluminescence?

Answer 36

luciferin

Question 37

describe luciferin

Answer 37

- strong antioxidative properties - detoxifies tissues by taking up oxygen free radicals - brought into system by diet, synthesized internally - originated to detoxufy oxygen

Question 38

coelenterazine

Answer 38

- most common version of luciferins - in cnidarians, molluscs, chaetognaths, fish - first found in cnidarians - can act alone together with aequorin (luciferase) - found in ALL tissues of animals -> highest concentration in digestive gland, liver hepatopancrease, organs with high levels of oxidative reactions

Question 39

aequorin

Answer 39

- luciferase(enzyme) that requires calcium - photoprotein (co-factor) bc requires calcium to work with luciferin

Question 40

bacterial luciferin

Answer 40

- harnessed by other animals and used for light emission - vibrio: marine bacterium that is an endosymbiont in squid - luminescence is dependent on cell density

Question 41

pygmy squid

Answer 41

- Eurprymna scolopes - lives on reef flats in Hawaii - forages for fish at night

Question 42

what do light organs contain?

Answer 42

Vibrio bacteria - at right population bioluminesce - squid light organ has shutters - like eyelids - uses bioluminescence to counter-shade against moonlight so prey wont see its shadow

Question 43

what is the purpose of bioluminescence?

Answer 43

- lure: Blackdevil has luminescent lure to attract prey - burglar alarm: startling predators of your predator, working hypothesis - alarm: shrimp and pyrosomes (fire animals), stop feeding and swimming current, shrimp excrete light to alarm predator - counter illumination: squid E. scolopes buries in sand during day and forages at night

Question 44

how do pyrosomes alarm or warn other colonies?

Answer 44

- mechanical signal - stimulates the brain - causes cilia to stop beating on branchial basket - triggers light to flash - seem by eye in neighboring individual in colony and neighboring - bc cilia stop the water "jet" stops. colony sinks - out of the bad water