Fluid Environment

Question 1

pelagic

Answer 1

open water

Question 2

benthic

Answer 2

on the bottom

Question 3

neritic

Answer 3

near to shore

Question 4

oceanic

Answer 4

out in the open water

Question 5

photic

Answer 5

where light reaches

Question 6

aphotic

Answer 6

dark

Question 7

how are regions classified?

Answer 7

by physical parameters
- light
- oxygen
- temp

Question 8

eurythermal

Answer 8

wide temp tolerances
- some plankton and mammals

Question 9

stenothermal

Answer 9

narrow temp tolerances
- benthic animals like corals, sponges and clams

Question 10

homeotherm

Answer 10

regulates body temp
- mammals

Question 11

poikilotherm

Answer 11

conforms to temp
- all marine invertebrates
- most fishes

Question 12

what is an example of a homeotherm?

Answer 12

sea otter

Question 13

what is an example of a poikilotherm

Answer 13

feather duster worm

Question 14

how does oxygen vary with depth?

Answer 14

• on the surface there is high O2
• low in mesopelagic
• high O2 in deep ocean

Question 15

why does deep ocean have high oxygen levels?

Answer 15

decomposition of dead phyotplankton and marine snow

Question 16

why does the surface water have high oxygen?

Answer 16

mixing

Question 17

which ocean has minimum oxygen?

Answer 17

pacific

Question 18

why does the Atlantic Ocean not have minimal oxygen?

Answer 18

the global conveyor belt causes the warm water to move toward the Artic and oxygen is brought down when cooled through Atlantic

Question 19

how much light penetrates in coastal waters?

Answer 19

10s of a m
- more life and more turbidity

Question 20

how much light penetrates in open ocean waters or tropics?

Answer 20

100m+ as there is less chaos

Question 21

is seawater viscous?

Answer 21

yes

Question 22

what do viscous fluids resist change in?

Answer 22

shape

Question 23

what is viscosity dependent on?

Answer 23

organisms size and how fast it moves

Question 24

what is Re?

Answer 24

relative importance of inertial and viscous forces
- dimensionless
- velocity and size determine Re

Question 25

small and slow = ?

Answer 25

low Re

Question 26

large and fast = ?

Answer 26

high Re

Question 27

high Re = ?

Answer 27

turbulent

Question 28

low Re = ?

Answer 28

laminar

Question 29

what does viscosity lead to?

Answer 29

streamlines

Question 30

laminar flow

Answer 30

streamlines are all parallel and flow is regular

Question 31

turbulent flow

Answer 31

streamlines irregular to chaotic

Question 32

when happens to laminar flow when Re increase?

Answer 32

changes to turbulent flow

Question 33

what is the force exerted on an object by the liquid moving over it?

Answer 33

drag

Question 34

what is a way to reduce drag?

Answer 34

shark skin is adapted to reduce drag by shape and type of scales - dermal teeth (placoids) and placoid scales - reduce drag - break viscosity - by making turbulence

Question 35

how do ships reduce drag?

Answer 35

use riblets to reduce on their hulls - hydrophobic surfaces

Question 36

how do whales reduce drag?

Answer 36

whales' tropical migrations may be to shed their skin - shed algal growth on skin removes draf

Question 37

how is viscosity useful?

Answer 37

finding prey and avoiding predatorys

Question 38

how to copepods hide or reveal themselves?

Answer 38

shape their fluid motion - 1st antennae: flick for rapid escape - 2nd antennae: thoracic limbs create gliding and feeding current

Question 39

how do copepods organize fluid medium?

Answer 39

- copepod moves through water it creates fluid disturbance - when it hovers it creates a laminar feeding current using fine setae on second antennae -> disturbance appears as lines of equal speed of fluid (isotachs) - sensors on antennae detect changes in speed of isotachs in three directions -> detect water-borne signals in 3 dimensions (x,y,z and time)

Question 40

how does viscosity change with temperature?

Answer 40

low temp = viscosity dominates high temp = inertia dominates

Question 41

what is more developed in tropical copepods?

Answer 41

mechanisms that stop sinking

Question 42

what is more dense than water?

Answer 42

tissues

Question 43

how do planktonic plants and animals keep afloat?

Answer 43

shape-> broad shape prevents skinking projections -> long spines prevent sinking composition of tissues -> less dense tissues prevent sinking

Question 44

how to siphonophore float?

Answer 44

oil droplets have a bell with float - diatoms use same method

Question 45

who uses gas chambers to float?

Answer 45

- physalia - vellela vellela - janthina

Question 46

describe janthina

Answer 46

> raft of bubbles with mucus -> floats on ocean whole life -> eats physalia and ellela vellela

Question 47

what is another method used to float?

Answer 47

mesoglea jelly -ECM - made of hydrated collagen-like fibers - neutrally buoyant due to density - compressible and elastic for recoil when swimming

Question 48

what is transparency?

Answer 48

- provides camo - involves whole organism - evolved multiple times - in ocean, transparent tissues make animal invisible - animals are in an arms race to find prey and avoid predators

Question 49

sighting distance

Answer 49

max distance which prey animal is detected by an animal relying on visual cues

Question 50

transparency

Answer 50

- allows prey with short sighting distance to not be seen by visually orienting predators - ambush predators with short sighting distance to increase chances of entangling prey before being detected and avoided - raptors to get within striking distance before being detected

Question 51

what is polarization vision?

Answer 51

- light is polarized when entering water - birefringent tissues seen in polarized light

Question 52

what is an example of birefrigent tissues?

Answer 52

copepods muscle

Question 53

describe the squid hatchlings use polarized vision

Answer 53

regular plastic beads and polarization active PA beads -> hatchlings caught more beads that were PA than plain

Question 54

uv vision

Answer 54

- animals can see in uv light -> mantis shrimp: 12 colors, polarized light, uv light , 16 color receptors