Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ichthyology > Final > Flashcards

Final Flashcards

1
Q

Specific Gravity of Freshwater and Saltwater

A

1.00 & 1.026

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Specific Gravity of bone and muscle

A

2.0 & 1.055

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are two low-density fluids used to control buoyancy?

A

oils (lipids) & Salt-free fluids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

5 ways fish reduce their sinking rate

A
  1. low density compounds
  2. Lifting surfaces
  3. Reduction in bone and muscle
  4. More cartilage
  5. Swim bladder
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How does the opah create endothermy?

A

constant flapping of pectorals and minimized heat loss through counter-current heat exchangers in gills.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do canal neuromasts function?

A

they detect differential pressure between their pores that leads to a fluid shift in the canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the fluid in neuromast canals in chondrichthyes and bony fishes?

A

chondrichthyes: seawater

bony fishes: potassium rich mucus, endolymph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

modified neuromasts that detect subtle electrical field changes

A

pit organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how sensitive are shark’s electrosensors?

A

detect differential of 0.1 microvolt/cm (porbeagle shark sensitive to 0.001)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

light sensitive cells on dorsal region of brain

A

pineal body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

this area of the eye doubles light sensitivity by using reflective guanine crystals

A

the tapetum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

which type of pigments don’t match the dominant backwelling light, and why?

A

cone pigments, because this increases the contrast between the background and lighter objects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the key principal of animal colouration?

A

minimize detectability during predation and maximize it during display.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

which pigment causes dark browns, dark reds, or black, and what produces it?

A

melanin. produced by the fish

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what pigment causes bright colours, and what produces it?

A

carotenoids. produced by the fish’s food.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the role of the two nerve endings beside each chromatophore?

A

to release either epinephrine (contracts - pales) or acetylcholine (disperses - brightens colour))

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how do nocturnal and diurnal fish differ in how they offset pigments?

A

nocturnal fish don’t offset pigments, diurnal do - have as many as 5 pigments (12 in guppy).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is a large distinction between light propagation in terrestrial versus aquatic environments?

A

coloured light travels further in terrestrial environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

in what environment is disruptive colouration more useful?

A

the shallows

20
Q

why are many deep fish red?

A

red light doesn’t penetrate far. black colour could be produced by melanin, but it is toxic.

21
Q

how is uv colouration used?

A

as a high fidelity secret communication method.

22
Q

how do fish use fluorescence (3)?

A

as intraspecific communication, camouflage in fluorescing environments, and to attract plankton prey.

23
Q

what roles do directive marks play? (3)

A
  • direct predator to less vulnerable area
  • misdirect predator as to escape direction
  • increase escape with a caudal strike
24
Q

how can one differentiate advertisement from concealment?

A
  • ontogenetic sequence for each sex
  • age and size-specific mortality from each predator
  • spectral sensitivity of predator and prey
  • spectral distribution of the substrate at the depth and time where predation occurs.
  • spatial geometry of interactions.
25
Q

which 4 families are semelparous?

A
  • salmoniformes
  • clupeiformes
  • anguilliformes
  • petromyzontiformes
26
Q

why were cutthroats and rainbows originally considered separate from onchorrhyncus?

A

because they are iteroparous

27
Q

why are anadromous fish more common in northern hemisphere?

A

northern oceans are more productive, better for development.

28
Q

what is the major reason behind parental care?

A

paternity assurance

29
Q

which feeding behaviour encourages the most gill rakers?

A

benthivory - aquatic macroinverts, detritus

30
Q

what is the optimal prey size for predators that eat their food whole?

A

10% of body length

31
Q

what is the best prey measurement to predict corresponding predator boy length?

A

prey max body depth - usually 59% of predator mouth gape

32
Q

why did a less common predator (the grebe) have a disproportionate effect on stickleback genetics?

A

it was less effective at capture, therefore leaving more stickleback to escape and reproduce

33
Q

what technological evolution had the biggest impact on the commercial fishery?

A

the advent of the diesel engine

34
Q

what does the beverton and holt model determine?

A

ideal yield/recruit - 40% extraction rate

35
Q

what is a major shortcoming of fishery stock assessment equations?

A

they do not account for ecological interactions

36
Q

what is growth overfishing?

A

the removal of mass greater than the gain of biomass through growth.

37
Q

what is recruitment overfishing?

A

removal of too many adults, compromising recruitment of youth.

38
Q

what is economic overfishing?

A

removal where costs (subsidies) are more than benefits

39
Q

what is ecosystem overfishing?

A

removal of a species at a rate that significantly alters ecosystem functioning

40
Q

what three taxa account for most of human consumption?

A
  • scombridae
  • gadiformes
  • clupeiformes
41
Q

what is the primary evidence for a global fishery crisis?

A

the major decline of catch per unit effort

42
Q

how is the salmon fishery distributed?

A

70% commercial, 30% recreational (FN=14%)

43
Q

how much money does the fishery bring in globally per year?

A

$85 billion

44
Q

how much is paid to the fishery in annual subsidies?

A

$40 billion

45
Q

how much is annual catch underestimated?

A

catch is estimated at 90 million tonnes, but could be 130 million

46
Q

how much wild fish is required to feed 1 lb of farmed fish?

A

5 lbs

47
Q

how is gloabl warming affecting fish stocks?

A

warmer waters lower primary productivity, reducing food

Ichthyology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions