Exam 3: Physiology and locomotion

Question 1

Properties of water: About 800x denser and 100x more viscous than air

Answer 1

Higher density and viscosity = 100x more difficult to move in water vs. Air

water hold much less oxygen than air

Need efficient mechanisms for locomotion and respiration

Question 2

Properties of water: heat capacity and conductivity

Answer 2

absorbs heat readily - water acts as a heat sink (heat exchanger)

gill make retaining body heat a difficult prob for fish

thermoregulation is rare in fish

Question 3

Properties of water: Water is a universal solvent

Answer 3

Dissolved substances in water and in fish

Osmoregulation is a challenge

Osmoregulation: maintaining an internal balance of salt and water in a fish’s body

Question 4

Fish energy budget and lifestyle

Answer 4

1) Conservation of energy
Input = Outputs (need to be balanced)
Food consumed (i) = growth + gonads (o)

2) priority of allocation

Question 5

Priority of allocation

Answer 5

1) resting metabolic rate (maintenance) + increased metabolic rate from activity = rent

2) Specific dynamic action (digestion costs) + rate of waste loss (feces and urine) = taxes

3) growth rate due to gonad synthesis + rate of somatic (body growth) = investment savings

• Energy budgets are species-specific*

Question 6

Conformers vs. regulators

Answer 6

Ancestral fish:
OsmoCONformer: body osmolality same as the environment
ThermoCONformer: body temp same as the environment

Typical fish:
OsmoREGulator: maintains chemical homeostasis
ThermoCONformer: body temp same as the environment

Endothermic teleost:
OsmorREGulator: maintains chemical homeostasis
ThermoREGulator: body temp not same as the environment

Question 7

Swimming mode:

Answer 7

Body involvement + fins used + body shape
Many fish can switch modes as needed

3 types: Undulatory, oscillatory, via fins

Question 7

Undulatory: Swimming mode

Answer 7

Anguilliform (hagfish): more drag and turbulence

Subcarangiform ( Semi hag, thin oval): middle

Crangiform (thin oval shape) : more hydrodynamic efficiency (drag force minimized)

Question 8

oscillatory: Swimming mode

Answer 8

Ostraciform (box shape):

Thunniform (torpedo-shaped):
like tuna

Question 9

via fins (fins alone): Swimming mode

Answer 9

Only use fins

Have median fins (pufferfish, sunfish)

Use combo of median, pectoral, and anal fins

Question 10

Undulatory vs. Oscillatory

Answer 10

Undulatory: Subcarangiform

Oscillatory: Thunniform
Less turbulence which makes them faster

Question 11

Swimming modes

Answer 11

Acceleration

Cornering

Cruising

Question 12

Coelacanth

Answer 12

Fina alone swimmer

Question 13

Triggerfish

Answer 13

fins alone swimmer

Question 14

Butterflyfish

Answer 14

Specialist in Cornering

Question 15

Pike

Question 16

Tuna

Answer 16

Specialist in cruising

Question 17

Surf Perch

Answer 17

Generalist

Question 18

“Robo Tuna”

Answer 18

MIT robo tuna Circa 1994,
now tuna shaped airplane that gets 22mpg

U.S navy tuna drone circa 2014

Question 19

turbulence/hydrodynamics

Answer 19

hydrodynamics:
Oscillatory Thunniform = less turbulence

Crangiform more hydro

Turbulence:
Anguilliform has more drag and turbulence

Question 20

dead zones

Question 21

Factors affecting metabolic rate

Answer 21

Body size
temp
activity

Question 22

Dead zones

Answer 22

1) salt water and fresh water join, freshwater sits on top of salt water

2) algae blooms occur when it dies it sinks to the bottom and decomposes

3) Decomposition needs oxygen and since algae bloom reduced oxygen (cause happened on top of water) in the water it makes the water warmer and no oxygen there so fish die

warmer the water the less oxygen it holds

caused by excess nutrients and warm waters