Physiology Flashcards
How does water enter an animal’s system
1) Preformed water (food and drink)
2) Metabolic water production
How do electrolytes enter an animal’s system
1) Preformed water (food and drink)
How does water leave an animal’s system
1) Respiration
2) Cutaneous water loss
3) Feces
4) Urine
How do electrolytes leave an animal’s system
1) Feces
2) Urine
How do freshwater fish osmoregulate?
1) They are hyperosmotic
2) They are at risk of hypervolemia and hyponatremia
3) They produce dilute urine
4) They uptake electrolytes in the gills
How do marine fish osmoregulate?
1) They are hypoosmotic
2) They are at risk of hypovolemia and hypernatremia
3) They actively drink seawater
4) They produce concentrated urine
5) They excrete electrolytes through chloride cells in the gills
How do elasmobranchs osmoregulate?
1) They have TMAO and urea in their blood which increases blood osmolality
2) Therefore, they are hyperosmotic
2) They are at risk of hypervolemia and hyponatremia
3) Concentration of saltwater is higher in water than in their blood which is why they need a rectal salt gland
How do marine reptiles osmoregulate?
1) They produce uric acid which, although requires a lot of water, allows some urine to pass backwards into the hindgut for water resorption
2) They have a salt gland that allows them to drink sea water while maintaining osmotic balance.
How do marine birds osmoregulate?
1) They produce uric acid which, although requires a lot of water, allows some urine to pass backwards into the hindgut for water resorption
2) They have a salt gland that allows them to drink sea water while maintaining osmotic balance.
How do marine mammals osmoregulate?
1) Very concentrated urine (reniculate kidney)
2) Apneustic breathing
3) Nasal turbinates
4) Lipid rich diet
5) Lipid-dense milk (when lactating)
Nitrogenous waste in different organisms
1) Ammonia = most aquatic animals (fish)
2) Urea = mammals, most amphibians, sharks
3) Uric acid = birds, insects, reptiles
Which marine mammals drink seawater?
1) Sea otters, common bottlenose dolphin, hooded seal, harp seal (while feeding)
2) Galapagos fur seal, short-beaked common dolphin, and short-finned pilot whale while fasting
Surface area scaling
Volume ^2/3
Mass ^ 1
Length^2
Volume
Length^3
Mass ^ 1
Fundamental variables of scaling relationships and derived variables
1) Mass
2) Length
3) Time
Derived
1) Density
2) Velocity
3) Acceleration
4) Force
5) Stress
6) Work
7) Power
8) Mass specific power
9) Biomass density
10) Production
11) Productivity
Equation for scaling of body mass
Y=aMsub(b)^b
a = proportionality constant
b = mass exponent
In log form:
log(Y) = log(a) +b*log(Msub(b))
Things that scale with body mass
1) Blood volume of mammals
2) Lung volume of mammals
3) Resting metabolic rate: Mass^.75
3) Mass-specific metabolic rate: Mass^-.25
4) VO2max: Mass^.75 (.81)
5) Specific net transport cost ^-.25
Scaling of metabolic rate
1) Total Metabolic Rate: Mass^.75
2) Mass-Specific Metabolic Rate: Mass^-.25
Environmental implications of scaling of metabolic rate
1) Small mammals degrade more energy per unit mass than large mammals
2) Therefore, a given energy supply will run
out more quickly for small animals
3) Or, looked at per unit time, a given energy supply will support a much smaller biomass of mice than of large moose or elephants
4) So larger species are better at getting and using energy than smaller species from similar taxa (better competitors)