Chapter 44 (Module 3) Flashcards
Osmosis:
movement of water down its gradient across a selectively permeable membrane
Osmolarity:
the solute concentration of a solution
Hyperosmotic side:
higher solute conc., lower free H2O conc.
Hypoosmotic side:
lower solute conc., higher free H2O conc.
Selectively permeable membrane: (2)
- divides the solution and allows water to pass from one side to the other
- prevents solutes from moving from one side to the other
Importance of Osmoregulation:
- consistant internal enviroment (pH, salinity, etc)
- animals must maintain constant osmoregulation (gain and lose of water)
How do animals loose water: (4)
- Urine
- Feces
- Perspiration
- Breath
Osmoconformers: (4)
- isosmotic with their surroundings; do not regulate their osmolarity
- conserves energy
- narrow range of salinities
- ALWAYS saltwater organisms
Osmoregulators: (2)
- expend energy to control water uptake and loss in a hyperosmotic or hypoosmotic environment.
- ALL vertebrates
Freshwater fish: (2 problems they face)
- hypoosmotic medium (water wants to enter cells)
- water gained by osmosis; solutes lost into water by diffusion
Saltwater/marine fish: (2 problems they face)
- hyperosmotic medium (water wants to leave the cells)
- water lost by osmosis; solutes gained by diffusion
Terrestrial animals: (2 problems they face)
- Hyperosmotic medium (water wants to leave the cells)
- water is lost from evaporation and during breathing
Deamination:
result of the metabolic process –> typically as ammonia
Excretion:
must be dissolved in water
Forms of removal: (3)
- Ammonia: aquatic animals, most bony fish
- Urea: mammals, amphibians, sharks
- Uric acid: birds, reptiles, insects
Strategies for removal: (3)
- Flushing: dump NH3 into water at the gills
- Detoxification: NH3 is converted to urea and transported to kidneys
- Insolubilization: NH3 is converted to uric acid and excreted as a solid or kept in an egg (uses less water)
Filtration:
body fluids pass through special structures to remove unwanted materials
Reabsorption:
reclaiming valuable solutes from the filtrate
Secretion:
adding nonessential solutes and water to the filtrate
Excretion:
processed filtrate containing nitrogenous waste is released from the body
Protonephridia:
- found in protonephridia
- taken in by cilia in the flame bulb, filtered, and pushed through tubules
Metanephridia:
- found in earthworms, Annelida
- Uses a collecting tubule and a network of capillary networks
Malpighian tubules:
- found in some insects
- bring salt, water, and N waste into the Hindgut
Blood to the Kidney: (3)
- blood flows to kidneys in renal artery
- branches into glomeruli (capillary beds)
- fluid that does not go into kidneys go to efferent arteriole and peritubular capillaries