Week 4 - Excretory System Flashcards
What is osmoregulation?
Fluid balance between intra/extra cellular liquid.
Name extracellular electrolytes
Na+
Cl-
Ca-
Name intracellular electrolytes
K+
Mg++
What is the organ with the biggest BMR
Liver
What is most metabolically expensive organ FOR ITS SIZE
kidney
Are freshwater animals osmoregulators?
Yes- all of them. Solute concentration is too low to go without it
What are the three factors of the cost of osmoregulation
- Difference in molarity
- How easily water can move across animal’s surface
- The amount of work required to move solutes in/out an animals body
Are terrestrials animals osmoregulators?
Yes- all of them
Are marine animals osmoregulators?
Most invertebrate, some vertebrate DO NOT. They osmoconform.
What is the main challenge of marine fish?
Losing water through gills. To help, drink lots and dont pee a lot. Gill lamela need to pump a lot of salt out- active transport pumps
What is the body’s principle metabolic waste?
Nitrogenous wastes
How do fish eliminate nitrogenous waste?
Straight up as ammonia since they can do it quickly through their lamela. The ammonia couples with protons to form ammonium. Ammonium is not permeable to gill filaments.
What are the nitrogenous waste dirivitives
Urea and uric acid
How many molecules of ATP is required to synthesize one molecule of Urea?
2 ATP
What nitrogenous waste do mammals excrete?
Urea
What is the nitrogenous waste of choice of birds, reptiles and snails?
Uric acid
Least toxic but most expensive to generate
What are guano deposits?
Buildup of uric acid. Great for farming because it’s a rich source of nitrogen
What is the excretory system of flatworms?
Protonephridia
Explain protonephridia
Most basic type of excretory system.
Works for osmoregulation. The tubules end with cap cells like interlocking fingers (makes up flame bulb).
Bulk flow draws fluid into tubules, then excreted.
What is the excretory system of animals with open circulatory systems?
Malpighian tubules
Explain malpighian tubules
Fingers extend out into hemolymph. It absorbs salt, nitrogenous wastes, etc. Then are emptied into the digestive tract and go out the anus
What is the excretory system of the annelid phylum
Metanephridia
Explain metanephridia
Convulates tubule works with blood capillaries.
Collects fluid for processing. Metabolites are absorbed out of the filtrate. Swollen end of metanphridia is the bladder
Describe the kidney
Houses nephrons- cortical and juxtamedullary nephrons.
What do nephrons do
Collect filtrate, reabsorb nutrients and secrete additional wastes into the filtrate.
After going through the nephron it ends up in the renal pelvis
Then the urine goes to the bladder
