Excretory System Flashcards
What is osmosis?
the process by which water moves from regions of high water concentration → low water concentration
What is osmolarity?
the total solute concentration within a specific volume of solvent
What is the concentration of a hypertonic solution?
high solute
low water
cells become dehydrated and shrivel up
What nitrogenous waste is produced by aquatic organisms?
ammonia
What is the concentration of a hypotonic solution?
low solute
high water
cells swell and burst
What nitrogenous waste is produced by mammals, amphibians, sharks, and some fish?
urea
What is the concentration of an isotonic solution?
equal solutes
equal water
What nitrogenous waste is produced by birds, insects, and reptiles?
uric acid
What kind of directional system is the loop of Henle characterized by?
countercurrent flow
In what order does the excretory system work?
kidney → ureter → bladder → urethra
What are the two functions of the excretory system?
- maintain osmotic balance
- remove metabolic waste
In what order does filtrate pass thru the nephron?
renal artery
↓
glomerulus
↓
Bowman’s capsule
↓
proximal tubule
↓
loop of Henle
↓
distal tubule
↓
collecting ducts
What does secretion mean?
solutes are excreted from the blood into the nephron
What does reabsorption mean?
solutes are excreted from the nephron back into the blood
What happens during glomerular filtration?
- blood enters kidney thru renal artery
- fluid from blood in glomerulus enters into the Bowman’s capsule
- fluid is processed as filtrate