osmoregulation
Internal salt management
Osmoregulation is the biological process by which organisms maintain the balance of water and dissolved substances in their bodies.
Cells and organisms must keep internal fluid concentrations within narrow limits regardless of their environment—freshwater fish excrete excess water while saltwater fish conserve it.
The kidneys play a central role in human osmoregulation.
Kidney's filtering units
- glomerulusCapillary knot filtering blood
- filtrationSeparating solids from liquids
- reabsorptionReclaiming filtered substances internally
- ureaNitrogenous metabolic waste compound
excretion · medulla · cortex · urination · antidiuretic hormone · aldosterone · renin · aquaporins
Pituitary peptide reducing urination
- vasopressinFluid-conserving pituitary hormone
- aldosteroneAdrenal hormone controlling electrolytes
- hypothalamusSubthalamic regulatory brain region
- pituitaryBrain-base hormone gland
adrenal · cortisol · feedback loop · endocrine · prolactin
Outer layer of cytoplasm
- aquaporinsMembrane proteins transporting water
- vacuoleCell's storage compartment
- contractile vacuoleWater-expelling organelle in protists
- protistUnicellular eukaryotic organism
paramecium · amoeba · plant cell · stomata · cytoplasm · intracellular · extracellular
Eleventh element, highly reactive
Equal solute concentration
- hypertonicHigher solute than reference
- hypotonicLower osmotic pressure
- concentration gradientDifference in solute density
- soluteSubstance absorbed by solvent
diffusion · semipermeable membrane · turgor · crenation · lysis · equilibrium · gradient
nephrons
Kidney's filtering units
- glomerulusCapillary knot filtering blood
- filtrationSeparating solids from liquids
- reabsorptionReclaiming filtered substances internally
urea · excretion · medulla · cortex · urination · antidiuretic hormone · aldosterone · renin · aquaporins
antidiuretic hormone
Pituitary peptide reducing urination
- vasopressinFluid-conserving pituitary hormone
- aldosteroneAdrenal hormone controlling electrolytes
- hypothalamusSubthalamic regulatory brain region
pituitary · adrenal · cortisol · feedback loop · endocrine · prolactin
cell membrane
Outer layer of cytoplasm
- aquaporinsMembrane proteins transporting water
- vacuoleCell's storage compartment
- contractile vacuoleWater-expelling organelle in protists
protist · paramecium · amoeba · plant cell · stomata · cytoplasm · intracellular · extracellular
sodium
Eleventh element, highly reactive
isotonic
Equal solute concentration
- hypertonicHigher solute than reference
- hypotonicLower osmotic pressure
- concentration gradientDifference in solute density
solute · diffusion · semipermeable membrane · turgor · crenation · lysis · equilibrium · gradient
gills
Aquatic respiratory organs
- fishGilled aquatic vertebrate
- marineRelating to the sea
- freshwaterNon-saline aquatic environment
saltwater · estuary · brackish · anadromous · salmon · eel · teleost · shark · crab · mangrove
osmoregulationdehydration
Excessive fluid loss
overhydration · electrolyte imbalance · dysregulation · water intoxication · fluid imbalance