L4-5 Water & Electrolytes Flashcards
Understand the composition and role of the body fluid compartments in terms of osmosis and membrane permeability.
The extracellular fluid (ECF) consists of (2)…
Plasma and interstitial fluid
Plasma and interstitial fluid are ? in composition
Similar
Intracellular fluid ion composition is different from the ECF, there is a state of…
Chemical Disequilibrium
Chemical disequilibrium between ECF/ICF is maintained by (2)…
- Active transport of solutes across membrane
2. Membranes are partially permeable, acting as a barrier to solute movement
The ECF/ICF are in a state of Osmotic Equilibrium because…
⚖️
Water is able to move freely between cellular compartments, across the partially permeable membrane
Two solutions in a state of Osmotic Equilibrium can be said to be…
Isosmotic (or Iso-osmotic)
Osmolarity is equal to the Molarity (M)…
Multiplied by the number of particles (moles)
If we add water to a solution, the molarity decreases, therefore the osmolarity…
Decreases ⬇
In body fluid compartments, osmotic equilibrium occurs at…
300 mOsM (miliosmoles)
Water will move from ? to ? osmolarities
Lower to Higher ⧡
Counter ions attracted to highly charged metabolites within the ICF create the danger of…⚠️
The ICF becoming Hyperosmotic relative to ECF
To prevent the ICF becoming hyper osmotic, the cell…
Actively pumps out inorganic ions
The ionic composition varies greatly between the ECF/ICF. The total ionic concentration is…
Very similar
