PHYSIO lec 3 and 4

• In a semipermeable membrane separating a 1M NaCl solution and a 1M glucose solution, water moves from an area of lower solute concentration to higher solute concentration

  
• Red blood cells in a hypertonic solution shrink and appear wrinkled due to higher solute concentration causing water to move out of the cells

  
• Red blood cells in an isotonic solution have a normal appearance as the solute concentration is the same inside and outside the cells, resulting in no net movement of water
• In the normal state, the osmolality of intracellular fluid (ICF) equals that of extracellular fluid (ECF), with a total body water distribution ratio of 2:1 between ICF and ECF

  
• Hyperosmotic dehydration results in a loss of water from the body, increasing the osmolality of ECF, causing water to move from ICF to ECF, leading to cell shrinkage and potential cell death
• Table differences between isotonic, hypertonic, and hypotonic overhydration

  
• Osmosis is the movement of water across a cell membrane in response to differences in solute concentrations, with water moving from areas of lower solute concentration to higher concentration
• Osmolarity is the unit of measurement for solute concentration in terms of the number of dissolved particles in a volume of fluid or solution
• Osmotic flow depends on the concentration of particles per volume, not on the size of the particles
• Tonicity refers to the osmolarity of a solution relative to blood plasma osmolarity, with isotonic, hypertonic, and hypotonic solutions having different effects on cells
• Transcellular fluid is found in specific body parts like synovial fluid in joints, pericardial fluid in the pericardial space, and cerebrospinal fluid in the brain ventricles and subarachnoid space
• Red blood cells in hypertonic solution are crenated, in isotonic solution they are normal, and in hypotonic solution they are swollen

  
• In normal state, the osmolality of intracellular fluid (ICF) equals the osmolality of extracellular fluid (ECF), with a total body water distribution ratio of 2:1 between ICF and ECF

  
• Hyperosmotic dehydration involves a loss of water from the body, increasing the osmolality of ECF, causing water to move from ICF to ECF, leading to cell shrinkage and potential cell death
• In hyperosmotic dehydration, water moves from the ICF to the ECF to equalize osmolality, causing cell shrinkage and potential cell death

  
• Table showing differences between isotonic, hypertonic, and hypotonic overhydration

  
• Dehydration involves a loss of water and/or sodium, leading to a decrease in extracellular fluid (ECF) and/or intracellular fluid (ICF) volume
• Overhydration results from excess water, leading to increases in ECF and/or ICF volume