BIO202H5 Lecture Notes - Lecture 4: Active Transport, Semipermeable Membrane, Extracellular Fluid
Document Summary
Risk of losing water through osmosis or gaining salts through diffusion. Animal is hyposmotic to seawater (osmolarity of seawater higher in environment than in body: water conservation of primary importance. Risk of gaining too much salt ions through diffusion. Risk of losing too much water through osmosis. Osmosis: movement of water through a semipermeable membrane. H2o, proteins, and carbs move across with the help of proteins passively or actively. If you have a higher solute concentration on the outside, water will move from the inside to the outside to balance the concentration of solute (make it lower) Primary active transport: you need energy to transport a substance (usually against its concentration gradient) Secondary active transport: symport/co-transporters (transport two different solutes across the membrane in the same direction) or anti-ports (transport a two different solutes across the membrane in the opposite direction) Animal is hyperosmotic to the water it lives in. Risk of too much water entering the body through osmosis.
