Osmoregulation

Osmoregulation overview

1. Osmoregulation Bethany Eudy

2. What is Osmoregulation ? The process by which animals control solute concentrations and balance water gain and loss This is essential in the fluid environments in cells, tissues, and organs http://t3.gstatic.com/images?q=tbn:ANd9GcRaqie-Vh5fPrxZ2gsTs_mMP7m3vT1CPIya95Kc7JqdZe4pDSMn

3. Osmosis and Osmolarity Water enters and leave the cells through osmosis Osmolarity - Osmotic pressure Isoosmotic - 2 solutions separated by a selectively permeable membrane, but with the same osmolarity

4. Hyperosmotic - greater concentration of solute in 2 solutions Hypoosmotic - diluted concentration of solute in 2 solutions

5. Osmotic Challenges Maintain water two ways Osmoconformer (marine animals)- isoosmotic with its surroundings Osmoregulator – controls internal osmolarity Stenohaline - animals that cannot tolerate changes in external osmolarity Euryhaline - Animals that can survive large changes in external osmolarity

6. Energetics of Osmoregulation Osmoregulators must expend energy to maintain osmotic gradients Use active transport to manipulate solute concentrations Osmoregulation accounts for 5% or more of resting metabolic rate of many fishes

7. Transport Epithelia in Osmoregulation Osmotic regulation relies on kinds of transport epithelium Transport epithelia move specific solutes in specific directions