ANT 2100 1st Edition Lecture 8I. Membrane Transport a. Selectively permeable 1. Cell membrane allow only certain molecules to pass through 2. If a molecule can pass through the membrane is said to be permeable to the molecule 3. Permeability- ability of a molecule to pass through a membrane b. Passive transport 1. Does not require ATP 2. Movement of molecules down a gradient 3. Directly proportional 4. Inversely proportional 5. Types of passive transport (simple diffusion, osmosis, filtration, facilitated diffusion) c. Simple Diffusion 1. Movement of lipid-soluble molecule across a membrane 2. Contains oxygen, carbon dioxide, and small lipid molecules d. Osmosis 1. Movement of water across a membrane 2. Movement of water driven by osmotic pressure 3. Osmotic pressure is a force that pulls water towards the membrane andis dictated by the concentration of solutes in a fluid 4. Osmolarity- osmoles of solute/liter of fluid 5. Osmolality- osmoles of solute/ kg of solvent 6. NORMAL BLOOD OSMOLALITY: 280-300mOsm/kg e. Tonicity 1. Unitless comparison of osmolality between two fluids f. Isotonic fluid 1. Osomolality of both fluids is the same 2. Osmotic pressure of both fluids is the same 3. No net movement of water g. Hypertonic fluid 1. Has higher osmolality than fluid compared to it 2. Water moves towards hypertonic fluid 3. Higher osmolality 4. Higher osmotic pressure h. Hypotonic fluid 1. Has lower osmolality than fluid compared to it 2. Water moves away from hypotonic fluid 3. Lower osomlality 4. Lower osmotic pressure These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a