BIO130H1 Lecture : Second Half Lecture 3
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BIO130H1 Full Course Notes
Verified Note
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Document Summary
Lipid bilayer permeability: hydrophobic (non-polar) molecules are permeable. Polar molecules and ions are impermeable (h2o exception: movement across membrane is through diffusion, high to low concentration. Membrane transport proteins overview: used to transport polar molecules and ions across membrane, multi-pass molecules. Transporter proteins: carrier proteins, binds to specific solute, undergoes conformational change, conformational change allows protein to physically direct solute movement, can be either passive or active transport. Channel proteins: create a passage to allow the passing of molecules. Passive: diffusion across membrane from high to low concentration, with electrochemical gradient, no energy needed. 8/12: active: diffusion across membrane from low to high concentration, against electrochemical gradient energy is needed. Transports two molecules in same direction, active transport. Na+/glucose symporter, na+ provides energy for glucose against gradient. Transports two molecules in opposite directions, active transport. Free energy from one molecule is used to transport other molecule against electrochemical gradient: secondary active transport, use of energy not from atp.
