Biochemistry 3381A Lecture Notes - Lecture 11: Membrane Transport Protein, Facilitated Diffusion, Passive Transport
Document Summary
Tissue (frog leg) on 2 different types of metal, the leg would contract. All processes depend on membranes being permeable, specifically selectively permeable. The plasma membrane is normally impermeable to ions: the more polar it gets or even charged, harder it is to get through. Idea of a carrier protein, doesn"t require energy and shape changes when recognising the solute, changes shape, and then solute transferred through membrane. Causes facilitated diffusion: water filled hole which something can pass through, this will be a channel protein, a carrier protein changes its conformation and move the bound molecules to the other side of the membrane. Only occurs where there is diffusion from high to low concentration. Er - calcium binding proteins within er, to keep cytosolic levels at very low levels (100nm compared to 0. 5mm in the er) Lysosomes (ph4. 5) lots more protons in the organelle than in the cytosol (ph7. 2) Mitochondria (ph7. 8) more alkaline on the inside (ph7. 2)