BIO130H1 Lecture Notes - Lecture 15: Symporter, Lysosome, Facilitated Diffusion
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BIO130H1 Full Course Notes
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Imperative to review this lecture in prep for thursday. High concentration to low concentration (down conc gradient) More hydrophobic or non-polar the molecule, the faster diffusion occurs. Multipass transmembrane proteins (not necessarily all alpha helices) Protein-lined path across cell membrane: transport polar and charged molecules. Ions, sugars, amino acids, nucleotides, various cell metabolites. Each transport protein is selective: transports specific class of molecules. Arrow on right in diagram below is concentration gradient. Channel proteins do not interact a lot or bind strongly to transported molecule. These also do not change conformation by much. Transporter can do passive or active transport - interaction happens. Some will mediate passive, others will mediate active. Both need to be considered in order to properly judge particle movement. Active transport is against electrochemical gradient: needs energy. Co transporters - one molecule down gradient, 2nd molecule goes against gradient. Uses light energy to move molecules across a gradient.
