BIOL 111 Lecture Notes - Lecture 8: Cell Membrane, Amphiphile, Phospholipid

• School: Texas A&M University
• Department: Biology
• Course: BIOL 111
• Professor: Tag Andrew

Document Summary

The membrane is a collage of different proteins embedded in the uid mosaic model. Plasma membrane: exhibit selective permeability; allows some substances to cross it more easily than others. Plans change their lipid composition in response to temperature. Steroid cholesterol: has affects on membrane uidity at different temperatures. Increases for the at low temperatures; decreases for the at high temperatures. Hydrophobic molecules: lipid soluble and can past through the membrane rapidly. Polar molecules: do not cross the membrane rapidly. Transport proteins: help with the passage of materials through the membrane. Membranes are distinct inside and outside faces (affect the movement) In eukaryotes membrane proteins lipids are synthesized in the er and golgi apparatus. Passive transport: diffusion across a membrane without the use of energy. Osmosis: movement of water across a semi permeable membrane. Is affected by the concentration gradient of dissolve substances. Tonicity- the ability of a solution to cause a cell to gain or lose water.