BIOL 1202 : Biol Exam 3
Document Summary
Phospholipids are amphipathic molecules that can from membranes. Hydrophobic regions of these proteins could exist in a non-aqueous environment. Evidence: lipids and lipid soluble material enter quicker than substances, which are insoluble in lipid. --amphipathic is a condition where a single molecule has both hydrophilic and hydrophobic regions. Evidence: the phospholipid content of red blood cells is just enough to cover the cell with two layers. The red blood cell has no internal membranes. Evidence: membranes isolated from red blood cells contains proteins in addition to lipids. Evidence: biological membranes absorb more water on their surface than artificial phospholipid membranes containing no proteins. Singer and g. nicolson phospholipid bilayer with their hydrophilic regions protruding. Membrane fluidity which are much weaker than covalent bonds. Cholesterol less fluid. fluidity that can be caused by changes in temperature. Hydrophilic regions are exposed to the aqueous environments on both sides of the membrane. passage of hydrophilic substances. membrane surface, or to integral proteins.
