BIOL 1201 : Exam 2 Notes
Document Summary
The interior of a cell is different that its environment. How to defend the internal environment but still communicate with the external environment. Biological membranes consist of phospholipids & proteins (fig. Integral membrane proteins: amphipathic, hydrophobic (nonpolar) regions, hydrophilic (polar) region. 20 degrees celsius: do not that fluidity too literally. Functional evidence of the fluidity of membranes: figure 7. 7 & 7. 8. Figure 7. 9 the structure of a transmembrane protein. Isotonic: equivalent water potential, equivalent number of solutes dissolved, no net movement of water. If you have m solution of nacl, what happens: you have a m of na & m cl, figure 7. 15: the water balance of living cells. If solution is hypotonic, then the red blood cell is hypertonic: water moves from hypotonic solution hypertonic. Red blood cells take in water, swell, & then burst, destroying the red blood cell. In an isotonic solution, however, the blood cell is normal because there is no net movement.
