苗10 ︶ 10-4 10 10 10 3 -2 101o 10 10 10 100 1000 Octanol water partition coefficient A. Sucrose B. Epipodophyllotoxin C. Mannitol D. Arabinose E. N-methyl nicotinamide F. Methotrexate G. Vincristine H. Urea I. Formamide J. Vinblastine K. Curare L. Thiourea M. Dianhydrogalacticol N. Glycerol o. 5- FU P. Ethylene glycol Q. Acetamide R. Ftorafur S. Misonidazole T. Propylene glycol U, Metronidazole V. Spirohydantoin mustard W. Procarbazine X. PCNU Y. Antipyrine Z. Caffeine , BCNU . CCNU Measurements were made of the ability of chemicals to penetrate the plasma membrane of cells that line the capillaries in the brain via simple diffusion. The measured values were plotted versus the octanol-water partition coefficients of the chemicals as shown above. A. What does the trend line suggest regarding the polarity of molecules and their ability to diffuse through cellular membranes?