Final answer:
Without specific fluorescence recovery data from the FRAP study, it is not possible to determine the diffusion rates of the proteins through the plasma membrane. Therefore, the diffusion rates cannot be inferred from FRAP experiments alone.
Step-by-step explanation:
The FRAP (Fluorescence Recovery After Photobleaching) study is used to analyze the mobility of molecules within the cell membrane. In the context of this question, the FRAP results are being used to determine which of several membrane-associated proteins diffuses the fastest through the plasma membrane. Generally, FRAP can provide information about diffusion rates since the speed at which fluorescence recovers in a bleached area is indicative of how quickly the molecules are moving.
However, diffusion rates through the plasma membrane can also be influenced by factors such as solubility. Nonpolar or lipid-soluble materials pass through plasma membranes more easily than polar materials, leading to a faster diffusion rate.b Both channel proteins and carrier proteins facilitate the transport of materials through the membrane, but they may differ in selectivity and transport rates. To definitively answer which molecule listed (E-APC, Armadillo, E-Cadherin, or Alpha-catenin) diffuses the fastest, specific FRAP data would be required, such as the recovery time for fluorescence in each case.
In absence of such data in the question, it is not possible to determine the diffusion rates of these proteins merely from the fact that a FRAP experiment has been conducted. Therefore, the correct answer would be E. Diffusion rates cannot be inferred from FRAP experiments without specific recovery rate data.