Refer to the Figures Below

Multiple Choice

Refer to the figures below. The figures show the experimental procedure and results of an investigation.The phospholipids of the cell membrane of a single cell were chemically reacted with a small fluorescent molecule so that there was uniform labeling of the fluorescent molecule across the membrane.The labeled cell was placed under a fluorescent microscope and observed as light from a laser was directed at a small region of the cell for a microsecond.The light bleached (damaged) the fluorescent molecules in that region so that the molecules were no longer able to fluoresce.In the time period following the bleaching event, recovery of fluorescence in the bleached region was observed and graphed.These results support which statement about cell membranes?

A) The cell membrane is composed of a lipid bilayer embedded with proteins.
B) Some molecules are transported via simple diffusion through the phospholipid bilayer.
C) Some membranes have more proteins than others, and some are lipid-rich.
D) Membrane phospholipids interact noncovalently and are in constant flux.
E) Phospholipids are oriented in membranes with hydrophobic tails in and hydrophilic heads out.