The classic demonstration that cell plasma membranes are composed ofbilayers depends on the following kinds of data:• The membrane lipids from 4.74 x 109 erythrocytes will form a monolayerof area 0.89 m2 when spread on a water surface.• The surface of one erythrocyte is approximately 100 μm2 in area.Show that these data can be accounted for only if the erythrocyte membraneis a bilayer.

The classic demonstration that cell plasma membranes are composed ofbilayers depends on the following kinds of data:• The membrane lipids from 4.74 x 109 erythrocytes will form a monolayerof area 0.89 m2 when spread on a water surface.• The surface of one erythrocyte is approximately 100 μm2 in area.Show that these data can be accounted for only if the erythrocyte membraneis a bilayer.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter11: The Blood

Section: Chapter Questions

Problem 1SQE

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In 1925, E. Gorter and F. Grendel used an apparatus like that described in Problem 1 to determine the surface area of a lipid monolayer formed bylipids extracted from erythrocytes of several animal species. They used a microscope to measure the dimensions of individual cells, from which they calculated the average surface area of one erythrocyte. They obtained the data shown in the table below. Were these investigators justified in concluding that “chromocytes [erythrocytes] are covered by a layer of fatty substances that is two molecules thick” (i.e., a lipid bilayer)?
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