The Molecular
Constituents of Membranes
Each
Membrane Has a Characteristic Lipid Composition
Membranes
with Different Funetions Have Different Proteins
The Supramolecular
Architecture of Membranes
A Lipid
Bilayer Is the Basic Structural Element
Membrane
Lipids Are in Constant Motion
Membrane
Proteins Penetrate and Span the Lipid Bilayer
BOX 10-1 Electron
Microscopy of Membranes
Membrane
Proteins Are Oriented Asymmetrically
Integral
Membrane Proteins Are Insoluble in Water
Some
Integral Proteins Have Hydrophobic Transmembrane
Anchors
BOX 10-2 Predicting
the Topology of Membrane Proteins
The
Structure of a Crystalline Integral Membrane
Protein Has Been Determined
Peripheral
Proteins Associate Reversibly with the Membrane
Membrane
Proteins Diff-use Laterally in the Bilayer
Membrane
Fusion Is Central to Many Biological Processes
Solute Transport
across Membranes
Passive
Transport Is Downhill Diffusion Facilitated by
Membrane Proteins
The
Glucose Permease of Erythrocytes Mediates Passive
Transport
Chloride
and Bicarbonate Are Cotransported across the
Erythrocyte Membrane
Active
Transport R,esults in Solute Movement against a
Concentration Gradient
Active
Cotransport of Na+ and K+ Is Energized by ATP
There Are
Three General Types of Transport ATPases
Ion
Gradients Provide the Energy for Secondary Active
Transport
Ion-Selective
Channels Act in Signal Transductions
Summary
Further Reading
Problem
