CH 11 - Chapter 11 Membrane Structure Membranes are...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
9/18/09 1 Chapter 11 Membrane Structure Membranes are selective barriers
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
9/18/09 2 Membrane composition • Lipids Phospholipids (most abundant component) Glycolipids (sugar part of head group) Sterols (example: cholesterol) Amphipathic • Proteins Integral (directly attached to membrane) Peripheral (loosely associated with membrane) Fluid Mosaic Model of the cell membrane
Background image of page 2
9/18/09 3 Amphipathic phospholipids form a lipid bilayer A phospholipid bilayer will spontaneously rearrange to eliminate free edges. Not only does this favor repair of damage, but also the formation of a closed compartment. liposome
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
9/18/09 4 Liposomes (and vesicles) have a phospholipid bilayer and an aqueous interior Compare and contrast this structure with that of a micelle Membranes behave as a two-dimensional fluid Molecules Move Note: fluidity is not the same as flexibility (bending)
Background image of page 4
9/18/09 5 Factors affecting membrane fluidity • Phospholipid composition Fatty acid chain length (short chains fluidity) Fatty acid chain saturation (double bonds fluidity) • Sterols Cholesterol (more cholesterol fluidity) Adds rigidity The chain length and level of saturation determines the properties of fats Double bond causes bending
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
9/18/09 6 Cholesterol fills spaces in the bilayer
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/09/2010 for the course BIOL 213 taught by Professor Mcknight during the Spring '07 term at Texas A&M.

Page1 / 16

CH 11 - Chapter 11 Membrane Structure Membranes are...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online