eChapter Name: Biological Membrane and Function
9789389907599
eBook Name: BIOCHEMISTRY,MOLECULAR BIOLOGY AND BIOTECHNOLOGY: INSTANT NOTES
by Parmod P. Mahulikar, Shama M.Chavan, H.P. Gajera
COMMON FEATURES OF BIOLOGICAL MEMBRANES
Membranes are sheetlike, just a few molecules thick and form closed boundaries between cell compartments.
Membranes contain lipids and proteins, with small amounts of carbohydrayes linked to the lipids and proteins.
Lipids in membranes are small with hydrophobic and hydrophilic portions. Lipid bilayers provide a barrier to the diffusion of polar molecules.
Characteristic functions of membranes are mediated by specific proteins, serving as pumps, channels, receptors, energy transducers and enzymes.
Membrane components associate through noncovalent interactions.
Membranes are asymmetrical, with two sides of the membrane differing from each other.
Lipid and protein molecules often diffuse rapidly in the plane of the membrane.
Central transport of ions and molecules into and out of the cell.
Generate proton gradients for ATP production by oxidative phosphorylation.
Receptors bind extracellular signals and transduce the signal to cell interior.