Search results
Results from the WOW.Com Content Network
Membrane lipids are a group of compounds (structurally similar to fats and oils) which form the lipid bilayer of the cell membrane. The three major classes of membrane lipids are phospholipids, glycolipids, and cholesterol. Lipids are amphiphilic: they have one end that is soluble in water ('polar') and an ending that is soluble in fat ...
Neural membranes contain several classes of glycerophospholipids which turnover at different rates with respect to their structure and localization in different cells and membranes. There are three major classes namely; 1-alkyl-2-acyl glycerophospholipid, 1,2-diacyl glycerophospholipid and plasmalogen.
In eukaryotes, cell membranes also contain another class of lipid, sterol, interspersed among the phospholipids. The combination provides fluidity in two dimensions combined with mechanical strength against rupture. Purified phospholipids are produced commercially and have found applications in nanotechnology and materials science. [3]
In some cases, the hydrated region can extend much further, for instance in lipids with a large protein or long sugar chain grafted to the head. One common example of such a modification in nature is the lipopolysaccharide coat on a bacterial outer membrane. [10] TEM image of a bacterium. The furry appearance on the outside is due to a coat of ...
Illustration of a eukaryotic cell membrane Comparison of a eukaryotic vs. a prokaryotic cell membrane. The cell membrane (also known as the plasma membrane or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of a cell from the outside environment (the extracellular space).
Biological lipids originate entirely or in part from two distinct types of biochemical subunits or "building-blocks": ketoacyl and isoprene groups. [3] Using this approach, lipids may be divided into eight categories: fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, and polyketides (derived from condensation of ...
Not all elements which are found in the human body in trace quantities play a role in life. Some of these elements are thought to be simple common contaminants without function (examples: caesium, titanium), while many others are thought to be active toxins, depending on amount (cadmium, mercury, lead, radioactives).
For lipids present in biological membranes, the hydrophilic head is from one of three classes: Glycolipids, whose heads contain an oligosaccharide with 1-15 saccharide residues. Phospholipids, whose heads contain a positively charged group that is linked to the tail by a negatively charged phosphate group. Sterols, whose heads contain a planar ...