Search results
Results from the WOW.Com Content Network
Cholesterol is the principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils. [3] [4]Cholesterol is biosynthesized by all animal cells [citation needed] and is an essential structural and signaling component of animal cell membranes.
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 ...
Cholesterol regulates the function of several membrane proteins associated with lipid rafts. It does so by controlling the formation or depletion of lipid rafts in the plasma membrane. The lipid rafts house the membrane proteins and forming or depleting the lipid rafts moves the proteins in or out of the raft environment, thereby exposing them ...
Sterols and related compounds play essential roles in the physiology of eukaryotic organisms, and are essential for normal physiology of plants, animals, and fungi. [4] For example, cholesterol forms part of the cellular membrane in animals, where it affects the cell membrane's fluidity and serves as secondary messenger in developmental signaling.
7-Dehydrocholesterol (7-DHC) is a zoosterol that functions in the serum as a cholesterol precursor, and is photochemically converted to vitamin D 3 in the skin, therefore functioning as provitamin-D 3. The presence of this compound in human skin enables humans to manufacture vitamin D 3 (cholecalciferol).
A biological membrane is a form of lamellar phase lipid bilayer. The formation of lipid bilayers is an energetically preferred process when the glycerophospholipids described above are in an aqueous environment. [2]: 333–4 This is known as the hydrophobic effect.
Cholesterol is the dynamic "glue" that holds the raft together. [3] Due to the rigid nature of the sterol group, cholesterol partitions preferentially into the lipid rafts where acyl chains of the lipids tend to be more rigid and in a less fluid state. [6] One important property of membrane lipids is their amphipathic character.
In animals, these fats are obtained from food and are synthesized by the liver. [1] Lipogenesis is the process of synthesizing these fats. [2] [3] The majority of lipids found in the human body from ingesting food are triglycerides and cholesterol. [4] Other types of lipids found in the body are fatty acids and membrane lipids.