Search results
Results from the WOW.Com Content Network
Lipids are a broad group of organic compounds which include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing energy, signaling , and acting as structural components of cell membranes .
Lipids (oleaginous) are chiefly fatty acid esters, and are the basic building blocks of biological membranes. Another biological role is energy storage (e.g., triglycerides). Most lipids consist of a polar or hydrophilic head (typically glycerol) and one to three non polar or hydrophobic fatty acid tails, and therefore they are amphiphilic.
Lipids unlike the other macromolecules, lipids are not defined by chemical Structure. Lipids are any organic nonpolar molecule. Some lipids are held together by ester bonds; some are huge aggregates of small molecules held together by hydrophobic interactions. Carbohydrates carbon, hydrogen, and oxygen Major protein Complexes?
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 ...
All polymers are made of repetitive units called monomers. Biopolymers often have a well-defined structure, though this is not a defining characteristic (example: lignocellulose ): The exact chemical composition and the sequence in which these units are arranged is called the primary structure , in the case of proteins.
Carbohydrates include monomers and polymers of sugars. [38] Lipids are the only class of macromolecules that are not made up of polymers. They include steroids, phospholipids, and fats, [37] largely nonpolar and hydrophobic (water-repelling) substances. [39] Proteins are the most diverse of the macromolecules.
In the top image the lipids have not rearranged, so the pore wall is hydrophobic. In the bottom image some of the lipid heads have bent over, so the pore wall is hydrophilic. For cellular organisms, the transport of specific molecules across compartmentalizing membrane barriers is essential in order to exchange content with their environment ...
A polymer (/ ˈ p ɒ l ɪ m ər / [4] [5]) is a substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeating subunits derived from one or more species of monomers. [6]