okay ill be serous on this one. lipids are hydrophobic which means that they are afraid of water. in order for a lipid to bond with a membrane it has to double up with other lipids forming a bilayer because the tails are hydrophobic. so heads are out and tails are in.
The lipid bilayer is a thin membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around cells. The cell membrane of almost all living organisms and many viruses are made of a lipid bilayer, as are the membranes surrounding the cell nucleus and other sub-cellular structures. The lipid bilayer is the barrier that keeps ions, proteins and other molecules where they are needed and prevents them from diffusing into areas where they should not be. Lipid bilayers are ideally suited to this role because, even though they are only a few nanometers thick, they are impermeable to most water-soluble (hydrophilic) molecules. Bilayers are particularly impermeable to ions, which allows cells to regulate salt concentrations and pH by pumping ions across their membranes using proteins called ion pumps.
Natural bilayers are usually made mostly of phospholipids, which have a hydrophilic head and two hydrophobic tails. When phospholipids are exposed to water, they arrange themselves into a two-layered sheet (a bilayer) with all of their tails pointing toward the center of the sheet. The center of this bilayer contains almost no water and also excludes molecules like sugars or salts that dissolve in water but not in oil. This assembly process is similar to the coalescing of oil droplets in water and is driven by the same force, called the hydrophobic effect. Because lipid bilayers are quite fragile and are so thin that they are invisible in a traditional microscope, bilayers are very challenging to study. Experiments on bilayers often require advanced techniques like electron microscopy and atomic force microscopy.
Phospholipids with certain head groups can alter the surface chemistry of a bilayer and can, for example, mark a cell for destruction by the immune system. Lipid tails can also affect membrane properties, for instance by determining the phase of the bilayer. The bilayer can adopt a solid gel phase state at lower temperatures but undergo phase transition to a fluid state at higher temperatures. The packing of lipids within the bilayer also affects its mechanical properties, including its resistance to stretching and bending. Many of these properties have been studied with the use of artificial "model" bilayers produced in a lab. Vesicles made by model bilayers have also been used clinically to deliver drugs.
Biological membranes typically include several types of lipids other than phospholipids. A particularly important example in animal cells is cholesterol, which helps strengthen the bilayer and decrease its permeability. Cholesterol also helps regulate the activity of certain integral membrane proteins. Integral membrane proteins function when incorporated into a lipid bilayer. Because bilayers define the boundaries of the cell and its compartments, these membrane proteins are involved in many intra- and inter-cellular signaling processes. Certain kinds of membrane proteins are involved in the process of fusing two bilayers together. This fusion allows the joining of two distinct structures as in the fertilization of an egg by sperm or the entry of a virus into a cell.
The cells is what supports on one thing. The one thing that the cell supports is the lipid bilayer.
well as you can see, the lipid bilayer has many parts to its related environment
A lipid bi-layer is a thin membrane of an animal or plant cell that comprises of two layers of lipid molecules. It is also known as the phospholipid bilayer.
Lipid Bilayer
cell membrane
It depends on which lipid bilayer you're talking about. There is the phospholipid bilayer that surrounds eukaryotic cells, cholesterol phospholipid bilayers, protein lipid bilayers, phase transition lipid bilayer, lipid bilayer membrane...
The nucleus has the same sort of boundary as the cell itself has. That is a lipid bilayer.
The cells is what supports on one thing. The one thing that the cell supports is the lipid bilayer.
The lipid bilayer is impermeable to large molecules and small polar molecules. Only water and gas can easily pass through the bilayer.
well as you can see, the lipid bilayer has many parts to its related environment
H. Ti Tien has written: 'Planar bilayer lipid membranes (Progress in surface science)' 'Bilayer lipid membranes (BLM)' -- subject(s): Bilayer lipid membranes
A lipid bilayer is characteristic of all biological membranes. Some membranes are double bilayers.
lipid bilayer
A lipid bilayer is a very thin layer that is in between lipid molecules. It is about as think as a piece of paper and can be as large as it needs to be to contain the necessary cells.
A lipid bi-layer is a thin membrane of an animal or plant cell that comprises of two layers of lipid molecules. It is also known as the phospholipid bilayer.
60%phospholipids and 30% proteins and10% carbohydrates
The nuclear envelope is another name for the lipid bilayer around the nucleus of the cell.