What is a cell membrane?
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Each cell is like a plastic bag filled with a spaghetti soup of all the different cell components. But it's a very special plastic bag, because it is permeable - water and friendly chemicals can pass through it, but bad guys get shut out. Rather like the firewall works (or should work!) when you're on the internet. The cell membrane is the plastic of the bag.\n\n:-)\nDC\nwww.tigerworld.tv
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Okay this is a bit of a complicated question, but i'll do my best, in short these are really very different things.\n\nFirst cell membranes are found in all cells (animal, plant, fungi etc.) they are made up of lipids, generally as a bilayer.  take the membrane from around the outside of a eukaryotic cell, its formed from phospolipids - these molecules have a hydrophilic head [ie will disolve in water/ has a charge] (the phosphate bit) and a hydrophobic tail (the lipid (fat) bit). The hydrophobic bits stick together and the hydrophilic bits are open to the solution on each side (search "lipid bilayer" with yahoo! Images if you want a diagram:-) ).  The outer cell membrane is forming a barrier between the inside and outside of the cell, alowing the cell to control the movment of molecules into and out of itself.  There are a lot of other membranes in the cell apart from the outher cell membrane, the endoplasmic reticulum for example is basicly made up of membrane.\n\nThe cell wall on the other hand isn't present in all cells (we humans (along with all other animals) don't get one). The cell wall is present on the extracellular side of the outer cell membrane.  it is hard and ridgid (unlike the membrane that is fluid) it is made up of lond polymers, and serves to protect the cell.  Plant cell walls are made up of mainly cellulose (in fact when you look at a peice of wood all you are really seeing is the leftover cell walls, and the rest of the cell has long gone).  Fungi also have cell walls but this time not made of cellulose but instead made of chitin, the cell wall still serves the same role however.\n\nIn short the membrane lets the cell control what goes in and out,  and the cell wall provides rigidity.  Membranes are made of lipids (fats) and cell walls of long polemers like chitin and cellulose.\n\nI hope this helps to answer your question, and look for some diagrams - it will make it a lot easier.
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cells dont have cells but they they have organelles which are sort of like cells, which includes mitochondria, ribosomes, golgi apparatus, etc. that have various functions such as converting sugar to energy, synthesizing proteins, etc. they're sort of like minature organs if the cell was your body (hence the name organelles
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The most important feature distinguishing the cells of plants from those of animals is the cell wall. In plants this wall protects the cellular contents and limits cell size. It also has important structural and physiological roles in the life of the plant, being involved in transport, absorption, and secretion.
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1)  The cell is the unit of structure, physiology, and organization in living things. \n   2)  The cell retains a dual existence as a distinct entity and a building block in the   construction of organisms. \n   3)  Cells form by free-cell formation, similar to the formation of crystals (spontaneous generation).\n\nKeep this as hint and do your homework
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All human tissue and body parts are made of cells. They are the building blocks of all living creatures.
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plasma membrane-bouncer or security\ncell wall-Berlin Wall\nmitochondria-power plant\nER-Ups of the cell\nlysosome-decomposers\nvacuole-water and septic tank\nchloroplast-dye
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As the name implies it is outer thin layer of a LIVING cell.In plant cells in addition to the cell membrane there is a cell wall,either of cellulose or lignin,which is the external most, protective covering.The cell membrane controls the entry and exits of molecules in side the LIVING cell from out side.The cell wall provides protection and gives shape to the cell, both living as well as dead.What we call wood is a collection of billions of dead plants cells that have strong lignified walls.\nAnimal cells lack a proper cell wall.\nOne can easily see a cell membrane with naked eyes. Take a hard boiled poultry egg. Gently crack and remove the outer SHELL which  is of calcium carbonate.Just on its inner side and coverig the WHITE of the egg ( which is now hard and firm) one is sure to find an extermely thin membrane.That is the CELL MEMBRANE! One can see it in afresh egg as well but for a first timer boiled egg is easier. Cell membrane is also called PLASMA MEMBRANE, as it forms the outer limits of the living cytoplasm of a cell.\nThe information above will make one believe that an egg is a cell. Yes it is true in all its aspects. It IS a CELL and since it has to survive out side the animal body, it is provided with a shell which is not a part of the cell.Poultry egg, or for that matter any egg is a cell. An ostrich's egg is the largest cell of all!.
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Nuclear?  Nuclear envelope?  Nuclear membrane? \n\nThe word 'eukaryote' means 'true nuclei'.  They are talking about the membrane which surrounds the nucleus of the cell.  This is not present in Prokaryotes.
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Cell membranes are made of lipid bilayers, meaning it is made of a type of fat.  KOH is a strong base that is capable of reacting with the fat in the same reaction that produces soap.  This destroys the lipid bilayer
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Cell membrane, or phospholipid bi-layer.
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permeability of the cell membrane
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Protein along with lipids form a lipoproteinous wall that surrounds the cell which is called plasma-membrane.for details got to below given link:\nhttp://en.wikipedia.org/wiki/Plasma_membrane
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Endocytosis is when a cell takes outside material inside it.  The cell membrane is a phospholipid bilayer.  This means that that outer and inner surfaces of the memberane like to be with water and the center of the memberane likes to be with oil.    The cell membrane deforms to surround whatever it is trying to bring into the cell.  The membrance then closes around the stuff that it is engulfing.  At this point the cell is still completely surrounded by the membrane; however, there is a new, smaller membrane bound pocket inside of the cell.  That is endocytosis.  If the endocytosis is pH dependent, that means that this cellular process happens in a manner that is related to how acidic or basic the outside enviroment is.\n\nThis question might get a more detailed answer in the biology catagory.
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The cell membrane is a lipid bilayer made from phospholipids.  As a lipid, it is permeable to other lipids (e.g. steroid hormones) but not to polar molecules (e.g. potassium or glucose).  Polar molecules require various types of membrane proteins (e.g. potassium channels) or endocytosis (glucose) for absorption into the cell.  \n\nHope this is helpful for you.  Best wishes and good luck.
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an electrical wave that travels down the membrane of a cell
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Human cells and animal cells are very similar. Actually, human cells are types of animal cells. Every different tissue in your body is made up of different kinds of cells. They may have different structures, especially in their cell membrane, which make the function of that cell different. Therefore they do have similar functions, depending on their structure and characters.