what types of chemical linkages are found in a typical phosphatidyl phospholipid(such as PC)?
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Phosphatidylcholine has ester bonds and phosphate esters.  There is also a terminal trimethylammonium residue
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Calcium phosphate is Ca3(PO4)2.  Phosphorus trichloride is PCl3.  Determine the molecular weight of each and then figure out how much of that weight comes from phosphorus.\n\nUsing approximate atomic masses,\n\nCa3(PO4)2 = 3*40 + 2*31 + 8*16 = 310; %P = 62/310 = 20%\n\nPCl3 = 31 + 3*35.5 = 137.5; %P = 31/137.5 = 22.5%
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Some do....Some consist completely of single bonds between the carbon atom but some have double bonds reducing the number of hydrogens that are present. \n\nMolecules without those double bonds are called saturated.  \nMolecules with those double bonds are called unsaturated.  \nMolecules with more than one of those double bonds are called polyunsaturated. \n\nThe difference between these molecules is this. Stearic acid has all single bonds. It is saturated and any fat made just from stearic acid will be a saturated fat. The other three have at least one C-to-C double bond. They are unsaturated and any fat (or oil) made from them will be unsaturated. Fats made from linoleic acid and/or linolenic acid have the added distinction of being polyunsaturated fats or oils because they have more than one double bond.
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# Large molecules in biological systems namely proteins, nucleic acids, and polysaccharides.\nwww.whatislife.com/glossary.htm\n\n# large single chemical entities such as pieces of DNA or RNA.\nwww.biologylessons.sdsu.edu/classes/lab3/glossary.html\n\n# A macromolecule is a molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass.\nen.wikipedia.org/wiki/Macromolecule\n\nA macromolecule is a molecule with a large molecular mass, but generally the use of the term is restricted to polymers and molecules which structurally include polymers. [1]\n\nMany examples come from biology and in particular biochemistry. These include proteins, starches, lipids and nucleic acids (such as DNA), which are sometimes called "biomacromolecules" or biopolymers. Synthetic examples include plastics. The integral domains of crystals and metals, while composed of very large numbers of atoms joined by molecule-like bonds, are rarely referred to as "macromolecules."\n\nThe term macromolecule is also sometimes used to refer to aggregates of two or more macromolecules held together by intermolecular forces rather than by chemical "bonds". This usage is common in particular when the individual macromolecules involved aggregate or "assemble" spontaneously and rarely exist in isolation. Such an aggregate is more properly called a macromolecular complex. In such a context, individual macromolecules are often referred to as subunits (see e.g. protein subunit).\n\nSubstances that are composed of macromolecules often have unusual physical properties. The properties of liquid crystals and such elastomers as rubber are examples. Although too small to see, individual pieces of DNA in solution can be broken in two simply by suctioning the solution through an ordinary straw. This is not true of smaller molecules. The 1964 edition of Linus Pauling's College Chemistry asserted that DNA in nature is never longer than about 5000 base pairs. This is because biochemists were inadvertently and with perfect consistency breaking their samples into pieces. In fact, the DNA of chromosomes can be tens of millions of base pairs long.\n\nAnother common macromolecular property that does not characterize smaller molecules is the need for assistance in dissolving into solution. Many require salts or particular ions to dissolve in water. Proteins will denature if the solute concentration of their solution is too high or too low.
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Many lipids are glycolipids - a lipid bound to a carbohydrate.  These are often components of cell membranes.
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A polymer is a a bunch ("poly") of chemically bonded chain members ("mers")\n\nA very common example is polyethylene, in which the mer is ethylene:\n\nCH2=CH2   ----> [-CH2-CH2-]n\n\nThis results in a linear chain.\n\nAn appropriate mer for polymerization must have some kind of way to bond to at least two other mers.  A double bond can be opened to form bonds with two other things.  Carboxylic acids can form bonds with alcohols and amines to form ester or amide linkages.\n\nIf you have the ability to form MORE than 2 bonds with other mers, you have the ability to form a crosslinked polymer (sometimes called a network polymer)\n\nFor example, if you have a di-acid molecule, it could form a polymer with a di-alcohol.  If you use glycerol as your alcohol (glycerol has 3 alcohol groups instead of 2) you can form a cross-linked network polymer.\n\nAnother way to form a crosslinked polymer is if useful chemistry remains in the polymer after the polymerization reaction.  For example, butadiene has two double bonds in it, and after the polymerization reaction, it still has one double bond per mer unit in the chain.  If you add sulfur to the polymer and heat it up, the sulfur can react with the existing double bonds to form disulfide bridges that connect two chains together--these are called cross-links.\n\nThe vulcanization of rubber is an example of chemically crosslinking a polymer (butadiene is chemically similar to rubber).  Tires are made out of this rubber.\n\nCross links provide a mechanical limitation on the stretchability of polymers.  Normally, a polymer can be stretched slowly because over time the chains can slide past each other (like pulling apart noodles from a pot of cooked spaghetti).  Cross links prevent the noodles from sliding past each other because all the noodles are mechanically bonded to each other at a few places.
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Liposomes are composed of a lipid bilayer separating an aqueous internal compartment from the bulk aqueous phase. Micelles are closed lipid monolayers with a fatty acid core and polar surface, or polar core with fatty acids on the surface (inverted micelle).
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amino acids, lipids, carbohydrates, and nucleic acids.  Biomolecules means they are generally found only in biological systems, though they can be found in very small amounts in abiotic systems.  lipids (fats, etc) and carbohydrates (starches, etc) can be composed of only carbon, hydrogen, and oxygen.  Amino acids (which make proteins) and nucleic acids (which make DNA and RNA) are composed of oxygen, carbon, hydrogen, and nitrogen.  But, there are elements, not biomolecules.  Just as a note, some amino acids also have sulpher, phosphorus, and other elements, and nucleic acids contain phosphorus.
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the P has three bonds and all the Cl's have 4 bonds
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D - definitely all of these:\n\nA - TRUE: liposomes are shaped like a donut, in which the membrane is a lipid bilayer\nB - TRUE: by definition, liposomes contain an aqueous core; if the core is empty, they are called micelles\nC - TRUE: The heads are hydrophilic, the tails are hydrophobic.
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Polymer is a generic term used to describe a very long molecule consisting of structural units and repeating units connected by covalent chemical bonds.  The key feature that distinguishes polymers from other molecules is the repetition of many identical, similar, or complementary molecular subunits in these chains. These subunits, the monomers, are small molecules of low to moderate molecular weight, and are linked to each other during a chemical reaction called polymerization.
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The lipid parts have a cation binding site to bind with the negative charges of the DNA.  The final complex is called a liposome.  \n\nIt then carries the DNA into cell and into the nucleus.  You still have to use a bunch of reagents in the process.  This is just from my research background.  The specifics are long.  You can email me for them
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cross linked poly ethylene
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Centrioles.\n\nNucleic acid.\n\nCell membrane is found in both animals and plants but cell wall is found only in plants. Cell wall is made up of cellulose (carbohydrates), while cell membrane is made up of lipids. Cell wall does not regulate the movement of substances in and out of it, but cell membrane does.
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All biological membranes, including the plasma membrane and the internal membranes of eucaryotic cells, have a common overall structure, they are assemblies of lipid and protein molecules held together by noncovalen interactions. The Lipid molecules are arranged as a continuous double layer 4 to 5 nm thick. This lipid bilayer provides the basic structure of the membrane and serves as a relatively impermeable barrier to the flow of most water- soluble molecules.The proteins molecules are dissolved in the lipid by layer.
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www.visionlearning.com/library/module_viewer.php?mid=55 - 66k \n\nwww.biology.arizona.edu/biochemistry/ tutorials/chemistry/page2.html - 7k - \n\nhttp://en.wikipedia.org/wiki/Chemical_bond
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Fats are entirely polar substances, and do not dissolve in water.  They are composed of Carbon, Hydrogen and Oxygen.\nFats are used in protection, storage and keeping the organism warm.\n\nPhospholipids have phosphorous groups attatched, and have one polar and one non polar end.  (One water loving end that can "dissolve" in water, and one end that hates water.)\nPhospholipids are found the phospholipid bilayer of the cell membrane and are used to seperate the cell from it's environment, as well as letting some things in while keeping others out.\n\nHope that helped.