Why do the ionized forms of the carboxyl and amino groups prevail in cells?
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damn! i should know this...i'm a science chem/bio student\n\ngimme some time...they are basic and acidic in nature. so in solution, there's the [H] ions for reaction in/around cells
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I think it's false. If the ionisation energy is increased, it's more difficult achieve ionisation, therefore less likely to be reactive. This is why those at the top of the group are more reactive.
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b)carboxylic acid and an amine
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amino acids.\n\nHere.  These people don't know jack.\n\nAbiotic Production of Organic Molecules\nThe classic experiment demonstrating the mechanisms by which inorganic elements could combine to form the precursors of organic chemicals was the 1950 experiment by Stanley Miller. He undertook experiments designed to find out how lightning--reproduced by repeated electric discharges--might have affected the primitive earth atmosphere. He discharged an electric spark into a mixture thought to resemble the primordial composition of the atmosphere. In a water receptacle, designed to model an ancient ocean, amino acids appeared. Amino acids are widely regarded as the building blocks of life.
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The word "amino" indicates the presence of the functional group in organic chemistry, the amino group, NH2.  The "acid" indicates the presence of the the functional group carboxylic acid (carboxyl) group (COOH).  Both functional groups are found in amino acids, hence the name.
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In biochemistry, denaturation is a structural change in biomolecules such as nucleic acids and proteins, such that they are no longer in their native state, and their shape which allows for optimal activity.\n\nThis change is usually caused by heat, acids, bases, detergents, alcohols, heavy metal salts, reducing agents or certain chemicals such as urea.\n\nContents [hide]\n1 Protein denaturation \n1.1 How denaturation occurs at levels of protein structure \n1.2 Loss of function \n1.3 Reversibility and irreversibility \n1.4 Some common examples \n2 Nucleic acid denaturation \n \n\n\n[edit]\nProtein denaturation\nProteins denature when they lose their three-dimensional structure - their chemical conformation and thus their characteristic folded structure. Proteins may be denatured at the secondary, tertiary and quaternary structural levels, but not at the primary structural level.\n\nProteins are long strands of amino acids linked together in specific sequences. A protein is created by ribosomes that "read" codons in the gene and assemble the requisite amino acid combination from the genetic instruction, in a process known as translation. The newly created protein strand then undergoes post-translational modification in which additional atoms or molecules are added, for example copper, zinc, iron. Once this post-translational modification process has been completed, the protein begins to fold (spontaneously, and sometimes with enzymatic assistance), curling up on itself so that hydrophobic elements of the protein are buried deep inside the structure and hydrophilic elements end up on the outside. The final shape of a protein determines how it interacts with its environment. If the shape of the protein is altered through some form of external stress (for example, by applying heat, acid or alkali) then it will no longer be able to carry out its cellular function. This is called denaturation of the protein.\n\nDenatured proteins can exhibit a wide range of characteristics, from loss of solubility to communal aggregation.\n\n[edit]\nHow denaturation occurs at levels of protein structure\nIn quaternary structure denaturation, protein sub-units are dissociated and/or the spatial arrangement of protein subunits is disrupted. \nTertiary structure denaturation involves the disruption of: \nCovalent interactions between amino acid side chains (such as disulfide bridges between cysteine groups) \nNoncovalent dipole-dipole interactions between polar amino acid side chains (and the surrounding solvent) \nVan der Waals (induced dipole) interactions between nonpolar amino acid side chains. \nIn secondary structure denaturation, proteins lose all regular repeating patterns such as alpha-helices and beta-pleated sheets, and adopt a random coil configuration. \nPrimary structure, such as the sequence of amino acids held together by covalent peptide bonds, is not disrupted by denaturation. \n[edit]\nLoss of function\nMost biological proteins lose their biological function when denatured, For example, enzymes lose their catalytic activity, because the substrates can no longer bind to the active site, and because amino acid residues involved in stabilizing substrates' transition states are no longer positioned to be able to do so.\n\n[edit]\nReversibility and irreversibility\nIn many proteins (unlike egg whites), denaturation is reversible (the proteins can regain their native state when the denaturing influence is removed). This was important historically, as it led to the notion that all the information needed for proteins to assume their native state was encoded in the primary structure of the protein, and hence in the DNA that codes for the protein.\n\n[edit]\nSome common examples\nWhen food is cooked, some of its proteins become denatured. This is why boiled eggs become hard and cooked meat becomes firm.\n\nA classic example of denaturing in proteins comes from egg whites, which are largely egg albumins in water. Fresh from the eg
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Just a clarification-DNA is composed of nucleic acids, not amino acids.  Amino acids are the building blocks of proteins.
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C\n\nthis is the definition of a strong acid.\n\nIt ionizes completely in water rather than entering into an equilibrium as a weak acid would do.
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the elements most likely to form ionic bonds have low ionization energies (such as the alkali metals and the alkaline earth metals, which form cations) or high electron affinities (such as halogens and oxygen, which form cations).
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the molecules the cell incorporates must be chemically modified to obtain Energy from them. In the first place a reaction occurs in the cytoplasm and then (for those organisms that perform respiration) inside the mitochondria some other reactions occur. The last ones are called respiration.
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They are just one electron away from achieving an octet.  So they require lower energy to lose this electron in a reaction.
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There r 20 amino acid,by combination of these amino acids diffirent proteins r formed.simple structure of a amino acidis like a central carbon atom(known as alpha carbon)to which a carboxilic group(-COOH) and a amine group(-NH2) and a side chain(-R group) attached,all amino acid have same structure but they differ to each other by side chain(-R group).
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First of all carboxylic acid  is a group.\n\nA carboxylic acid is an organic molecule with a -(C=O)-OH group. The group is also written as -COOH and is called a carboxyl group. The hydrogen on the -COOH group ionizes in water; carboxylic acids are weak acids. The simplest carboxylic acids are formic acid (H-COOH) and acetic acid (CH3-COOH).
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Basically what this is referring to is the ionization of the atoms you have listed. this occurs when there is a shift in the distribution of the electron in the various bands 'orbiting' the nucleus of the atom, or a proton has been added to the nucleus. \n\nWhat the statement seems to be refering to is the creation of a positive ion (cation). If this is to occur it needs a shift in the distribution of the electrons in the shells. To move an electron from one band to another, or to excite one enough to be lost fully from orbit you will need a level of energy. \n\nIn the cases stated, I would say that 3.1eV is the minimum energy required to create a transition of an electron between the bands or to lose an electron and so create the ion. \n\nHope that helps.
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Right-the classic idea is that somehow nucleotides got together to form a self-replicating molecule (odds are that it was RNA at first, not DNA), and then these self-replicating molecules began to assemble amino acid chains, which, through uncounted bazillions of reacions (keep in mind whole oceans full of molecules, and billions of years) these amino acid/peptides began to have specific  functions.  The newest theory is that proteins formed (which is fairly easy with the right conditions), and some of these were captured in small mycells (little balls of lipids, which form naturally).  In some of them, the proteins interacted with each other to produce energy-generating reactions, and perhaps served as templates for formation of more of the same protein.  We now know this is as least theoretically possible, because of prion diseases, in which small proteins get into cells and cause generation of the same protein chain, independently of the DNA coding mechanism.  So, under this theory, you have mycells full of enzymes, energy-generating ( as in glycolysis or the TCA cycle) and only later did RNA or DNA come to play a role, as a more convenient and stable way to code for the proteins.  This makes a lot of sense biochemically, and is easier to visualize chemcically than the classic theory.  And, it makes sort of an elegant and chemically poetic argument that the origin of life was the thing that really makes life today-the proteins and the protein reaction-and relegates DNA to just a convenient way for the proteins to replicate.
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The compounds have a high lattice enthalpy, thus much energy is required to break to ions up in solution. The also have very low solubility products, that is the product of the compounds ions in a saturated solution.
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a proton is positively charged and acts as nucleus in a hydrogen atom. let me first explain what is protonation.\nprotonation[prO´tunA´´shun] Pronunciation Key, in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a single proton. An example of protonation is the formation of the ammonium group NH4+ from ammonia, NH3. Protonation often occurs in the reaction of an acid with a base to form a salt (see acids and bases; salts). Protonation differs from hydrogenation in that during protonation a change in charge of the protonated species occurs, whereas the charge is unaffected during hydrogenation.\n\n The atom consists of a central, positively charged core, the nucleus, and negatively charged particles called electrons that are found in orbits around the nucleus.\n\nThe Nucleus\n\nAlmost the entire mass of the atom is concentrated in the nucleus, which occupies only a tiny fraction of the atom's volume. The nucleus of an atom consists of neutrons and protons, the neutron being an uncharged particlarticlelinks" href="/encyclopedia/P/proton.html">proton a positively charged one. Their masses are almost equal. Atoms containing the same number of protons but different numbers of neutrons represent different forms, or isotopes, of the same element.\n\nfor more information i will tell u more about electrons.\nSurrounding the nucleus of an atom are its electrons; for a neutral atom, the number of electrons is equal to the atomic number. The outermost electrons of an atom determine its chemical and electrical properties. An atom may combine chemically with another atom in various ways, eieceiving electrons, thus setting up an electrical attraction between the atoms (see ion), or by sharing one or more pairs of electrons (see chemical bond). Because metals have few outermost electrons and tend to give them up easily, they are good conductors of electricity or heat (see conduction).\n\nThe electrons are often described as revolving about the nucleus as the planets revolve about the sun. This picture, however, is misleading. The quantum theory has shown that all particles in motion also have certain wave properties. For a particle the size of an electron, these properties are of considerable importance. As a result the electrons in an atom cannot be pictured as localized in space, but rather should be viewed as smeared out over the entire orbit so that they form a cloud of charge. The electron clouds around the nucleus represent regions in which the electrons are most likely to be found. The shapes of these clouds can be very complex, in marked contrast to the simple elliptical orbits of planets. Surprisingly, the sizes of all atoms are comparable, in spite of the large differences in the number of electrons they contain.\n\ni hope u find my information sufficient.