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c-value: a quantitative parameter introduced as part of the AI Hypothesis Rigorously
defined elsewhere (see text), it is to a first approximation the electron density of the singly
charged oxygen atom of an oxyacid group represents the electronic variable underlying the different acid dissociation
constants or pK values. Weak acid with high pK has a higher c-value; strong acid with low pK has a lower c-value.
c'-value: counterpart for the c-value but applicable to cationic sites High c'-value denotes strong positive charge; low c'-value denotes low positive charge.
c-value analogue: a parameter which measures the electron density of the carbonyl oxygen atom of
a polypeptide chain or protein.
c'-value analogue: a parameter which measures the positive charge density of the imino group of a polypeptide chain or protein.
Ca2+ Ca++: calcium ion.
capillary condensation: condensation of gaseous molecules as normal liquid in narrow pores.
carbodiimide: a carboxyl reagent, which combines and destroys carboxyl groups.
carbohydrate: any of the neutral compounds of carbon, hydrogen and oxygen like sugars and starch, much of which are formed by green plants and make up a major class of animal foods.
carbonyl group: a bivalent radical CO occurring in the peptide group (CONH) of protein backbones and in simpler molecules including aldehydes, ketone, carboxylic acids and amides.
carbonyl oxygen: the oxygen atom belonging to a carbonyl group (CO).
carboxyl group: a univalent radical (COOH) typical of organic acids (See also
β- and γ-carboxyl groups).
carboxyl group specific reagent: a chemical reagent, which has a specific affinity for, and hence
focused destructive power for the carboxyl group.
cardiac glycosides: Cardiac glycosides are complex steroids with one or more carbohydrate residues attached through the oxygen atom at position 3 of the steroid nucleus. Cardiac glycosides like digitalis increases the force
of myocardial contraction without concomitant increase in the heart's oxygen consumption. The highly water-soluble ouabain is a cardiac glycosides much studied by cell physiologists for its control of the
K+ and Na+ accumulation in living cells.
cardinal adsorbent: an adsorbent on a cell protein that critically control the metastable cooperative state of a gang of protein sites.
cardinal site: a locus on a protein composed of one or more closely placed side chain and/or backbone functional groups that critically control the metastable cooperative state of a gang of interacting neighboring sites.
carrier theory: a theory that traffic of a substance between the inside of a cell and its surrounding medium is mediated by a complex molecule, which shuttles back and forth transporting its molecular passengers.
catalyze: to bring about the acceleration of a chemical reaction by a substance (catalyst), which itself remains unchanged at the end of the reaction.
cause vitae: the underlying cause of life As used by believers in vitalism,
cause vitae is not only unknown but also unknowable.
cell membrane: In the textbook version of the membrane theory or its variant the membrane-pump theory, each living cell is covered with a bilayer of phospholipids, in which islets of fully submerged or partially submerged proteins molecules are imbedded. (For an updated version based on the AIH, see Chapter
13.)
cell physiology: the scientific study of the functions of living cells.
cell theory: the theory, formally introduced by Theodor Schwann in 1839, that all living organisms are made of (as a rule) tiny units called cells.
cellular electrical potentials: See resting potential and action potential.
cellulose acetate membrane: a thin water-loaded translucent membrane manufactured from cellulose acetate and marketed by Eastman Kodak Co., Rochester. Before use, the membrane is heated at 90°
C for half an hour to "activate" and make it more selective in its differential permeability toward solute molecules.
center(s) of activity of a drug molecule: the idea that a drug molecule may possess more than one center or point of (effective and functional) attachment to a receptor site.
central canal: a narrow passage going through the center of the spinal cord.
central vacuole: the large sap-filled space inside mature plant cells (see Fig. 1A).
centrifugation method, Ling-Walton centrifugation method: a simple and rapid method introduced by G. N. Ling and C. Walton in 1975 to remove quantitatively the extracellular fluid of the sartorius or isolated muscle-fiber bundles by spinning the muscle in a hermetically sealed packet at 1000 g. for 4 minutes.
cetyltrimethylammonium bromide: a cationic detergent containing a long chain quaternary ammonium ion.
CG electrode: (oxidized) collodion-coated glass electrode.
Characea: the family of giant algae found in fresh water ponds including
Chara and Nitella.
"charge reversal": a phenomenon extensively studied by Bungenberg de Jong. If in a steady DC electric field, the migration of, say, a negatively-charged colloid particle toward the positively charged electrode reverses its direction of migration when a salt (X+Y-) is introduced, it would suggest that an excess
of X+ has been taken up by the colloid.
chelate: (chela, a pincer-like organ or claw from Grk. chele, claw) of, or relating to, or having a ring-like structure that usually contains a metal ion held by coordination bonds.
Chiang-Tai's inductive index: On the surface, Chiang-Tai inductive index resembles other inductive constants introduced earlier (Hammett's inductive constant,
σ; Taft's inductive constants,
σI) in that it too offers a list of numerical values expressing the relative inductive power of various atomic and group substituent. However, here is where the similarity ends. All prior inductive constants were entirely empirical in origin and therefore limited to substituents on which published data are available. In contrast, M. C. Chiang and T.C. Tai have offered theoretical formulae, which enable the computation of inductive indices for new substituents never published before. Without Chiang and Tai's work, the study summarized in Table 4, for example, would be difficult if not impossible to complete. (For details of this important work, see Ref. 509).
chloroform: CHCl3, a colorless volatile heavy liquid used as a solvent or general anesthetic.
chloroacetic acid (monochloroacetic acid): ClCH2COOH, colorless, white, deliquescent crystals See dichloroacetic acid.
Clark's theory of drug action: proposed by A.J. Clark in 1927, in which the intensity of drug action is directly proportional to the concentration of the drug-receptor complex.
close-contact adsorption: adsorption in which the adsorbed entity and the adsorption site are in close direct physical contact.
close-contact surface adsorption (CSA) potential: a theory of resting (and action) potential of living cells and model systems (e.g., glass electrode, or CO electrode) in which the electric potential difference originates from the presence of fixed anionic sites at the cell or model surface and countercations adsorbed on these sites in a close-contact manner First introduced by G. N. Ling in 1955 and 1959, it had been until recently described simply as a surface adsorption (SA) potential.
CO group: usually refers to carbonyl groups on the polypeptide chain (-COCHRNH-)n.
coacervate: Under the right condition (e.g., elevated temperature, addition of salts, gum arabic) a solution of a certain colloid by itself or in conjunction with other polar macromolecules separates out from a colloid-poor phase. This colloid-rich phase was named coacervate and the phenomenon as coacervation by H. G. Bungenberg de Jong and H. R. Kruyt in 1929.
coacervation: the process that leads to the formation of coacervate (see coacervate) It involves the separation of a single homogeneous aqueous solution into two phases with a clear boundary between them.
coefficient of proportionality: A.S. Troshin's name for what is called
distribution ratio in the Berthelot-Nemst distribution law or the
equilibrium distribution coefficient or q-value in the AI Hypothesis See
Berthelot-Nernst distribution law, and/or q-value.
Collander and Bärlund's lipoidal filtration
theory: a theory of the makeup of cell membranes proposed in 1933 by R. Collander and H.
Bärlund, in which the
continuous
phase of the cell membranes is lipoidal, punctured by small pores that act as molecular sieves allowing the passage of small solutes but not that of larger ones.
collodion membrane: Collodion is the name of a solution of 4 g. of pyroxylin (largely nitrocellulose) in a mixture of one part ethyl alcohol and one part ether. By casting collodion on the surface of a glass test tube, soaking it in water, a thimble of collodion membrane is formed.
collodion membrane bearing carboxyl groups: Pure collodion does not carry carboxyl groups. However, either as an impurity or added deliberately by oxidation, collodion membranes bearing carboxyl groups can be obtained.
colloid: a term introduced by Thomas Graham in 1861 from the Greek word for glue or gelatin as representing substances like gelatin that diffuse slowly and do not form crystal In years following colloid became entangled with the word macromolecule and lost its identity until a new and simple definition was given by G. N. Ling {see [11.3(2)]}.
colloid chemistry: scientific study aimed at the elucidation of the properties and behaviors of colloids and the colloidal condition.
competitive inhibition: a term introduced by enzyme chemists to describe the lowering of the rate of enzyme activity by a substance, which competes against the substrate for the enzyme site In recent years, the terms has been broadened to describe similar competitive inhibition in the effectiveness of drug action, the rate of permeation of ions and in the selective adsorption of solutes, for example.
complex coacervate: coacervate the formation of which involves the formation of salt-linkages among its macromolecular components.
complexions, Ω: the number of equally probable micromolecular states of the assembly The number of equally probable micromolecular states is determined by the number of particles in the assembly, the total energy they share and the quantum-mechanically allowed energy levels. (For a simple additional exposition, see Ref. 98 pp 4-12).
compound microscope: a microscope consisting of an objective lens and an eye piece mounted in a drawtube.
concentration gradient: Gradient means slope; a concentration gradient means a slope in the concentration of a substance starting out high in one phase and ending low in an adjoining phase.
condenser: For storing electric charge, a device consisting of two metal plates separated by air as an insulator is called a condenser.
conductance: the reciprocal of the resistance of a substance, a solution or circuit to the passage of a current.
congruous anion: an anion which for steric, electronic or other reason(s) is preferentially adsorbed by the fixed cations in the protoplasm of a specific type of living cell at rest.
CONH group: the group known as the "peptide linkage".
contractile proteins: A protein which under specified conditions, contracts reversibly is often referred to as contractile protein, usually referring to the actin-myosin system.
converging double reciprocal plot: See reciprocal plot.
cooperative phenomenon: Ralph Fowler first used the term "cooperative transitions" to describe changes of state of a system, in which the interaction among individual atoms or molecules tends to increase in importance with the progress of the change under consideration. This type of cooperative phenomenon cannot be understood in terms of the properties of individual constituent atoms or molecules alone, but is the result of, and therefore can be explained in terms of their interaction.
cooperative adsorption-desorption pump: a theoretical model proposed by G. N. Ling first in 1965, in which all-or-none type of autocooperative adsorption and desorption play central roles in the active transport or pumping of ions and solutes across bifacial cell layers.
cooperative assembly: A collection of atoms and molecules being in close contact with one another are engaged in cooperative interaction among them so that the entire assembly acquires properties beyond the summation of the properties of isolated individual components.
cooperatively linked: Entities that are cooperatively linked are engaged in near-neighbor interaction among themselves.
cooperatively linked protein-ion-water system: a system of proteins, ions and water in close association and linked to one another in a cooperative manner.
copper ferrocyanide: red-brown water-insoluble crystals formed when copper sulfate is mixed with potassium ferrocyanide.
copper sulfate: usually refers to the cupric salt, either anhydrous or with 5 water of hydration. It is readily soluble in water, forming a blue solution.
Corning 015 glass: a glass manufactured by Corning Co. for making good pH electrodes. It shows high specificity for the
H+ and little or no sensitivity to interfering ions like K+ or
Na+ for example.
Coulombic energy: electrostatic interaction energy between charged entities, equal in magnitude to the product of the charges of each entity divided by the product of the distance between them and the dielectric constant.
counter-cation, counter-ion: As a result of the Law of Macroscopic Neutrality, fixed (negatively—charged) anions are as a rule accompanied by an equal number of ions of the opposite electric charge. These counter-ions are in the form of
counter-cations, if the fixed ions are negatively charged.
counter-ion: See counter-cation.
covalent bond: a type of chemical bond resulting from the sharing of electrons between two atoms.
creatine kinase: an enzyme that catalyzes the reversible transfer of a phosphate group from a creatine phosphate molecules to an ADP molecule, forming creatine and ATP or the converse.
creatine phosphate (CrP), phosphocreatine: Found in high concentration in muscle cells, it is also the major congruous anion of this cell type. Through the action of the enzyme, creatine kinase, CrP acts as a reservoir of the terminal phosphate for the resynthesis of the principal cardinal adsorbent, ATP, when it is hydrolyzed.
crevice hypothesis: an once-popular hypothesis to explain the peculiar S-shaped oxygen binding curves of hemoglobin. In this hypothesis, heme sites with strong binding energy for oxygen are buried inside "crevices" inaccessible to oxygen until the "crevices" are somehow pried open by the binding of oxygen onto weaker oxygen-binding heme sites on the surface of the hemoglobin molecules. Complete elucidation of the hemoglobin molecule has revealed the equal accessibility of all four heme sites, disproving the hypothesis.
cross-link: a cross-wise connecting part (as an atom or group) that connects parallel chains in a complex molecule (as a polymer).
cross-word-puzzle: a puzzle in which words are filled into a pattern of numbered squares in answer to correspondingly numbered clues and in such a way that the words read across and down.
CrP: short for creatine phosphate.
cryoprotectant: certain organic chemicals including glycerol and dimethyl sulfoxide (DMSO). Added to the incubating medium, a cryoprotectant shields living cells and even whole embryos from freezing and thawing injuries when they are frozen and preserved for long periods of time in liquid nitrogen and later brought back to active life by thawing.
crystalloid: a collective name introduced by Thomas Graham in 1861 for sugars, salts and other molecules, which diffuse rapidly as solutes in a water solution and which form crystals under suitable conditions.
Cs+: cesium ion. one of the heavier alkali-metal ions.
Cs134: one of the radioactive isotopes of the cesium ion.
cuttlefish: (Sepia) a tenarmed marine cephalopod mollusc differing from the related squids in having a calcified internal shell.
cysteine: a common amino acid found in many protein hydrolysates A cysteine residue in a protein contributes an sulfhydryl group on a short side chain.
cysteinyl SH group: the SH or sulfhydryl group of a cysteine residue in a protein or peptide.
cytoplasm: the protoplasm of a cell outside the nuclear membrane.
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